4-3-050 CRITICAL AREAS REGULATIONS:

A. PURPOSE:

1. General: The purposes of this section are to:

a. Manage development activities to protect environmental quality;

b. Assist or further the implementation of the policies of the Growth Management Act, the State Environmental Policy Act, chapter 43.21C RCW, and the City Comprehensive Plan;

c. Provide City officials with information to evaluate, approve, condition or deny public or private development proposals with regard to critical area impacts;

d. Protect the public life, health, safety, welfare, and property by minimizing and managing the adverse environmental impacts of development within and abutting critical areas; and

e. Protect the public from:

i. Preventable maintenance and replacement of public facilities needed when critical area functioning is impaired;

ii. Unnecessary costs for public emergency rescue and relief operations; and

iii. Potential litigation on improper construction practices occurring in critical areas.

2. Aquifer Protection: The overall purpose of the aquifer protection regulations is to protect aquifers used as potable water supply sources by the City from contamination by hazardous materials. Other specific purposes include:

a. Protect the groundwater resources of the City;

b. Provide a means of regulating specific land uses within aquifer protection areas;

c. Provide a means of establishing safe construction practices for projects built within an aquifer protection area; and

d. Protect the City’s drinking water supply from impacts by facilities that store, handle, treat, use, or produce substances that pose a hazard to groundwater quality.

3. Flood Hazards: It is the purpose of the flood hazard regulations to:

a. Minimize public and private losses due to flood conditions in specific areas; and

b. Minimize expenditure of public money and costly flood control projects; and

c. Minimize the need for rescue and relief efforts associated with flooding and generally undertaken at the expense of the general public; and

d. Minimize damage to public facilities and utilities such as water and gas mains, electric, telephone and sewer lines, streets, and bridges located in areas of special flood hazard; and

e. Help maintain a stable tax base by providing for the sound use and development of areas of special flood hazard so as to minimize future flood blight areas; and

f. Ensure that those who occupy the areas of special flood hazard assume responsibility for their actions.

4. Geologic Hazards: The purposes of the geologic hazard regulations are to:

a. Minimize damage due to landslide, subsidence or erosion through the control of development; and

b. Protect the public against avoidable losses due to maintenance and replacement of public facilities, property damage, subsidy cost of public mitigation of avoidable impacts, and costs for public emergency rescue and relief operations; and

c. Reduce the risks to the City and its citizens from development occurring on unstable slopes; and

d. Control erosion and sediment run-off from development.

5. Habitat Conservation: The primary purpose of habitat conservation regulations is to minimize impacts to critical habitats and to restore and enhance degraded or lower quality habitat in order to:

a. Maintain and promote diversity of species and habitat within the City; and

b. Coordinate habitat protection with the City’s open space system, whenever possible, to maintain and provide habitat connections; and

c. Help maintain air and water quality, and control erosion; and

d. Serve as areas for recreation, education, scientific study, and aesthetic appreciation.

6. Streams and Lakes: The purposes of the stream and lake regulations are to:

a. Protect riparian habitat in order to provide for bank and channel stability, sustained water supply, flood storage, recruitment of woody debris, leaf litter, nutrients, sediment and pollutant filtering, shade, shelter, and other functions that are important to both fish and wildlife; and

b. Prevent the loss of riparian acreage and functions and strive for a net gain over present conditions through restoration where feasible; and

c. Protect aquatic habitat for salmonid species. Other fish/aquatic species are addressed through Habitat Conservation regulations (see subsection A5 of this Section).

7. Wetlands: The purposes of the wetland regulations are to:

a. Ensure that activities in or affecting wetlands do not threaten public safety, cause nuisances, or destroy or degrade natural wetland functions and values; and

b. Preserve, protect and restore wetlands by regulating development within them and around them; and

c. Protect the public from costs associated with repair of downstream properties resulting from erosion and flooding due to the loss of water storage capacity provided by wetlands; and

d. Prevent the loss of wetland acreage and functions and strive for a net gain over present conditions. (Ord. 4851, 8-7-2000; Ord. 5137, 4-25-2005)

B. APPLICABILITY – CRITICAL AREAS DESIGNATIONS/MAPPING:

1. Lands to Which These Regulations Apply: The following critical areas, classified in subsections H1 through M1of this Section, are regulated by this Section:

a. Aquifer protection areas.

b. Areas of special flood hazard.

c. Sensitive slopes, twenty five percent (25%) to forty percent (40%) and protected slopes, forty percent (40%) or greater.

d. Medium, high, and very high landslide hazard areas.

e. High erosion hazards.

f. High seismic hazards.

g. Medium and high coal mine hazards.

h. Volcanic hazard areas.

i. Critical habitats.

j. Streams and Lakes.

i. All applicable requirements of this Section apply to Class 2 to 4 water bodies, as classified in subsection L1 of this Section.

ii. Class 5 water bodies, classified in subsection L1 of this Section, are exempt from all provisions of this Section.

iii. Class 1 water bodies, defined in subsection L1 of this Section, are not subject to this section, and are regulated in RMC 4-3-090, Shoreline Master Program Regulations, and RMC 4-9-197, Shoreline Permits.

k. Wetlands, Categories 1, 2 and 3.

2. Mapping – General:

a. The exact boundary of each critical area depicted on maps referenced herein is approximate and is intended only to provide an indication of the presence of a critical area on a particular site. Additional critical areas may be present on a site. The actual presence of critical areas and the applicability of these regulations shall be based upon the classification criteria for each critical area.

b. The Public Works Department shall provide an annual docket process to update the maps. As of the effective date of the ordinance codified in this section (April 25, 2005), critical area reports prepared for permit applications shall be incorporated into critical area mapping as part of the annual docket process. As a result of studies prepared through the permit application process, where the City requires increased buffers rather than standard buffers, it shall be noted on the map. (Ord. 5450, 3-2-2009)

3. Reports and Submittal Requirements: Study requirements and submittal requirements are required in each regulated critical area as follows:

a. General Submittal Requirements – All Critical Areas: See subsection F of this Section, Submittal Requirements and Fees, and RMC 4-8-120, Submittal Requirements Specific to Application Type.

b. Exempt Activities, Study Requirements: See subsection C4c of this Section, Reports and Mitigation Plans Required.

c. Aquifer Protection Area Permit Submittal Requirements: See subsection H1e of this Section and 4-9-015E.

d. Flood Hazard Data: Flood hazard data is to be applied pursuant to subsection I1b of this Section, Mapping and Documentation.

e. Geologic Hazards Special Studies Required: See subsection J2 of this Section, Special Studies Required.

f. Habitat Conservation Assessment Required: See subsection K2 of this Section, Habitat Assessment Required.

g. Streams and Lakes Studies Required: See subsection L3 of this Section, Studies Required.

h. Wetlands Studies Required: See subsection M3 of this Section, Study Required. (Ord. 4851, 8-7-2000; Ord. 4992, 12-9-2002; Ord. 5137, 4-25-2005)

C. APPLICABILITY – EXEMPT, PROHIBITED AND NONCONFORMING ACTIVITIES:

1. Applicability: Unless determined to be exempt from permitting and standards, all proposed development, fill, and activities in regulated critical areas and their buffers shall comply with the requirements of this Section. Expansion or alteration of existing activities shall also comply with the requirements of this Section. Any person seeking to determine whether a proposed activity or land area is subject to this Section may request in writing a determination from the City. Such a request for determination shall contain the information requirements specified by the Department Administrator.

a. Aquifer Protection Areas – Compliance with Regulations: The following developments, facilities, uses and activities shall comply with the applicable provisions and restrictions of this Section and chapters 4-4, 4-5, 4-6, 4-9, and 5-5 RMC for the APA zone in which the developments, facilities, uses and activities are located, except as preempted by Federal or State law:

i. Development Permits: Development permits shall be reviewed for compliance with the aquifer protection requirements of this Section.

ii. Facilities: Facilities, as defined in RMC 4-11-060, Definitions F, which are existing, new, or to be closed, are subject to this Section as specified below:

(a) Existing Facilities: All owners of facilities which store, handle, treat, use, or produce hazardous materials or have done so in the past must comply with the permit requirements, release reporting requirements, and closure requirements as set forth in this Section;

(b) Existing Facilities – Limitation on Material Increase: In Zone 1 of an APA, no change in operations at a facility shall be allowed that increases the quantities of hazardous materials stored, handled, treated, used, or produced in excess of quantities reported in the initial aquifer protection area operating permit with the following exception: An increase in the quantity of hazardous materials is allowed up to the amount allowed for a new facility in Zone 1 as provided by subsection C8d(i) of this Section, Prohibited Activities – Aquifer Protection Areas, Zone 1;

(c) New Facilities: All proposals for new facilities within any zone of an aquifer protection area must be reviewed for compliance with this Section prior to issuance of any development permits for uses in which hazardous materials are stored, handled, treated, used or produced or which increase the quantity of hazardous materials stored, handled, treated, used, or produced;

(d) Abandonment: No person, persons, corporation or other legal entity shall temporarily or permanently abandon, close, sell, or otherwise transfer a facility in an APA without complying with the requirements of RMC 4-9-015F, Closure Permit, and permit conditions of this Section;

iii. Hazardous Materials – Use, Production, Storage, Treatment, Disposal, or Management: Persons that store, handle, treat, use, or produce a hazardous material as defined by chapter 4-11 RMC, Definitions, shall be subject to the requirements of this Section, and as further specified below:

(a) All applications for development permits for uses in which hazardous materials are stored, handled, treated, used or produced or which increase the quantity of hazardous materials stored, handled, treated, used, or produced at a location in the APA must be reviewed for compliance with this Chapter by the Department prior to approval.

(b) The focus of review for all permits will be on the hazardous materials that will be stored, handled, treated, used, or produced; and the potential for these substances to degrade groundwater quality.

(c) An inventory of hazardous materials on forms provided by the Department shall be submitted to the Department upon application for a development permit.

(d) Where required by the Department, plans and specifications for secondary containment shall be submitted and shall comply with subsection H2d(i) of this Section, Secondary Containment – Zones 1 and 2. Development permits shall not be issued until plans and specifications for secondary containment, if required, have been approved by the Department.

(e) The Generic Hazardous Materials List attached and incorporated as subsection R of this Section is provided for informational purposes.

iv. Application of Pesticides and Nitrates: Persons who apply pesticides and/or fertilizer containing nitrate in the APA, except for homeowners applying only to their own property, shall comply with subsection H3 of this Section, Use of Pesticides and Nitrates – APA Zones 1 and 2.

v. Construction Activities: Persons engaged in construction activities as defined in RMC 4-11-030, Definitions C, shall comply with subsection H7 of this Section, Construction Activity Standards – Zones 1 and 2, and RMC 4-4-030C8, Construction Activity Standards – APA Zones 1 and 2;

vi. Fill Material: Persons placing fill material on sites within the APA shall comply with subsection H8 of this Section, Fill Material Requirements – Zones 1 and 2, and RMC 4-4-060L4, Fill Material;

vii. Fuel Oil Heating Systems: Owners of facilities and structures shall comply with subsection C8d(i)(i) and C8d(ii)(f) of this Section, Prohibited Activities – Aquifer Protection Areas, Zones 1 and 2, relating to conversion of heating systems to fuel oil and installation of new fuel oil heating systems.

viii. Pipelines: Owners of pipelines as defined in RMC 4-11-160 shall comply with subsection H6 of this Section, Pipeline Requirements;

ix. Solid Waste Landfills: Owners of existing solid waste landfills shall comply with subsection H9 of this Section, Regulations for Existing Solid Waste Landfills – Zones 1 and 2;

x. Surface Water Systems: Surface water systems shall meet the requirements of subsection H5 of this Section, Surface Water Requirements, and RMC 4-6-030E, Drainage Plan Requirements and Methods of Analysis;

xi. Unauthorized Release: All persons shall comply with subsection H10 of this Section, Hazardous Materials – Release Restrictions – Zones 1 and 2, and RMC 4-9-015G, Unauthorized Releases;

xii. Wastewater Disposal Systems: Owners of structures that are connected to existing on-site sewage disposal systems and proposed wastewater disposal systems shall comply with subsection H4 of this Section, Wastewater Disposal Requirements, and RMC 4-6-040J, Sanitary Sewer Standards, Additional Requirements that Apply within Zones 1 and 2 of an Aquifer Protection Area.

2. Permit Required:

a. Permit Required – Development or Alteration: Prior to any development or alteration of a property containing a critical area as defined in subsection B of this Section, Applicability – Critical Areas Designations/Mapping, the owner or designee must obtain a development permit, critical area permit, and/or letter of exemption. No separate critical area permit is required for a development proposal which requires development permits or which has received a letter of exemption. If a proposed activity is not exempt and does not otherwise require a development permit, but is subject to this Section, the Department Administrator shall determine whether to grant or deny a separate critical areas permit based upon compliance with applicable standards and regulations of this Section.

b. Aquifer Protection Area – Operating and Closure Permits: Aquifer protection area operating permit and closure permit requirements are contained in RMC 4-9-015, Aquifer Protection Area Permits.

3. Finding of Conformance Required:

a. General: Conformance with these critical area regulations shall be a finding in any approval of a development permit or aquifer protection area permit, and such finding shall be documented in writing in the project file.

b. Aquifer Protection Areas: No changes in land use shall be allowed nor shall permits for development be issued if the Department finds that the proposed land use, activity, or business is likely to impact the long-term, short-term or cumulative quality of the aquifer. The finding shall be based on the present or past activities conducted at the site; hazardous materials that will be stored, handled, treated, used or produced; and the potential for the land use, activity, or business to degrade groundwater quality.

4. Letter of Exemption:

a. Aquifer Protection, Flood Hazards, Geologic Hazards, Habitat Conservation, Streams and Lakes, Wetlands: Except in the case of public emergencies, all exemptions in subsections C5, C6 and C7 of this Section require that a letter of exemption be obtained from the Department Administrator prior to construction or initiation of activities.

b. Applicability of Section Requirements to Exempt Activities: Exempt activities provided with a letter of exemption may intrude into the critical area or required buffer subject to any listed conditions or requirements. Exempt activities do not need to comply with mitigation ratios of subsection M11 of this Section, Wetlands Creation and Restoration, or subsection M12 of this Section, Wetland Enhancement, unless required in exemption criteria.

c. Reports and Mitigation Plans Required: A report for the specific critical area affected, and/or enhancement or mitigation plan shall be required pursuant to subsections H to M of this Section, unless otherwise waived by the Department Administrator.

d. Administrator Findings: In determining whether to issue a letter of exemption for activities listed in subsections C5, C6, and C7 of this Section, the Administrator shall find that:

i. The activity is not prohibited by this or any other chapter of the RMC or State or Federal law or regulation;

ii. The activity will be conducted using best management practices as specified by industry standards or applicable Federal agencies or scientific principles;

iii. Impacts are minimized and, where applicable, disturbed areas are immediately restored, unless the exemption is a wetland below the size thresholds pursuant to subsection C5f(i) of this Section;

iv. Where water body or buffer disturbance has occurred in accordance with an exemption during construction or other activities, revegetation with native vegetation shall be required.

v. If a hazardous material, activity, and/or facility that is exempt pursuant to this Section has a significant or substantial potential to degrade groundwater quality, then the Department Administrator may require compliance with the aquifer protection requirements of this Section otherwise relevant to that hazardous material, activity, and/or facility. Such determinations will be based upon site and/or chemical-specific data.

5. Specific Exemptions – Critical Areas and Buffers: Specific exempt activities are listed in the following table. If an “X” appears in a box, the listed exemption applies in the specified critical area and required buffer. If an “X” does not appear in a box, then the exemption does not apply in the particular critical area or required buffer. Where utilized in the following table the term “restoration” means returning the subject area back at a minimum to its original state following the performance of the exempt activity. Activities taking place in critical areas and their associated buffers and listed in the following table are exempt from the applicable provisions of this Section, provided a letter of exemption has been issued per subsection C4 of this Section, Letter of Exemption. Whether the exempted activities are also exempt from permits will be determined based upon application of chapters 4-8 and 4-9 RMC, or other applicable sections of the Renton Municipal Code.

EXEMPT ACTIVITIES – PERMITTED WITHIN CRITICAL AREAS AND ASSOCIATED BUFFERS
EXEMPT ACTIVITY	Aquifer Protection Area	Flood Hazard Area	Geologic Hazard Area	Habitat Conservation Area	Streams and Lakes: Class 2 to 4	Wetlands
a. Conservation, Enhancement, Education and Related Activities:
i. Natural Resource/Habitat Conservation or Preservation: Conservation or preservation of soil, water, vegetation, fish and other wildlife.	X1	X	X	X	X	X
ii. Enhancement activities as defined in chapter 4-11 RMC.		X	X	X	X	X
iii. Approved Restoration/Mitigation: Any critical area and/or buffer restoration or other mitigation activities which have been approved by the City.	X1	X	X	X	X	X
b. Research and Site Investigation:
i. Education and Research: Nondestructive education and research.	X1	X	X	X	X	X
ii. Site Investigative Work: Site investigative work necessary for land use application submittals such as surveys, soil logs, percolation tests and other related activities. Investigative work shall not disturb any more than five percent (5%) of the critical area and required buffer. In every case, impacts shall be minimized and disturbed areas shall be immediately restored at a 1:1 ratio.	X1	X	X	X	X	X
c. Agricultural, Harvesting, Vegetation Management:
i. Harvesting Wild Foods: The harvesting of wild foods in a manner that is not injurious to natural reproduction of such foods and provided the harvesting does not require tilling of soil, planting of crops or alteration of the critical area.	X1	X	X	X	X	X
c. Agricultural, Harvesting, Vegetation Management: (Continued)
ii. Existing/Ongoing Agricultural Activities: Existing and ongoing agricultural activities including farming, horticulture, aquaculture and/or maintenance of existing irrigation systems. Activities on areas lying fallow as part of a conventional rotational cycle are part of an ongoing operation; provided, that the agricultural activity must have been conducted within the last five (5) years. Activities that bring a critical area into agricultural use are not part of an ongoing operation. Maintenance of existing legally installed irrigation, ditch and pipe systems is allowed; new or expanded irrigation, ditch, outfall or other systems are not exempt. If it is necessary to reduce the impacts of agricultural practices to critical areas, a farm management plan may be required based on the King County Conservation District’s Farm Conservation and Practice Standards, or other best management practices. (Ord. 5676, 12-3-2012)		X	X	X	X	X
iii. Dead or Diseased Trees: Removal of dead, terminally diseased, damaged, or dangerous ground cover or hazard trees which have been certified as such by a forester, registered landscape architect, or certified arborist, selection of which to be approved by the City based on the type of information required, or the City prior to their removal.	X1	X	X	X	X: Limited to cutting of hazard trees; such hazard trees shall be retained as large woody debris in the stream/buffer corridor, where feasible.	X: Tree cutting of hazard trees or other woody vegetation accomplished such that trees are retained in the wetland and buffer where feasible.
d. Surface Water:
i. New Surface Water Discharges: New surface water discharges to wetland Categories 1, 2 and 3, or buffers of Categories 1, 2 and 3, and to streams or lakes from detention facilities, presettlement ponds or other surface water management structures; provided, the discharge meets the requirements of the Storm and Surface Water Drainage Regulations (RMC 4-6-030); will not result in significant adverse changes in the water temperature or chemical characteristics of the wetland or stream/lake water sources; and there is no increase in the existing rate of flow unless it can be demonstrated that the change in hydrologic regime would result in equal or improved wetland or stream/lake functions and values. Where differences exist between these regulations and RMC 4-6-030, these regulations will take precedence.				X	X	X
ii. New or Modified Regional Stormwater Facilities: Regional stormwater management facilities to be operated and maintained under the direction of the City Surface Water Utility that are proposed and designed consistent with the Washington State Department of Ecology Wetlands and Stormwater Management Guidelines or meeting equivalent objectives. (Ord. 5526, 2-1-2010)						X
iii. Flood Hazard Reduction: Implementation of public flood hazard reduction and public surface water projects, where habitat enhancement and restoration at a 1:1 ratio are provided, and appropriate Federal and/or State authorization has been received.		X			X
iv. Storm Drainage Piping: Installation of new storm drainage lines in any geologic hazard area when a geotechnical report clearly demonstrates that the installation would comply with the criteria listed in RMC 4-3-050J2b and that the installation would be consistent with each of the purposes of the geologic hazard regulations listed in RMC 4-3-050A4. Also, to qualify for the exemption, the report must propose appropriate mitigation for any potential impacts identified in the report.			X
e. Roads, Parks, Public and Private Utilities:
i. Relocation of Existing Utilities out of Critical Area and Buffer: Relocation out of critical areas and required buffers of natural gas, cable, communication, telephone and electric facilities, lines, pipes, mains, equipment and appurtenances (not including substations), with an associated voltage of fifty five thousand (55,000) volts or less, only when required by a local governmental agency, and with the approval of the City. Disturbed areas shall be restored.	X1	X	X	X	X	X
1If a hazardous material, activity, and/or facility that is exempt pursuant to this Section has a significant or substantial potential to degrade groundwater quality, then the Department Administrator may require compliance with the aquifer protection requirements of this Section otherwise relevant to that hazardous material activity and/or facility.

 

EXEMPT ACTIVITIES – PERMITTED WITHIN CRITICAL AREAS AND ASSOCIATED BUFFERS
EXEMPT ACTIVITY	Aquifer Protection Area	Flood Hazard Area	Geologic Hazard Area	Habitat Conservation Area	Streams and Lakes: Class 2 to 4	Wetlands
e. Roads, Parks, Public and Private Utilities: (Continued)
ii. Existing Parks, Trails, Roads, Facilities, and Utilities – Maintenance, Operation, Repair: Normal and routine maintenance, operation and repair of existing parks and trails, streets, roads, rights-of-way and associated appurtenances, facilities and utilities where no alteration or additional fill materials will be placed other than the minimum alteration and/or fill needed to restore those facilities to meet established safety standards. The use of heavy construction equipment shall be limited to utilities and public agencies that require this type of equipment for normal and routine maintenance and repair of existing utility structures and rights-of-way. In every case, critical area and required buffer impacts shall be minimized and disturbed areas shall be restored during and immediately after the use of construction equipment.			X	X	X	X
iii. Utilities, Traffic Control, Walkways, Bikeways Within Existing, Improved Right-of-Way or Easements: Within existing and improved public road rights-of-way or easements, installation, construction, replacement, operation, overbuilding or alteration of all natural gas, cable, communication, telephone and electric facilities, lines, pipes, mains, equipment or appurtenances, traffic control devices, illumination, walkways and bikeways. If activities exceed the existing improved area or the public right-of-way, this exemption does not apply. Where applicable, restoration of disturbed areas shall be completed.			X	X	X	X
e. Roads, Parks, Public and Private Utilities: (Continued)
iv. Modification of Existing Utilities and Streets by Ten Percent (10%) or Less: Overbuilding (enlargement beyond existing project needs) or replacement of existing utility systems and replacement and/or rehabilitation of existing streets, provided: (1) The work does not increase the footprint of the structure, line or street by more than ten percent (10%) within the critical area and/or buffer areas, and occurs in the existing right-of-way boundary or easement boundary. (2) Restoration shall be conducted where feasible. Compensation for impacts to buffers shall include enhancement of the remaining buffer area along the impacted area where there is enhancement opportunity. (3) The Administrator determines that, based on best judgment, a person would not: (a) be able to meaningfully measure, detect, or evaluate insignificant effects; or (b) expect discountable effects to occur. (4) This exemption allows for 10% maximum expansion total, life of the project. After the 10% expansion cap is reached, future improvements are subject to all applicable provisions of this Section.			X	X: Exemption is not allowed in Category 1 wetlands.		X: Exemption is not allowed in Category 1 wetlands.
v. Vegetation Management/Essential Tree Removal for Public or Private Utilities, Roads, and Public Parks: Maintenance activities, including routine vegetation management and essential tree removal, and removal of non-native invasive vegetation or weeds listed by the King County Noxious Weed Board or other government agency, for public and private utilities, road rights-of-way and easements, and parks.		X	X	X	X: Trees shall be retained as large woody debris in the stream/buffer corridor, where feasible.	X: Tree cutting and vegetation management accomplished such that trees are retained in the wetland and buffer where feasible.
f. Wetland Disturbance, Modification and Removal:
i. Any Activity in Small Category 3 Wetlands: Any activity affecting hydrologically isolated Category 3 wetland no greater than two thousand two hundred (2,200) square feet when consistent with all of the following criteria: (1) Standing water is not present in sufficient amounts, i.e., approximately twelve inches (12") to eighteen inches (18") in depth from approximately December through May, to support breeding amphibians; (2) Species listed by Federal or State government as endangered or threatened, or the presence of essential habitat for those species, are not present; (3) Some form of mitigation is provided for hydrologic and water quality functions, for example, stormwater treatment or landscaping or other mitigation; and (4) A wetland assessment is prepared by a qualified professional demonstrating the criteria of the exemption are met. The wetland assessment shall be subject to independent secondary review at the expense of the applicant consistent with subsection F7 of this Section.						X
ii. Temporary Wetland Impacts: Temporary disturbances of a wetland due to construction activities that do not include permanent filling may be permitted; provided, that there are no permanent adverse impacts to the critical area or required buffer, and areas temporarily disturbed are restored at a 1:1 ratio. Category 1 wetlands and Category 2 forested wetlands shall be enhanced at a 2:1 ratio in addition to being restored. For habitat conservation areas, this exemption applies only to Category 1 wetlands.				X		X
g. Maintenance and Construction – Existing Uses and Facilities:
i. Remodeling, Replacing, Removing Existing Structures, Facilities, and Improvements: Remodeling, restoring, replacing or removing structures, facilities and other improvements in existence on the date this section becomes effective and that do not meet the setback or buffer requirements of this section provided the work complies with the criteria in RMC 4-10-090.			X	X	X	X
g. Maintenance and Construction – Existing Uses and Facilities: (Continued)
ii. Maintenance and Repair – Any Existing Public or Private Use: Normal and routine maintenance and repair of any existing public or private uses and facilities where no alteration of the critical area and required buffer or additional fill materials will be placed. The use of heavy construction equipment shall be limited to utilities and public agencies that require this type of equipment for normal and routine maintenance and repair of existing utility or public structures and rights-of-way. In every case, critical area and required buffer impacts shall be minimized and disturbed areas shall be restored during and immediately after the use of construction equipment.			X	X	X	X
iii. Modification of an Existing Single Family Residence: Construction activity connected with an existing single family residence and/or garage; provided, that the work does not increase the footprint of the structure lying within the critical area or buffer; and provided, that no portion of the new work occurs closer to the critical area or required buffers than the existing structure unless the structure or addition can meet required buffers. Existing or rebuilt accessory structures associated with single family lots such as fences, gazebos, storage sheds, and play houses are exempt from this Section. New accessory structures may be allowed when associated with single family lots such as fences, gazebos, storage sheds, play houses and when built on and located in a previously legally altered area.			X	X	X	X
iv. Existing Activities: Existing activities which have not been changed, expanded or altered, provided they comply with the applicable requirements of chapter 4-10 RMC.		X	X	X	X	X
h. Emergency Activities:
i. Emergency Activities: Emergency activities are those which are undertaken to correct emergencies that threaten the public health, safety and welfare pursuant to the criteria in subsection C9b of this Section. An emergency means that an action must be undertaken immediately or within a time frame too short to allow full compliance with this Section, to avoid an immediate threat to public health or safety, to prevent an imminent danger to public or private property, or to prevent an imminent threat of serious environmental degradation.	X1	X	X	X	X	X
ii. Emergency Tree/Ground Cover Cutting or Removal by Agency or Utility: Removal of trees and/or ground cover by any City department or agency and/or public or private utility in emergency situations involving immediate danger to life or property, substantial fire hazards, or interruption of services provided by a utility.	X1	X	X	X	X: Downed hazard trees shall be retained as large woody debris in the stream/buffer.	X: Tree cutting and vegetation management accomplished such that trees are retained in the wetland and buffer where feasible.
iii. Emergency Activities in Aquifer Protection Area: Public interest emergency use, storage, and handling of hazardous materials by governmental organizations.	X1
i. Hazardous Materials:
i. Federal or State Pre-emption: Cleanups, monitoring and/or studies undertaken under supervision of the Washington Department of Ecology or the U.S. Environmental Protection Agency.	X1
ii. Use of Materials with No Risk: Use, storage, and handling of specific hazardous materials that do not present a risk to the aquifer as determined and listed by the Department.	X1
1If a hazardous material, activity, and/or facility that is exempt pursuant to this Section has a significant or substantial potential to degrade groundwater quality, then the Department Administrator may require compliance with the aquifer protection requirements of this Section otherwise relevant to that hazardous material activity and/or facility.

6. Limited Exemptions: Activities that are exempt from some, but not all provisions of this Section are listed in the following table. If an “X” appears in a box, the listed exemption applies in the specified critical area and required buffer. If an “X” does not appear in a box, then the exemption does not apply in the particular critical area or required buffer. Whether the exempted activities are also exempt from permits will be determined based upon application of chapters 4-8 and 4-9 RMC, or other applicable sections of the Renton Municipal Code.

 

LIMITED EXEMPTIONS – WITHIN CRITICAL AREAS AND ASSOCIATED BUFFERS
EXEMPT ACTIVITY	Aquifer Protection Area	Flood Hazard Area	Geologic Hazard Area	Habitat Conservation Area	Streams and Lakes: Class 2 to 4	Wetlands
a. Hazardous Materials:
i. Materials for Sale in Original Small Containers: Hazardous materials offered for sale in their original containers of five (5) gallons or less shall be exempt from requirements in subsections H2d(i) through (vi) of this Section and the requirements pertaining to removal of existing facilities in subsection H2a(i).	X1
ii. Activities Exempt from Specified Aquifer Protection Area Requirements: The following are exempt from requirements in subsections H2d(i) through (vi) of this Section, the requirements pertaining to review of proposed facilities in subsection C8d, Prohibited Changes in Land Use and Types of New Facilities – Aquifer Protection Areas, and the requirements pertaining to removal of existing facilities in subsection H2a(i).	X1
(1) Hazardous materials use, storage, and handling in de minimis amounts (aggregate quantities totaling twenty (20) gallons or less at the facility or construction site). Weights of solid hazardous materials will be converted to volumes for purposes of determining whether de minimis amounts are exceeded. Ten (10) pounds shall be considered equal to one gallon.	X1
(2) Noncommercial residential use, storage, and handling of hazardous materials; provided, that no home occupation business (as defined by chapter 4-11 RMC) that uses, stores, or handles more than twenty (20) gallons of hazardous material is operated on the premises.	X1
(3) Hazardous materials in fuel tanks and fluid reservoirs attached to a private or commercial motor vehicle and used directly in the operation of that vehicle.	X1
(4) Fuel oil used in existing heating systems.	X1
(5) Hazardous materials used, stored, and handled by the City of Renton in water treatment processes and water system operations.	X1
a. Hazardous Materials: (Continued)
(6) Fueling of equipment not licensed for street use; provided, that such fueling activities are conducted in a containment area that is designed and maintained to prevent hazardous materials from coming into contact with soil, surface water, or groundwater except for refueling associated with construction activity regulated by subsection H7 of this Section, Construction Activity Standards – Zones 1 and 2.	X1
(7) Hazardous materials contained in properly operating sealed units (transformers, refrigeration units, etc.) that are not opened as part of routine use.	X1
(8) Hazardous materials in fuel tanks and fluid reservoirs attached to private or commercial equipment and used directly in the operation of that equipment.	X1
(9) Hazardous materials in aerosol cans.	X1
(10) Hazardous materials at multi-family dwellings, hotels, motels, retirement homes, convalescent centers/nursing homes, mobile or manufactured home parks, group homes, and daycare family homes or centers when used by owners and/or operators of such facilities for on-site operation and maintenance purposes.	X1
(11) Hazardous materials used for janitorial purposes at the facility where the products are stored.	X1
(12) Hazardous materials used for personal care by workers or occupants of the facility at which the products are stored including but not limited to soaps, hair treatments, grooming aids, health aids, and medicines.	X1
iii. Uses, Facilities, and Activities in Zone 1 Modified Aquifer Protection Area Exempt from Specified Aquifer Protection Area Requirements: Facilities located in the Zone 1 Modified Aquifer Protection Area in Figure 4-3-050Q1 are exempt from the following:	X1
(1) Removal requirements in subsection H2a(i) of this Section except that the storage, handling, use, treatment, and production of tetrachloroethylene (e.g., dry-cleaning fluid) shall continue to be prohibited;	X1
(2) Additional facility requirements in subsection H2d(vi) of this Section;	X1
a. Hazardous Materials: (Continued)
(3) Wastewater requirements in RMC 4-6-040J1a but shall be subject to Zone 2 requirements in RMC 4-6-040J2;	X1
(4) The prohibition of septic systems contained in subsection C8d(i)(f) of this Section; and	X1
(5) Surface water management requirements of RMC 4-6-030E except that Zone 2 requirements contained in RMC 4-6-030E shall apply.	X1
1If a hazardous material, activity, and/or facility that is exempt pursuant to this Section has a significant or substantial potential to degrade groundwater quality, then the Department Administrator may require compliance with the aquifer protection requirements of this Section otherwise relevant to that hazardous material activity and/or facility.

7. Exemptions in Buffers: The activities listed in the following table are allowed within critical area buffers, and are exempt from the applicable provisions of this Section, provided a letter of exemption has been issued per subsection C4 of this Section, Letter of Exemption. If an “X” appears in a box, the listed exemption applies in the specified buffer. If an “X” does not appear in a box, then the exemption does not apply in the required buffer. Whether the exempted activities are also exempt from permits will be determined based upon application of chapters 4-8 and 4-9 RMC, or other applicable sections of the Renton Municipal Code.

 

EXEMPTIONS WITHIN CRITICAL AREA BUFFERS
EXEMPT ACTIVITY	Aquifer Protection Area	Flood Hazard Area	Geologic Hazard Area	Habitat Conservation Area	Streams and Lakes: Class 2 to 4	Wetlands
a. Activities in Critical Area Buffers:
i. Trails and Open Space: Walkways and trails, and associated open space in critical area buffers located on public property, or where easements or agreements have been granted for such purposes on private property. All of the following criteria shall be met.			X	X	X	X
(1) The trail, walkway, and associated open space shall be consistent with the Comprehensive Parks, Recreation, and Open Space Master Plan. The City may allow private trails as part of the approval of a site plan, subdivision or other land use permit approvals.
(2) Trails and walkways shall be located in the outer twenty-five percent (25%) of the buffer, i.e., the portion of the buffer that is farther away from the critical area. Exceptions to this requirement may be made for:
• Trail segments connecting to existing trails where an alternate alignment is not practical.
• Public access points to water bodies spaced periodically along the trail.
(3) Enhancement of the buffer area is required where trails are located in the buffer. Where enhancement of the buffer area abutting a trail is not feasible due to existing high quality vegetation, additional buffer area or other mitigation may be required. (Ord. 5676, 12-3-2012)
(4) Trail widths shall be a maximum width of twelve (12) feet. Trails shall be constructed of permeable materials. Impervious materials may be allowed if pavement is required for handicapped or emergency access, or safety, or is a designated nonmotorized transportation route or makes a connection to an already dedicated trail, or reduces potential for other environmental impacts.
ii. Stormwater Treatment and Flow Control Facilities in Buffer: Stormwater management facilities shall not be built within a critical area buffer except as allowed in Reference 5, Wetlands Protection Guidelines of the City’s Surface Water Design Manual and shall require buffer enhancement or buffer averaging when they are sited in areas of forest vegetation, provided the standard buffer zone area associated with the critical area classification is retained pursuant to subsection L or M6c of this Section, and is sited to reduce impacts between the critical area and surrounding activities. (Ord. 5526, 2-1-2010)						X
iii. Stormwater Conveyance in Buffer: Necessary conveyance systems including stormwater dispersion outfall systems designed to minimize impacts to the buffer and critical area, where the site topography requires their location within the buffer to allow hydraulic function, provided the standard buffer zone area associated with the critical area classification is retained pursuant to subsection L or M6c of this Section, and is sited to reduce impacts between the critical area and surrounding activities. (Ord. 5526, 2-1-2010)				X	X	X

8. Prohibited Activities: Prohibited activities are identified below for each critical area governed by this Section.

a. General – All Critical Areas: No action shall be taken by any person, company, agency, or applicant which results in any alteration of a critical area except as consistent with the purpose, objectives, and requirements of this Section.

b. Prohibited Activities – Floodways: Encroachments, including fill, new construction, substantial improvements, and construction or reconstruction of residential structures is prohibited within designated floodways, unless it meets the provisions of subsection I4 of this Section, Additional Restrictions within Floodways.

c. Prohibited Activities – Streams/Lakes and Wetlands: Grazing of animals is not allowed within a stream, lake, wetland or their associated buffers.

d. Prohibited Changes in Land Use and Types of New Facilities– Aquifer Protection Areas.

i. Zone 1:

(a) Changes in land use and types of new facilities in which any of the following will be on the premises:

(1) More than five hundred (500) gallons of hazardous material;

(2) More than one hundred fifty (150) gallons of hazardous material in containers that are opened and handled;

(3) Containers exceeding five (5) gallons in size; or

(4) Tetrachloroethylene (e.g., dry-cleaning fluid).

(b) Surface impoundments (as defined in chapters 173-303 and 173-304 WAC);

(c) Hazardous waste treatment, storage, and disposal facilities;

(d) All types of landfills, including solid waste landfills;

(e) Transfer stations;

(f) Septic systems;

(g) Recycling facilities that handle hazardous materials;

(h) Underground hazardous material storage and/or distribution facilities;

(i) New heating systems using fuel oil except for commercial uses when the source of fuel oil is an existing above-ground waste oil storage tank; and

(j) Petroleum product pipelines.

ii. Zone 2:

(a) Surface impoundments (as defined in chapters 173-303 and 173-304 WAC);

(b) Recycling facilities that handle hazardous materials;

(c) Hazardous waste treatment, storage, and disposal facilities;

(d) Solid waste landfills;

(e) Transfer stations;

(f) New heating systems using fuel oil stored in underground storage tanks; and

(g) Petroleum product pipelines.

9. Temporary Emergency Exemption Procedure:

a. Temporary Emergency Exemption Purpose: Temporary emergency exemptions shall be used only in extreme cases and not to justify poor planning by an agency or applicant.

b. Temporary Emergency Exemption Review Authority and Decision Criteria: Issuance of an emergency permit by the City does not preclude the necessity to obtain necessary approvals from appropriate Federal and State authorities. Notwithstanding the provisions of this section or any other City laws to the contrary, the Department Administrator may issue a temporary emergency exemption letter if the action meets the following requirements:

i. An unacceptable threat to life or severe loss of property will occur if an emergency permit is not granted;

ii. The anticipated threat or loss may occur before a permit can be issued or modified under the procedures otherwise required by this Section and other applicable laws;

iii. Any emergency exemption letter granted shall incorporate, to the greatest extent practicable and feasible but not inconsistent with the emergency situation, the standards and criteria required for nonemergency activities under this Section.

c. Temporary Emergency Exemption Letter Process and Timing: The emergency exemption shall be consistent with the following procedural and time requirements:

i. Time Limits: The emergency shall be limited in duration to the time required to complete the authorized emergency activity; provided, that no emergency permit be granted for a period exceeding ninety (90) days except as specified in subsection C9c(ii) of this Section.

ii. Restoration Required: Require, within the ninety (90) day period, the restoration of any critical area altered as a result of the emergency activity, except that if more than ninety (90) days from the issuance of the emergency permit is required to complete restoration, the emergency permit may be extended to complete this restoration. For the purposes of this paragraph, restoration means returning the affected area to its state prior to the performance of the emergency activity.

iii. Public Notice Required: Notice of the issuance of the emergency permit and request for public comments shall be posted at the affected site(s) and City Hall no later than ten (10) days after the issuance of the emergency permit. If significant comments are received, the City may reconsider the permit.

iv. Expiration of Exemption Authorization: The emergency exemption authorization may be terminated at any time without process upon a determination by the Department Administrator that the action was not or is no longer necessary to protect human health or the environment.

10. Nonconforming Activities or Structures: Regulated activities legally in existence prior to the passage of this Section, but which are not in conformity with the provisions of this Section are subject to the provisions of RMC 4-10-090, Critical Areas Regulations – Nonconforming Activities and Structures. (Ord. 4851, 8-7-2000; Ord. 4992, 12-9-2002; Ord. 5137, 4-25-2005; Ord. 5308, 9-24-2007)

D. ADMINISTRATION AND INTERPRETATION:

1. General Provisions – All Critical Areas:

a. Duties of Administrator: The Community and Economic Development Administrator shall have the power and authority to enforce the provisions of this Section. For such purposes the Administrator shall have the power of a law enforcement officer. (Ord. 5450, 3-2-2009)

b. Interpretation: The Administrator shall have the power to render interpretations of this Section and to adopt and enforce rules and regulations supplemental to this Section as he/she may deem necessary in order to clarify the application of the provisions of this Code. Such interpretations, rules and regulations shall be in conformity with the intent and purpose of this Section.

c. Compliance: Unless specifically exempted by this Section, the City shall not grant any approval or permit any regulated activity in a critical area or associated buffer prior to fulfilling the requirements of this Section.

2. Aquifer Protection:

a. Inspections Authorized: The Administrator or his/her designee shall have the right to conduct inspections of facilities at all reasonable times to determine compliance with this Section.

i. Annual Inspections: All permitted facilities in an APA will be subject to a minimum of one inspection per year by a Department inspector.

ii. Monthly Inspections: All permitted facilities in Zone 1 of the aquifer protection area will be subject to monthly inspections to determine compliance with the provisions of the Section.

b. Potential to Degrade Groundwater – Zone 2:

i. Potential for Impacts Equal to Facility in Zone 1: If the Administrator determines that an existing or proposed facility located in Zone 2 of an APA has a potential to degrade groundwater quality which equals or exceeds that of a permitted facility in Zone 1, then the Administrator may require that facility to fully comply with requirements for Zone 1 contained in subsections C1ai, Development Permits, C8di, Zone 1, H2, Facilities, H4, Wastewater Disposal Requirements – Zones 1 and 2, and H6, Pipeline Requirements.

ii. Criteria: Criteria used to make the determination in subsection D2b(i) of this Section, Potential for Impacts Equal to Facility in Zone 1, shall include but not be limited to the present and past activities conducted at the facility; types and quantities of hazardous materials stored, handled, treated, used or produced; the potential for the activities or hazardous materials to degrade groundwater quality; history of spills at the site, and presence of contamination on site.

3. Flood Hazards:

a. Duties and Responsibilities of the Administrator: The duties of the Administrator shall include, but not be limited to:

i. Review all development permits to determine that the permit requirements of this Section have been satisfied; and

ii. Review all development permits to determine that all necessary permits have been obtained from those Federal, State or local governmental agencies from which prior approval is required; and

iii. Review all development permits to determine if the proposed development is located in the floodway. If located in the floodway, assure that the encroachment provisions of subsection I4 of this Section, Additional Restrictions within Floodways, are met; and

iv. Obtain, review, and reasonably utilize any base flood elevation and floodway data available from a Federal, State or other source, when base flood elevation data has not been provided in accordance with subsection I1bi of this Section in order to administer subsection I3, Specific Standards, and subsection I4, Additional Restrictions Within Floodways.

b. Information to Be Obtained and Maintained: The Administrator shall obtain and maintain the following information:

i. Record Required: Where base flood elevation data is provided through the flood insurance study or required as in subsection D3a(iv) of this Section, use of other base flood data, the applicant shall obtain and record the actual elevation (in relation to mean sea level) of the lowest floor (including basement) of all new or substantially improved structures, and whether or not the structure contains a basement.

ii. Elevations and Certificates: For all new or substantially improved floodproofed structures:

(a) The applicant shall verify and record the actual elevation (in relation to mean sea level); and

(b) The Administrator shall maintain the floodproofing certifications required in RMC 4-8-120D6, Flood Hazard Data; and

(c) Flood elevation certificates shall be submitted by an applicant to the Development Services Division prior to the building’s finished floor construction. Finished floor elevation should be verified by a preconstruction elevation certificate at the time of construction of a substantial structural element of the finished floor (i.e., foundation form for the concrete floor). An as-built elevation certificate will be provided prior to issuance of final occupancy, and the certificates shall be maintained by the Administrator.

iii. Public Records: The Administrator shall maintain for public inspection all records pertaining to the provisions of the flood hazard regulations (e.g., elevation certificates, notification of alteration/relocation of watercourses, flood hazard regulation variances).

c. Alteration of Watercourses: The Administrator shall:

i. Notice Required: Notify abutting communities and the State of Washington Department of Ecology prior to any alteration or relocation of a watercourse, and submit evidence of such notification to the Federal Insurance Administration.

ii. Maintenance: Require that maintenance is provided within the altered or relocated portion of said watercourse so that the flood-carrying capacity is not diminished. The City may require covenants, or other mechanisms to ensure maintenance.

d. Interpretation of FIRM Boundaries: The Administrator shall make interpretations where needed, as to exact location of the boundaries of the areas of special flood hazard (for example, where there appears to be a conflict between a mapped boundary and actual field conditions). The person contesting the location of the boundary shall be given a reasonable opportunity to appeal the interpretation as provided in RMC 4-8-070G, Hearing Examiner, and RMC 4-8-110, Appeals).

e. Record Required: The Administrator shall maintain the records of all appeal actions and report any variances to the Federal Insurance Administration upon request.

4. Review Authority:

a. Review Authority – General: The Administrator is authorized to make the following administrative allowances and determinations:

i. Issue a critical areas permit for proposals not otherwise requiring a development permit per subsection C3 of this Section, Finding of Conformance Required.

ii. Issue written letters of exemption pursuant to subsection C4 of this Section.

iii. Allow temporary emergency exemptions per subsection C7 of this Section.

iv. Interpret critical areas regulations per subsection D1b of this Section.

v. Approve the use of alternates in accordance with subsection N1 of this Section and RMC 4-9-250E.

vi. Waive report content or submittal requirements per subsection F6 of this Section.

vii. Grant administrative variances to those specified code sections listed in RMC 4-9-250B and per subsection N of this Section.

viii. Require tests for proof of compliance.

ix. Grant modifications per subsection N of this Section.

b. Review Authority – Geologic Hazards, Habitat Conservation, Streams and Lakes, and Wetlands: The Administrator is authorized to make the following administrative allowances and determinations:

i. Geologic Hazards.

(a) Waive independent review of geotechnical reports per subsection F7 of this Section.

(b) Increase or decrease required buffer for very high landslide hazard areas per subsection J7b of this Section.

(c) Waive coal mine hazard reports per subsection J8 of this Section.

(d) Grant a modification for created slopes per subsection N2 of this Section.

ii. Habitat Conservation: Waive habitat/wildlife assessment reports per subsection K2 of this Section.

iii. Streams and Lakes:

(a) Waive water body study requirement per subsection L3 of this Section.

(b) Approve proposals for buffer width reductions in accordance with the review criteria stated in subsection L5c of this Section.

(c) Approve proposals for buffer width averaging pursuant to the standards and criteria stated in subsection L5d of this Section.

iv. Wetlands:

(a) Waive wetland assessment requirement per subsection M3b of this Section.

(b) Determine whether wetlands are unregulated per subsections M1a and M1b of this Section.

(c) Extend the valid period of a wetland delineation pursuant to subsection M4d of this Section.

(d) Approve proposals for buffer width reductions of up to twenty five percent (25%) in accordance with the review criteria stated in subsection M6e of this Section.

(e) Approve proposals for buffer width averaging pursuant to the standards and criteria stated in subsection M6f of this Section.

(f) Authorize other category level for created or restored wetlands per subsection M11c of this Section.

(g) Waive requirements of this Section upon determination that all impacts on wetlands would be mitigated as part of an approved area-wide wetlands plan that, when taken as a whole over an approved schedule or staging of plan implementation, will meet or exceed the requirements of this section (see subsection M9 of this Section).

c. Review Authority – Aquifer Protection Areas: The Administrator is authorized to make the following administrative allowances and determinations:

i. Issue operating and closure permits.

ii. Determine pipeline requirements per subsection H6a(iii) and H6b of this Section.

iii. Determine if Zone 1 requirements should apply in Zone 2 of an APA per subsection D2b, Potential to Degrade Groundwater – Zone 2, and C8d(ii), Zone 2.

5. Authority to Approve, Condition, or Deny – General: Based upon site specific review and analysis, a proposal may be approved, conditioned, or denied.

6. Relationship to Other Agencies and Regulations: Compliance with the provisions of this Title does not constitute compliance with other federal, state, and/or other local agency regulations and permit requirements that may be required. The applicant is responsible for complying with these requirements, apart from the process established in this Title. (Ord. 4851, 8-7-2000; Ord. 5137, 4-25-2005; Ord. 5676, 12-3-2012)

E. GENERAL PERFORMANCE STANDARDS, AND ALLOWED ALTERATIONS:

1. Performance Standards: The performance standards for each critical area are specified in subsections G to M of this Section. The standards are minimum standards.

2. Protection of Critical Areas: Critical areas and any associated buffers shall be avoided, and undisturbed, unless alterations are permitted in accordance with the requirements of this Section.

3. Allowed Alterations: Critical areas may be altered by authorized exempt activities, alterations specifically allowed in subsections H to M of this Section and subject to listed criteria, or through approval of modifications or variances.

4. Native Growth Protection Areas:

a. Applicability:

i. Required: A native growth protection area shall be instituted when required by subsections H to M of this Section in order to protect a critical area from any proposed development for a non-exempt activity as follows:

(a) Protected slopes per subsection J5e of this Section.

(b) Very high landslide hazard areas per subsection J7c of this Section.

(c) Class 2 to 4 streams or lakes and their associated buffers per subsection L7 of this Section.

(d) Wetlands and their associated buffers per subsection M7 of this Section.

ii. Applied with Discretion: Native growth protection areas may be required for very high landslide hazard area buffers, or for critical habitats and their buffers pursuant to subsections J7 and K4 of this Section.

iii. Application as Condition of Approval When Otherwise Not Required: Where subsections H to M do not require a native growth protection area, the proposal may be conditioned to provide for native growth protection areas. (Ord. 5676, 12-3-2012)

b. Standards:

i. Trees and ground cover shall be retained in designated native growth protection areas.

ii. Activities allowed in a native growth protection areas shall be consistent with applicable critical area regulations.

iii. The City may require enhancement of native growth protection areas to improve functions and values, reduce erosion or landslide potential, or to meet another identified purpose of this section or of critical area regulations.

c. Method of Creation: Native growth protection areas shall be established by one of the following methods, in order of preference:

i. Conservation Easement: The permit holder shall, subject to the City’s approval, convey to the City or other public or nonprofit entity specified by the City, a recorded easement for the protection of the critical area and/or its buffer.

ii. Protective Easement: The permit holder shall establish and record a permanent and irrevocable easement on the property title of a parcel or tract of land containing a critical area and/or its buffer created as a condition of a permit. Such protective easement shall be held by the current and future property owner, shall run with the land, and shall prohibit development, alteration, or disturbance within the easement except for purposes of habitat enhancement as part of an enhancement project which has received prior written approval from the City, and from any other agency with jurisdiction over such activity.

iii. Tract and Deed Restriction: The permit holder shall establish and record a permanent and irrevocable deed restriction on the property title of any critical area management tract or tracts created as a condition of a permit. Such deed restriction(s) shall prohibit development, alteration, or disturbance within the tract except for purposes of habitat enhancement as part of an enhancement project which has received prior written approval from the City, and from any other agency with jurisdiction over such activity. A covenant shall be placed on the tract restricting its separate sale. Each abutting lot owner or the homeowners’ association shall have an undivided interest in the tract.

d. Marking During Construction: The location of the outer extent of the critical area buffer and areas not to be disturbed pursuant to an approved permit shall be marked with barriers easily visible in the field to prevent unnecessary disturbance by individuals and equipment during the development or construction of the approved activity.

e. Fencing: The City shall require permanent fencing of the native growth protection area containing critical area and buffers when there is a substantial likelihood of human or domesticated animal intrusion, and such fencing will not adversely impact habitat connectivity.

f. Signage Required: The common boundary between a native growth protection area and the abutting land must be permanently identified. This identification shall include permanent wood or metal signs on treated or metal posts. Sign locations and size specifications shall be approved by the City. Suggested wording is as follows: “Protection of this natural area is in your care. Alteration or disturbance is prohibited by law.”

g. Responsibility for Maintenance: Responsibility for maintaining the native growth protection easements or tracts shall be held by a homeowners’ association, abutting lot owners, the permit applicant or designee, or other appropriate entity, as approved by the City.

h. Maintenance Covenant and Note Required: The following note shall appear on the face of all plats, short plats, PUDs, or other approved site plans containing separate native growth protection easements or tracts, and shall also be recorded as a covenant running with the land on the title of record for all affected lots on the title: “MAINTENANCE RESPONSIBILITY: All owners of lots created by or benefiting from this City action abutting or including a native growth protection easement [tract] are responsible for maintenance and protection of the easement [tract]. Maintenance includes ensuring that no alterations occur within the tract and that all vegetation remains undisturbed unless the express written authorization of the City has been received.”

5. Discretionary – Building or Development Setbacks: A building or activity setback from a critical area or buffer may be required to ensure adequate protection of the critical area/buffer during construction and ongoing maintenance of the activity. A requirement for a setback shall be based on the findings of a critical area report or a peer review required for the activity. (Ord. 5137, 4-25-2005; Ord. 5676, 12-3-2012)

F. SUBMITTAL REQUIREMENTS AND FEES:

1. Applicability: When a regulated critical area or associated buffer is identified, the following procedures apply.

2. Preapplication Consultation: Any person intending to develop properties known or suspected to have critical areas present is strongly encouraged to meet with the appropriate City department representative during the earliest possible stages of project planning before major commitments have been made to a particular land use and/or project design. Effort put into a preapplication consultation and planning will help applicants create projects which will be more quickly and easily processed due to a better understanding on the part of applicants of regulatory requirements.

3. Plans and Studies Required: When an application is submitted for any building permit or land use review and/or to obtain approval of a use, development or construction, the location of the critical areas and buffers on the site shall be indicated on the plans submitted based upon an inventory provided by a qualified specialist.

4. Submittal Requirements: See chapter 4-8 RMC.

5. Fees: See RMC 4-1-170.

6. Waiver of Submittal or Procedural Requirements: The Department Administrator may waive any of the requirements of this subsection if the size and complexity of the project does not warrant a step in the proceeding and provided criteria to waive studies are met in subsections H to M of this Section.

7. Independent Secondary Review: The City may require independent review of an applicant’s report as follows:

a. Aquifer Protection Areas, Flood Hazards, Habitat Conservation, Streams and Lakes, Wetlands: When appropriate due to the type of critical areas, habitat, or species present, or project area conditions, the applicant may be required to prepare and/or fund analyses or activities, including, but not limited to:

i. An evaluation by an independent qualified professional regarding the applicant’s analysis and the effectiveness of any proposed mitigating measures or programs, to include any recommendations as appropriate. This shall be paid at the applicant’s expense, and the Administrator shall select the third-party review professional; and/or

ii. A request for consultation with the Washington Department of Fish and Wildlife, Washington State Department of Ecology, or the local Native American Tribe or other appropriate agency; and/or

iii. Detailed surface and subsurface hydrologic features both on and abutting the site. (Ord. 5676, 12-3-2012)

b. Geologic Hazards: Independent secondary review shall be conducted in accordance with the following:

i. Required – Sensitive and Protected Slopes, and Medium, High, or Very High Landslide Hazards: All geotechnical reports submitted in accordance with subsection J2 of this Section, Special Studies Required, and chapter 4-8 RMC, Permits – General and Appeals, shall be independently reviewed by qualified specialists selected by the City, at the applicant’s expense. An applicant may request that independent review be waived by the Department Administrator in accordance with subsection D4b of this Section, Review Authority – Geologic Hazards, Habitat Conservation, Shorelines, Streams and Lakes, and Wetlands.

ii. Required for Critical Facilities in Volcanic, High Erosion, High Seismic, Medium Coal Mine, or High Coal Mine Hazards: The City shall require independent review of a geotechnical report addressing a critical facility by qualified specialists selected by the City, at the applicant’s expense. An applicant may request that independent review be waived by the Department Administrator in accordance with subsection D4b of this Section, Review Authority – Geologic Hazards, Habitat Conservation, Shorelines, Streams and Lakes, and Wetlands.

iii. At City’s Discretion – Volcanic, High Erosion, High Seismic, Medium Coal Mine, or High Coal Mine Hazards: For any proposal except critical facilities, the City may require independent review of an applicant’s geotechnical report by qualified specialists selected by the City, at the applicant’s expense.

8. Mitigation Plan Required:

a. Criteria: For any mitigation plans required through the application of subsections H to M of this Section, the applicant shall:

i. Demonstrate sufficient scientific expertise, the supervisory capability, and the financial resources to carry out the mitigation project; and

ii. Demonstrate the capability for monitoring the site and to make corrections during the monitoring period if the mitigation project fails to meet projected goals; and

iii. Protect and manage, or provide for the protection and management, of the mitigation area to avoid further development or degradation and to provide for long-term persistence of the mitigation area; and

iv. Provide for project monitoring and allow City inspections; and

v. Avoid mitigation proposals that would result in additional future mitigation or regulatory requirements for adjacent or abutting properties, unless it is a result of a code requirement, or no other option is feasible or practical; and (Ord. 5676, 12-3-2012)

vi. For on-site or off-site mitigation proposals, abutting or adjacent property owners shall be notified when wetland creation or restoration, stream relocation, critical area buffer increases, flood hazard mitigation, habitat conservation mitigation, or geologic hazard mitigation have the potential to considerably decrease the development potential of abutting or adjacent properties. For example, if a created wetland on a property would now result in a wetland buffer intruding onto a neighboring property, the neighboring property owner would be notified. Notification shall be given as follows:

(a) For applications that are not subject to notices of application per chapter 4-8 RMC, notice of the mitigation proposal shall be given by posting the site and notifying abutting or adjacent property owners with the potential to be impacted. Written notification may be made prior to or at the time of the SEPA determination.

(b) For applications that are subject to notices of application, the mitigation proposal shall be identified in the notice of application and mailed to abutting or adjacent property owners with the potential to be impacted; if the determination of the mitigation requirements is not known at the time of the notice of application, written notice to abutting or adjacent property owners shall be given instead at the time of the SEPA determination.

b. Timing of Mitigation Plan – Final Submittal and Commencement: When a mitigation plan is required, the proponent shall submit a final mitigation plan for the approval of the Administrator prior to the issuance of building or construction permits for development. The proponent shall receive written approval of the mitigation plan prior to commencement of any mitigation activity. (Ord. 5137, 4-25-2005)

G. SURETY DEVICES:

1. Required for Mitigation Plans: For any mitigation plans required as a result of the application of these regulations, a surety device shall be required to ensure performance consistent with RMC 4-1-230. (Ord. 5676, 12-3-2012)

2. Time Period – Wetlands, Streams, and Lakes: For wetland and/or stream/lake mitigation plans, the surety device shall be sufficient to guarantee that structures, improvements, and mitigation required by permit condition perform satisfactorily for a minimum of five (5) years after they have been completed. (Ord. 5137, 4-25-2005)

H. AQUIFER PROTECTION:

1. Applicability: The aquifer protection regulations apply to uses, activities, and facilities located within an aquifer protection area (APA) as classified below.

a. Aquifer Protection Area (APA): Aquifer protection areas are the portion of an aquifer within the zone of capture and recharge area for a well or well field owned or operated by the City, as depicted in subsection Q1 of this Section, Maps.

b. Aquifer Protection Zones: Zones of an APA are designated to provide graduated levels of aquifer protection. Zone boundaries are determined using best available science documented in the City of Renton Wellhead Protection Plan, an appendix of the City of Renton Water System Plan, as periodically updated. The following zones may be designated:

i. Zone 1: The land area situated between a well or well field owned by the City and the three hundred sixty five (365) day groundwater travel time contour.

ii. Zone 1 Modified: The same land area described for Zone 1 but for the purpose of protecting a high-priority well, wellfield, or spring withdrawing from an aquifer that is partially protected by overlying geologic strata. Uses, activities, and facilities located in this area are regulated as if located within Zone 1 except as provided by subsection C6(a)(iii) of this Section.

iii. Zone 2: The land area situated between the three hundred sixty five (365) day groundwater travel time contour and the boundary of the zone of potential capture for a well or well field owned or operated by the City. If the aquifer supplying water to a well, well field, or spring is naturally protected by overlying geologic strata, the City may choose not to subdivide an APA into two (2) zones. In such a case, the entire APA will be designated as Zone 2.

c. Mapping:

i. Determination of Location within a Zone of an Aquifer Protection Area: In determining the location of facilities within the zones defined by subsection Q1 of this Section, the following rules shall apply:

(a) Facilities located wholly within an APA zone shall be governed by the restrictions applicable to that zone.

(b) Facilities having parts lying within more than one zone of an APA shall be governed as follows: Each part of the facility shall be reviewed and regulated by the requirements set forth in this Section for the zone in which that part of the facility is actually located.

(c) Facilities having parts lying both in and out of an APA shall be governed as follows:

ii. Zone Maps: The locations of aquifer protection areas (APA) in the City are depicted by the map in subsection Q1 of this Section, Maps.

d. Performance Standards: In addition to the general standards of subsection E of this Section, the following performance standards, subsections H2 to H10, apply to all non-exempt uses, activities, and facilities on sites located within an aquifer protection area per subsection H1, Applicability.

e. Authority to Require Hydrogeologic Assessment: The City may require an applicant to prepare a hydrogeologic study if the proposal has the potential to significantly impact groundwater quantity or quality, and sufficient information is not readily available. Such a report shall be prepared by a qualified professional at the applicant’s expense. Report content requirements may be specified by the City in accordance with State or Federal guidelines or tailored to the particular development application. Peer review of the applicant’s report may be required in accordance with subsection F7 of this Section.

2. Facilities:

a. Removal of Existing Facilities – Zone 1:

i. The storage, handling, use, treatment or production of hazardous materials in aggregate quantities greater than five hundred (500) gallons shall not be allowed within Zone 1 of an APA after October 14, 2002. The storage, handling, use, treatment or production of tetrachloroethylene (e.g., dry-cleaning fluid) shall not be allowed within Zone 1 of an APA after March 31, 1999.

ii. Once a facility in Zone 1 is closed, relocated, or the use of hazardous materials is terminated, reinstatement of the use of hazardous materials on the site in quantities greater than that allowed for new facilities locating in Zone 1 as described in subsection C8d(i) of this

Section, Prohibited Activities, Zone 1, shall be prohibited.

iii. Closure of a facility or termination of any or all facility activities shall be conducted in accordance with the closure requirements in RMC 4-9-015F, Closure Permit.

b. Existing Facilities Change in Quantities – Zone 1: In Zone 1 of an APA, no change in operations at a facility shall be allowed that increases the aggregate quantity of hazardous materials stored, handled, treated, used, or produced with the following exception: The aggregate quantity of hazardous materials may be increased not to exceed five hundred (500) gallons.

c. Existing Facilities – Allowances in Zone 2: The storage, handling, treatment, use or production of hazardous materials at existing facilities shall be allowed within Zone 2 of an APA upon compliance with the provisions of this Section.

d. Requirements for Facilities – Zones 1 and 2: The following conditions in subsections H2d(i) to (vi) of this Section will be required as part of any operating permit issued for facilities in Zone 1 of an APA. Conditions in subsections H2d(i) to (v) of this Section shall apply to facilities in Zone 2 of an APA.

i. Secondary Containment – Zones 1 and 2:

(a) Materials Stored in Tanks subject to DOE – Zones 1 and 2: Hazardous materials stored in tanks that are subject to regulation by the Washington Department of Ecology under chapter 173-360 WAC are exempt from containment requirements in subsection H2d(i) of this Section, Secondary Containment – Zones 1 and 2, but are subject to applicable requirements in RMC 4-5-120, Underground Storage Tank Secondary Containment Regulations.

(b) Secondary Containment Devices and Requirements – Zones 1 and 2: Every owner of a facility shall provide secondary containment devices adequate in size to contain on-site any unauthorized release of hazardous materials from any area where these substances are either stored, handled, treated, used, or produced. Secondary containment devices shall prevent hazardous materials from contacting soil, surface water, and groundwater and shall prevent hazardous materials from entering storm drains and, except for authorized and permitted discharges, the sanitary sewer. Design requirements for secondary containment devices are as follows:

(1) The secondary containment device shall be large enough to contain the volume of the primary container in cases where a single container is used to store, handle, treat, use, or produce a hazardous material. In cases where multiple containers are used, the secondary containment device shall be large enough to contain the volume of the largest container. Volumes specified are in addition to the design flow rate of the automatic fire extinguishing system, if present, to which the secondary containment device is subjected. The secondary containment device shall be capable of containing the fire flow for a period of twenty (20) minutes or more.

(2) All secondary containment devices shall be constructed of materials of sufficient thickness, density, and composition to prevent structural weakening of the containment device as a result of contact with any hazardous material. If coatings are used to provide chemical resistance for secondary containment devices, they shall also be resistant to the expected abrasion and impact conditions. Secondary containment devices shall be capable of containing any unauthorized release for at least the maximum anticipated period sufficient to allow detection and removal of the release.

(3) Hazardous materials stored outdoors and their attendant secondary containment devices shall be covered to preclude precipitation with the exception of hazardous materials stored in tanks that have been approved by and are under permit from the City of Renton Fire Prevention Bureau. Secondary containment for such tanks, if uncovered, shall be able to accommodate the volume of precipitation that could enter the containment device during a twenty four (24) hour, twenty five (25) year storm, in addition to the volume of the hazardous material stored in the tank. Storage of hazardous materials, both indoors and outdoors, shall, at all times, meet both the requirements of this Section and the Uniform Fire Code.

(4) Secondary containment devices shall include monitoring procedures or technology capable of detecting the presence of a hazardous material within twenty four (24) hours following a release. Hazardous materials shall be removed from the secondary containment device within twenty four (24) hours of detection and shall be legally stored or disposed.

(5) Areas in which there are floor drains, catchbasins, or other conveyance piping that does not discharge into a secondary containment device that meets the requirements of this Chapter shall not be used for secondary containment of hazardous materials. Closure of existing piping shall be according to procedures and designs approved by the Department.

(6) Primary containers shall be impervious to the contents stored therein, properly labeled, and fitted with a tight cover which is kept closed except when substances are being withdrawn or used.

(7) Hazardous materials stored outdoors when the facility is left unsupervised must be inaccessible to the public. Such techniques as locked storage sheds, locked fencing, or other techniques may be used if they will effectively preclude access.

(8) Stored hazardous materials shall be protected and secured, as needed, against impact and earthquake to prevent damage to the primary container that would result in release of hazardous materials that would escape the secondary containment area.

ii. Hazardous Material Monitoring Requirements for Existing Facilities – Zones 1 and 2:

(a) The owners of all existing facilities shall implement hazardous materials monitoring.

(b) All hazardous material monitoring activities shall include the following:

(1) A written routine monitoring procedure which includes, when applicable: the frequency of performing the monitoring method, the methods and equipment to be used for performing the monitoring, the location(s) from which the monitoring will be performed, the name(s) or title(s) of the person(s) responsible for performing the monitoring and/or maintaining the equipment, and the reporting format.

(2) Written records of all monitoring performed shall be maintained on-site by the operator for a period of three (3) years from the date the monitoring was performed. The Department may require the submittal of the monitoring records or a summary at a frequency that the Department may establish. The written records of all monitoring performed in the past three (3) years shall be shown to the Department upon demand during any site inspection. Monitoring records shall include but not be limited to:

(3) Visual monitoring must be implemented unless it is determined by the Department to be infeasible to visually monitor.

(c) On every day of operation, a responsible person designated by the permittee shall check for breakage or leakage of any container holding hazardous materials. Electronic sensing devices approved by the Department may be employed as part of the inspection process; provided, that the system is checked daily for malfunctions.

iii. Emergency Collection Devices – Zones 1 and 2: Vacuum suction devices, absorbent scavenger materials, or other devices approved by the Department shall be present on site (or available within an hour by contract with a cleanup company approved by the Department), in sufficient quantity to control and collect the total quantity of hazardous materials plus absorbent material. The presence of such emergency collection devices and/or cleanup contract are the responsibility and at the expense of the owner and shall be documented in the operating permit.

iv. Inspection of Containment and Emergency Equipment – Zones 1 and 2: Owners shall establish procedures for monthly in-house inspection and routine maintenance of containment and emergency equipment. Such procedures shall be in writing, a regular checklist and schedule of maintenance activity shall be established, and a log shall be kept of inspections and maintenance activities. Such logs and records shall be made available at all reasonable times to the Department for examination.

v. Employee Training – Zones 1 and 2: Operators shall schedule training for all new employees upon hiring and once per year thereafter to explain the conditions of the operating permit such as emergency response procedures, proper hazardous waste disposal, monitoring and reporting requirements, record keeping requirements, and the types and quantities of hazardous materials on site. These training sessions will be documented and recorded and the names of those in attendance will be recorded. These records shall be made available at all reasonable times to the Department for inspection.

vi. Additional Facility Requirements for Zone 1: Owners shall complete the following:

(a) Site Monitoring: For facilities located in Zone 1 of an APA, an owner of a facility may, at their own expense, be required to institute a program to monitor groundwater, surface water runoff, and/or site soils. The Department may require that the owner of a facility install one or more groundwater monitoring wells in a manner approved by the Department in order to accommodate the required groundwater monitoring. Criteria used to determine the need for site monitoring shall include, but not be limited to, the proximity of the facility to the City’s production or monitoring wells, the type and quantity of hazardous materials on site, and whether or not the hazardous materials are stored in underground vessels.

Every owner required to monitor groundwater, surface water runoff, and/or soils shall perform such monitoring semi-annually and obtain independent analytical results of the presence and concentration of those chemicals requiring monitoring (including breakdown and transformation products) as identified by the Department in the operating permit. The analytical results shall be obtained through the use of Department of Ecology-approved methods for water and/or soils. The results shall be filed within ten (10) days with the Department.

If a facility is required to perform site monitoring pursuant to subsection H2d(vi) of this Section, Additional Facility Requirements for Zone 1, Site Monitoring, then a site monitoring plan will be required. This plan must indicate procedures to be followed to assess groundwater, surface water runoff, and/or soil for concentrations of those chemicals requiring monitoring as identified by the Department in the operating permit. If a groundwater monitoring program is in effect per the requirements of 40 CFR 264 or 265, and this program includes all of the chemicals identified in the operating permit, then it shall be incorporated into the site monitoring plan which shall also include provisions to address the groundwater monitoring requirements of subsection H2d(vi) of this Section, Additional Facility Requirements for Zone 1, Site Monitoring, and RMC 4-9-015G3, Unauthorized Releases, Monitoring Results.

(b) Site Improvements:

(1) For facilities located in Zone 1 of an APA, the owner may be required to pave all currently unpaved areas of their facility that are subject to any vehicular use or storage, use, handling, or production of hazardous materials.

(2) For those facilities located in Zone 1 of an APA in which the nature of the business involves the use of hazardous materials outside of fully enclosed structures, the City shall evaluate the existing stormwater collection and conveyance system, and reserves the right to require the owner to upgrade the system to meet the provisions of RMC 4-6-030E4f, Special Requirement 6 – Aquifer Protection Area (APA).

(3) For those facilities located in Zone 1 of an APA, the City may require the owner to test interior wastewater plumbing and the building side sewer for tightness according to subsection H6a(ii) of this Section, Pipeline Requirements – Zone 1, and reserves the right to require that such wastewater conveyance be repaired or replaced according to subsection H6a(i) of this Section, Pipeline Requirements – Zone 1. (Ord. 5526, 2-1-2010)

(c) Capital Cost Reimbursement for Additional Operating Permit Requirements: The City shall pay fifty percent (50%) of documented capital costs up to twenty five thousand dollars ($25,000.00) for required installation and construction of monitoring wells, site paving, wastewater conveyance, and stormwater improvements as required in subsections H2d(vi)(a) and (b) of this Section, Site Monitoring and Site Improvements. Payment by the City shall be made according to adopted administrative rules.

3. Use of Pesticides and Nitrates – APA Zones 1 and 2:

a. Use of Pesticides: The application of hazardous materials such as pesticides shall be allowed in an APA, except within one hundred feet (100') of a well or two hundred feet (200') of a spring; provided, that:

i. The application is in strict conformity with the use requirements as set forth by the EPA and as indicated on the containers in which the substances are sold.

ii. Persons who are required to keep pesticide application records by RCW 17.21.100.1 and WAC 16-228-190 shall provide a copy of the required records to the Department within seventy two (72) hours of the application.

b. Nitrate-Containing Materials: The application of fertilizers containing nitrates shall be allowed in an APA except within one hundred feet (100') of a well or two hundred feet (200') of a spring; provided, that:

i. No application of nitrate-containing materials shall exceed one-half (0.5) pound of nitrogen per one thousand (1,000) square feet per single application and a total yearly application of five (5) pounds of nitrogen per one thousand (1,000) square feet; except that an approved slow-release nitrogen may be applied in quantities of up to nine-tenths (0.9) pound of nitrogen per one thousand (1,000) square feet per single application and eight (8) pounds of nitrogen per one thousand (1,000) square feet per year; and

ii. Persons who apply fertilizer containing nitrates to more than one contiguous acre of land located in the APA either in one or multiple application(s) per year shall provide to the Department within seventy two (72) hours of any application the following information:

(a) The name, address, and telephone number of the person applying the fertilizer;

(b) The location and land area of the application;

(c) The date and time of the application;

(d) The product name and formulation;

(e) The application rate.

4. Wastewater Disposal Requirements – Zones 1 and 2: Refer to RMC 4-6-040J, Sanitary Sewer Standards, Additional Requirements that Apply within Zones 1 and 2 of an Aquifer Protection Area.

5. Surface Water Requirements – Zones 1 and 2: Refer to RMC 4-6-030E, Drainage Plan Requirements and Methods of Analysis for additional surface water requirements applicable within Zones 1 and 2 of an Aquifer Protection Area.

6. Pipeline Requirements:

a. Pipeline Requirements – Zone 1:

i. All new and existing pipelines in Zone 1 shall be constructed or repaired in accordance with material specifications contained in subsection S of this Section, Pipeline Material. All existing product pipelines in Zone 1 shall be repaired and maintained in accordance with best management practices and best available technology.

ii. All new pipelines constructed in Zone 1 shall be tested for leakage in conformance with the following provisions prior to being placed into service.

(a) Pipeline leakage testing shall be conducted in accordance with best available technology, to the satisfaction of the Department.

(b) Pipeline leakage testing methods shall be submitted to the Department for review prior to testing and shall include a detailed description of the testing methods and technical assumptions; accuracy and precision of the test; proposed testing durations, pressures, and lengths of pipeline to be tested; and scale drawings of the pipeline(s) to be tested.

(c) Upon completion of testing, pipeline leakage testing results shall be submitted to the Department and shall include: record of testing durations, pressures, and lengths of pipeline tested; and weather conditions at the time of testing.

(d) Routine leakage testing of new pipelines constructed in Zone 1 may be required by the Department.

iii. If the Department has reason to believe that the operation or proposed operation of an existing pipeline in Zone 1 of an APA may degrade groundwater quality, the Department may require leakage testing of the existing pipeline in accordance with subsection H6a(ii) of this Section; and installation, sampling, and sample analysis of monitoring wells. Routine leakage testing of existing pipelines in Zone 1 may be required by the Department. Criteria for this determination is specified under subsection D2b(ii) of this Section, Potential to Degrade Groundwater – Zone 2, Criteria.

iv. Should pipeline leakage testing reveal any leakage at any level then the Department shall require immediate repairs to the pipeline to the satisfaction of the Department such that no infiltration of water into the pipeline or exfiltration of substances conveyed in the pipeline shall occur. Any repairs which are made shall be tested for leakage pursuant to subsection H6a(ii) of this Section.

b. Pipeline Requirements – Zone 2: If the Department has reason to believe that the operation or proposed operation of an existing pipeline in Zone 2 of an APA may degrade groundwater quality, the Department may require leakage testing in accordance with subsection H6a(ii) of this Section; installation, sampling, and sample analysis of groundwater monitoring wells; repair of the pipeline to the satisfaction of the Department such that degradation of groundwater quality is minimized or eliminated. Criteria for this determination is specified under subsection D2b(ii), Potential to Degrade Groundwater – Zone 2, Criteria.

7. Construction Activity Standards – Zones 1 and 2: Refer to RMC 4-4-030C8, Construction Activity Standards – APA Zones 1 and 2.

8. Fill Material Requirements – Zones 1 and 2: Refer to RMC 4-4-060L4, Fill Material, regarding quality of fill and fill material source statement requirements within aquifer protection areas.

9. Regulations for Existing Solid Waste Landfills – Zones 1 and 2:

a. Materials: Earth materials used as fill or cover at a solid waste landfill shall meet the requirements of RMC 4-4-060L4, Fill Material.

b. Groundwater Monitoring: The Department shall have the authority to require an owner of a solid waste landfill to implement a groundwater monitoring program equal to that described by King County Board of Health Title 10 (King County Solid Waste Regulations) Section 10.72.020 and a corrective action program equal to that described by Section 10.72.030. The Department shall have the authority ascribed to the health officer in said regulations. Quarterly reports shall be provided to the Department detailing groundwater monitoring activity during the preceding three (3) months. Reports detailing corrective action required by the Department shall be submitted according to a written schedule approved by the Department.

10. Hazardous Materials – Release Restrictions – Zones 1 and 2: Hazardous materials shall not be spilled, leaked, emitted, discharged, disposed, or allowed to escape or leach into the air, into groundwater, surface water, surface soils or subsurface soils. Exception: Intentional withdrawals of hazardous materials for the purpose of legitimate sale, use, or disposal and discharges permitted under federal, state, or local law. Any unauthorized releases shall be subject to the procedural requirements of RMC 4-9-015G, Unauthorized Releases. (Ord. 4851, 8-7-2000; Ord. 4992, 12-9-2002; Ord. 5137, 4-25-2005)

I. FLOOD HAZARDS:

1. Applicability: Flood hazard regulations shall apply to all areas of special flood hazards within the jurisdiction of the City. In addition, all other applicable critical area or Shoreline Master Program regulations shall apply within flood hazard areas. See RMC 4-3-090E for a description of Shoreline Master Program jurisdictional areas.

a. Areas of Special Flood Hazard: Areas of special flood hazard are defined as the land in the floodplain subject to one percent or greater chance of flooding in any given year. Designation on flood maps always include the letters A or V.

b. Mapping and Documentation:

i. Basic Map and Documentation Identifying Hazards: The areas of special flood hazard are identified by the Federal Insurance Administration in a scientific and engineering report entitled the Flood Insurance Study for the City of Renton, dated September 29, 1989, and any subsequent revision, with accompanying flood insurance maps which are hereby adopted by reference and declared to be a part of this section. The flood insurance study is on file at the Public Works Department. (Ord. 5450, 3-2-2009)

ii. When Federal Insurance Study is Not Available: When base flood elevation data has not been provided in accordance with subsection I1b(i) of this Section the Department Administrator shall obtain, review, and reasonably utilize any base flood elevation and floodway data available from a Federal, State or other source in order to administer subsection I3 of this Section, Specific Standards, and subsection I4 of this Section, Additional Restrictions Within Floodways. The best available information for flood hazard area identification shall be the basis for regulation until a new Flood Insurance Rate Map is issued which incorporates the data utilized under subsection D3a(iv) of this Section.

iii. Interpretation of FIRM Boundaries: Per subsection D3d of this Section, the Administrator shall make interpretations where needed, as to the exact location of the boundaries of the areas of special flood hazard (for example, where there appears to be a conflict between a mapped boundary and actual field conditions). The best available information for flood hazard area identification shall be the basis for regulation. (Ord. 5676, 12-3-2012)

iv. Data to be Used for Existing and Future Flow Conditions: The City shall determine the components of the flood hazard area after obtaining, reviewing and utilizing base flood elevations and available floodplain data for a flood having a one percent chance of being equaled or exceeded in any given year, often referred to as the “one-hundred-year flood.” The City may require projections of future flow conditions for proposals in unmapped potential flood hazard areas. In mapped or unmapped flood hazard areas, future flow conditions shall be considered for proposed bridge proposals crossing floodways.

c. Performance Standards: In addition to general standards of subsection E of this Section, the following regulations, subsections I2 through I4 of this Section, apply in all areas of special flood hazard.

2. General Standards: In all areas of special flood hazards, the following standards are required:

a. Anchoring – All New Construction: All new construction and substantial improvements shall be anchored to prevent flotation, collapse, or lateral movement of the structure.

b. Anchoring – Manufactured Homes: All manufactured homes must likewise be anchored to prevent flotation, collapse or lateral movement, and shall be installed using methods and practices that minimize flood damage. Anchoring methods may include, but are not limited to, use of over-the-top or frame ties to ground anchors (reference FEMA’s Manufactured Home Installation in Flood Hazard Areas guidebook for additional techniques).

c. Construction Materials and Methods:

i. All new construction and substantial improvements shall be constructed with materials and utility equipment resistant to flood damage.

ii. All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage.

iii. Electrical, heating, ventilation, plumbing, and air-conditioning equipment and other service facilities shall be designed and/or otherwise elevated or located so as to prevent water from entering or accumulating within the components during conditions of flooding.

d. Utilities:

i. Water: All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of flood waters into the system. The proposed water well shall be located on high ground that is not in the floodway (WAC 173-160-171).

ii. Sewer: New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of flood waters into the systems and discharge from the systems into flood waters.

iii. Waste Disposal: On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.

e. Subdivision Proposals:

i. All subdivision proposals shall be consistent with the need to minimize flood damage;

ii. All subdivision proposals shall have public utilities and facilities such as sewer, gas, electrical, and water systems located and constructed to minimize flood damage;

iii. All subdivision proposals shall have adequate drainage provided to reduce exposure to flood damage; and

iv. All subdivision proposals shall show the flood hazard information and boundary on the subdivision drawing including the nature, location, dimensions, and elevations of the subdivided area.

f. Project Review:

i. Building Permits: Where elevation data is not available either through the flood insurance study or from another authoritative source, i.e., subsection D3a(iv) of this Section, applications for building permits shall be reviewed to assure that proposed construction will be reasonably safe from flooding. The test of reasonableness is a local judgment and includes use of historical data, high water marks, photographs of past flooding, etc., where available. Failure to elevate at least two feet (2') above grade in these zones may result in higher insurance rates.

ii. Land Use Applications: Where base flood elevation data has not been provided or is not available from another authoritative source, it shall be generated for subdivision proposals and other proposed developments which contain at least fifty (50) lots or five (5) acres (whichever is less).

3. Specific Standards: In all areas of special flood hazards where base flood elevation data has been provided as set forth in subsection I1b of this Section, Mapping and Documentation, or subsection D3a(iv) of this Section, Use of Other Base Flood Data, where such data provides flood elevations that exceed the regulatory standards in the FEMA flood insurance study, the following provisions are required:

a. Residential Construction:

i. New construction and substantial improvement of any residential structure shall have the lowest floor, including basement, elevated a minimum of one foot (1') above base flood elevation.

ii. Fully enclosed areas below the lowest floor that are subject to flooding are prohibited, or shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of flood waters. Designs for meeting this requirement must either be certified by a registered professional engineer or architect or must meet or exceed the following minimum criteria:

(a) A minimum of two (2) openings having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding shall be provided; and

(b) The bottom of all openings shall be no higher than one foot above grade; and

(c) Openings may be equipped with screens, louvers, or other coverings or devices; provided, that they permit the automatic entry and exit of flood waters.

b. Manufactured Homes:

i. All manufactured homes to be placed or substantially improved within Zones A1-A30, AH, and AE on the community’s Flood Insurance Rate Map, on sites outside of a manufactured home park or subdivision, in a new manufactured home park or subdivision, in an expansion to an existing manufactured home park or subdivision, or in an existing manufactured home park or subdivision on which a manufactured home has incurred “substantial damage” as the result of a flood, shall be elevated on a permanent foundation such that the lowest floor of the manufactured home is elevated a minimum of one foot above the base flood elevation and be securely anchored to an adequately anchored foundation system to resist flotation, collapse and lateral movement.

ii. Manufactured homes to be placed or substantially improved on sites in an existing manufactured home park or subdivision within Zones A1-30, AH, and AE on the community’s Flood Insurance Rate Map that are not subject to the above manufactured home provisions shall be elevated so that either the lowest floor of the manufactured home is elevated a minimum of one foot (1') above the base flood elevation or the manufactured home chassis is supported by reinforced piers or other foundation elements of at least equivalent strength that are no less than thirty six inches (36") in height above grade and be securely anchored to an adequately anchored foundation system to resist flotation, collapse, and lateral movement.

c. Nonresidential Construction: New construction of any commercial, industrial or other nonresidential structure shall have the lowest floor, including basement, elevated a minimum of one foot (1') above the level of the base flood elevation. Substantial improvement of any commercial, industrial or other nonresidential structure shall have the lowest floor, including basement, elevated a minimum of one foot (1') above the level of the base flood elevation, or, together with attendant utility and sanitary facilities, shall:

i. Be floodproofed so that below the minimum elevation required in subsection I3c of this Section the structure is watertight with walls substantially impermeable to the passage of water;

ii. Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy;

iii. Be certified by a registered professional engineer or architect that the design and methods of construction are in accordance with accepted standards of practice for meeting provisions of this subsection based on their development and/or review of the structural design, specifications and plans. Such certifications shall be provided to the Department Administrator;

iv. Nonresidential structures that are elevated, not floodproofed, must meet the same standards for space below the lowest floor as described in subsection I3a(ii) of this Section;

v. Applicants floodproofing nonresidential buildings shall be notified that flood insurance premiums will be based on rates that are one foot (1') below the floodproofed level (e.g., a building floodproofed to the base flood level will be rated as one foot (1') below).

d. Recreational Vehicles: Recreational vehicles placed on sites within Zones A1-30, AH, and AE on the community’s Flood Insurance Rate Map not including recreational vehicle storage lots shall either:

i. Be on the site for fewer than one hundred eighty (180) consecutive days;

ii. Be fully licensed and ready for highway use, on its wheels or jacking system, is attached to the site only by quick disconnect type utilities and security devices, and has no permanently attached additions; or

iii. Meet the requirements of subsection I3b of this Section and the elevation and anchoring requirements for manufactured homes.

4. Additional Restrictions within Floodways: Located within areas of special flood hazard established in subsection I1b of this Section, Flood Hazards: Mapping and Documentation, are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of flood waters which carry debris, potential projectiles, and erosion potential, the following provisions apply:

a. Increase in Flood Levels Prohibited: Encroachments, including fill, new construction, substantial improvements, and other development are prohibited unless certification by a registered professional engineer demonstrates through hydrologic and hydraulic analyses performed in accordance with standard engineering practice that:

i. Encroachments shall not result in any increase in flood levels during the occurrence of the base flood discharge; and

ii. There are no adverse impacts to the subject property or abutting or adjacent properties; and

iii. There are no higher flood elevations upstream; and

iv. The impact due to floodway encroachment shall be analyzed using future land use condition flows.

b. Residential Construction in Floodways: Construction or reconstruction of residential structures is prohibited within designated floodways, except for:

i. Repairs, reconstruction, or improvements to a structure which do not increase the ground floor area; and

ii. Repairs, reconstruction or improvements to a structure, the cost of which does not exceed fifty percent (50%) of the market value of the structure either: (a) before the repair, reconstruction, or improvement is started; or (b) if the structure has been damaged, and is being restored, before the damage occurred. Work done on structures to comply with existing health, sanitary, or safety codes or to structures identified as historic places may be excluded in the fifty percent (50%).

c. Compliance Requirements: If subsections I4a and I4b of this Section are satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of this Section.

5. Critical Facility: Construction of new critical facilities shall be, to the extent possible, located outside the limits of the special flood hazard area (SFHA) (one hundred (100) year) floodplain. Construction of new critical facilities shall be permissible within the SFHA if no feasible alternative site is available. Critical facilities constructed within the SFHA shall have the lowest floor elevated three feet (3') or more above the level of the base flood elevation (one hundred (100) year) at the site. Floodproofing and sealing measures must be taken to ensure that toxic substances will not be displaced by or released into flood waters. Access routes elevated to or above the level of the base flood elevation shall be provided to all critical facilities to the extent possible.

6. Compensatory Storage:

a. Compensatory Storage Required: Development proposals and other alterations shall not reduce the effective base flood storage volume of the floodplain. If grading or other activity will reduce the effective storage volume, compensatory storage shall be created on the site or off the site if legal arrangements can be made to assure that the effective compensatory storage volume will be preserved over time. Compensatory storage shall be configured so as not to trap or strand salmonids after flood waters recede and may be configured to provide salmonid habitat or high flow refuge whenever suitable site conditions exist and the configuration does not adversely affect bank stability or existing habitat.

b. Additional Requirements – Springbrook Creek: The higher of the City hydrologic and hydraulic model results for the one hundred (100) year future land use conveyance and storage events shall be used by the City to determine the volume of compensatory storage required for filling within the one hundred (100) year flood zone of Springbrook Creek.

i. An exception to this requirement shall apply where the Federal Emergency Management Agency (FEMA) defined one hundred (100) year flood zone is lower than the City model results for the one hundred (100) year future land use conveyance event.

ii. Under the exception, the lower FEMA floodplain elevation shall be used. The exception only applies for the reach of Springbrook Creek between SW 43rd Street and Oakesdale Avenue near SW 41st Street.

c. Determining Finished Floor Elevations According to FEMA: Although City model results will apply to compensatory storage requirements, the FEMA one hundred (100) year flood plain elevations shall be used to establish building finished floor elevations to comply with other National Flood Insurance Program requirements. (Amd. Ord. 4851, 8-7-2000; Ord. 5137, 4-25-2005)

J. GEOLOGIC HAZARDS:

1. Applicability: The geologic hazard regulations apply to all nonexempt activities on sites containing steep slopes, landslide hazards, erosion hazards, seismic hazards, and/or coal mine hazards classified below or on sites within fifty feet (50') of steep slopes, landslide hazards, erosion hazards, seismic hazards, and/or coal mine hazards classified below which are located on abutting or adjacent sites.

a. Steep Slopes:

i. Steep Slope Delineation Procedure: The boundaries of a regulated steep sensitive or protected slope are determined to be in the location identified on the City of Renton’s Steep Slope Atlas. An applicant’s qualified professional may substitute boundaries independently derived from survey data for the City’s consideration in determining the boundaries of sensitive or protected steep slopes. All topographic maps shall utilize two foot (2') contour intervals or the standard utilized in the City of Renton Steep Slope Atlas.

ii. Steep Slope Types:

(a) Sensitive slopes.

(b) Protected slopes.

b. Landslide Hazards:

i. Low Landslide Hazard (LL): Areas with slopes less than fifteen percent (15%).

ii. Medium Landslide Hazard (LM): Areas with slopes between fifteen percent (15%) and forty percent (40%) and underlain by soils that consist largely of sand, gravel or glacial till.

iii. High Landslide Hazards (LH): Areas with slopes greater than forty percent (40%), and areas with slopes between fifteen percent (15%) and forty percent (40%) and underlain by soils consisting largely of silt and clay.

iv. Very High Landslide Hazards (LV): Areas of known mappable landslide deposits. 

c. Erosion Hazards:

i. Low Erosion Hazard (EL): Areas with soils characterized by the Natural Resource Conservation Service (formerly U.S. Soil Conservation Service) as having slight or moderate erosion potential, and that slope less than fifteen percent (15%).

ii. High Erosion Hazard (EH): Areas with soils characterized by the Natural Resource Conservation Service (formerly U.S. Soil Conservation Service) as having severe or very severe erosion potential, and that slope more steeply than fifteen percent (15%).

d. Seismic Hazards:

i. Low Seismic Hazard (SL): Areas underlain by dense soils or bedrock. These soils generally have site coefficients of types S1 or S2, as defined in the International Building Code.

ii. High Seismic Hazard (SH): Areas underlain by soft or loose, saturated soils. These soils generally have site coefficients of types S3 or S4, as defined in the International Building Code. (Ord. 5450, 3-2-2009)

e. Coal Mine Hazards:

i. Low Coal Mine Hazards (CL): Areas with no known mine workings and no predicted subsidence. While no mines are known in these areas, undocumented mining is known to have occurred.

ii. Medium Coal Mine Hazards (CM): Areas where mine workings are deeper than two hundred feet (200') for steeply dipping seams, or deeper than fifteen (15) times the thickness of the seam or workings for gently dipping seams. These areas may be affected by subsidence.

iii. High Coal Mine Hazard (CH): Areas with abandoned and improperly sealed mine openings and areas underlain by mine workings shallower than two hundred feet (200') in depth for steeply dipping seams, or shallower than fifteen (15) times the thickness of the seam or workings for gently dipping seams. These areas may be affected by collapse or other subsidence.

f. Volcanic Hazards: Volcanic hazard areas are those areas subject to a potential for inundation from post lahar sedimentation along the lower Green River as identified in Plate II, Map D, in the report U.S. Department of the Interior, U.S. Geological Survey (Revised 1998), Volcano Hazards from Mount Rainier, Washington. Open-File Report 98-428.

g. Mapping: Maps of steep slopes, landslide, erosion, seismic, and coal mine hazards are documented and included in subsection Q of this Section, Maps. The actual presence or absence of the criteria listed above, as determined by qualified professionals, shall govern the treatment of an individual building site or parcel of land requiring compliance with these regulations.

h. Performance Standards: In addition to the general standards of subsection E of this Section, the following performance standards, subsections J2 to J9 of this Section, apply to all regulated geologic hazard areas, unless the subsection clearly identifies that the standard applies only to a specific geologic hazard category. Multiple performance standards may apply to a site feature, for example steep slope, landslide and erosion hazards, based upon overlapping classification systems.

2. Special Studies Required:

a. Whenever a proposed development requires a development permit and a geologic hazard is present on the site of the proposed development or on abutting or adjacent sites within fifty feet (50') of the subject site, geotechnical studies by qualified professionals shall be required. Specifically, geotechnical studies are required for developments proposed on sites with any of the following geologic hazards:

i. Sensitive and protected slopes;

ii. Medium, high, or very high landslide hazards;

iii. High erosion hazards;

iv. High seismic hazards;

v. Medium or high coal mine hazards.

b. The required studies shall demonstrate the following review criteria can be met:

i. The proposal will not increase the threat of the geological hazard to adjacent or abutting properties beyond pre-development conditions; and (Ord. 5676, 12-3-2012)

ii. The proposal will not adversely impact other critical areas; and

iii. The development can be safely accommodated on the site.

c. A mitigation plan may be required consistent with subsection F8 of this Section. (Ord. 5676, 12-3-2012)

3.  Independent Secondary Review: Independent secondary review is required consistent with subsection F7 of this Section.

4. Conditions of Approval: Conditions of approval may modify the proposal, including, but not limited to, construction techniques, design, drainage, project size/configuration, or seasonal constraints on development. Additional possible conditions may be listed under the performance standards for each hazard type. Upon review of geotechnical studies, the development permit shall be conditioned to mitigate adverse environmental impacts and to assure that the development can be safely accommodated on the site and is consistent with the purposes of this Section. A mitigation plan may be required consistent with subsection F8 of this Section.

5. Protected Slopes:

a. Prohibited Development: Development is prohibited on protected slopes. This restriction is not intended to prevent the subdivision or development of property that includes forty percent (40%) or greater slopes on a portion of the site, provided there is enough developable area elsewhere to accommodate building pads.

b. Exceptions through Modification: Exceptions to the prohibition may be granted for:

i. Filling against the toe of a natural rock wall or rock wall, or protected slope created through mineral and natural resource recovery activities or public or private road installation or widening and related transportation improvements, railroad track installation or improvement, or public or private utility installation activities pursuant to subsection N2 of this Section, Modifications.

ii. Grading to the extent that it eliminates all or portions of a mound or to allow reconfiguration of protected slopes created through mineral and natural resource recovery activities or public or private road installation or widening and related transportation improvements, railroad track installation or improvement, or public or private utility installation activities, pursuant to subsection N2 of this Section, Modifications.

c. Exceptions through Variance: Exceptions to the prohibition may be granted for construction, reconstruction, additions, and associated accessory structures of a single family home on an existing legal lot pursuant to a variance as stated in RMC 4-9-250B1.

d. Exceptions through Waiver: Exceptions to the prohibition may be granted for installation of public utilities which are needed to protect slope stability, and public road widening where all the following provisions have been demonstrated:

i. The utility or road improvement is consistent with the Renton Comprehensive Plan, adopted utility plans, and the Transportation Improvement Program where applicable.

ii. Alternative locations have been determined to be economically or functionally infeasible.

iii. A geotechnical evaluation indicates that the proposal will not increase the risk of occurrence of a geologic hazard, and measures are identified to eliminate or reduce risks.

iv. The plan for the improvement is based on consideration of the best available science as described in WAC 365-195-905; or where there is an absence of valid scientific information, the steps in RMC 4-9-250F are followed.

Where the excepted activities above are allowed, the erosion control measures in subsection J6 of this Section, Sensitive Slopes, Medium, High and Very High Landslide Hazards, and High Erosion Hazards, shall also apply.

e. Native Growth Protection Areas – Protected Slopes: Unless development is allowed pursuant to subsections J5a through J5d of this Section, protected slopes shall be placed in a native growth protection area pursuant to subsection E4 of this Section, or dedicated to a conservation organization or land trust, or similarly preserved through a permanent protective mechanism acceptable to the City.

f. Conditions of Approval: Based upon the results of the geotechnical report and independent review, conditions of approval for developments on sites which include steep slopes may include, but are not limited to, vegetation enhancement, slope stabilization, buffer zones, or other requirements. Mitigation plans may be required consistent with subsection F8 of this Section.

g. Coordination with Stream and Lake Buffers: When a required stream/lake buffer falls within a protected slope area, the stream/lake buffer width shall extend to the boundary of the protected slope.

6. Sensitive Slopes – Medium, High and Very High Landslide Hazards – High Erosion Hazards: The following standards apply to development on sensitive slopes, medium/high/very high landslide hazard areas, and high erosion hazard areas:

a. Erosion Control Plans: Development applications shall submit erosion control plans consistent with subsection J2 of this Section, Special Studies Required, and chapter 4-8 RMC, Permits and Appeals.

b. Conditions of Approval: A development proposal may be conditioned to achieve minimal site erosion, including, but not limited to, timing of construction and vegetation stabilization, sequencing or phasing of construction, clearing and grading limits, and other measures. Mitigation plans may be required consistent with subsection F8 of this Section. (Ord. 5676, 12-3-2012)

c. On-Site Inspections: During construction, weekly on-site inspections shall be required at the applicant’s expense. Weekly reports documenting erosion control measures shall be required.

7. Very High Landslide Hazards:

a. Prohibited Development: Development shall not be permitted on land designated with very high landslide hazards, except by variance, administered pursuant to RMC 4-9-250B1, for construction of a single family home on an existing legal lot.

b. Buffer Requirement: A buffer of fifty feet (50') shall be established from the top, toe and sides of a very high landslide hazard area. The Department Administrator may increase or decrease the required buffer based upon the results of a geotechnical report, and any increase or decrease based upon the results of the geotechnical study shall be documented in writing and included with the project approval.

i. The modified standard shall be based on consideration of the best available science as described in WAC 365-195-905; or where there is an absence of valid scientific information, the steps in RMC 4-9-250F shall be followed. Notification may be required pursuant to subsection F8 of this Section.

ii. When a required stream/lake buffer falls within a very high landslide hazard area or buffer, the stream/lake buffer width shall extend to the boundary of the very high landslide hazard buffer.

c. Native Growth Protection Area – Very High Landslide Hazards: The landslide hazard area shall be placed in a native growth protection area pursuant to subsection E4 of this Section, or dedicated to a conservation organization or land trust, or similarly preserved through a permanent protective mechanism acceptable to the City. Based upon the results of the geotechnical study, the buffer may be placed in a native growth protection area, or it may be designated as a “no build” easement, or the area may be designated, in part, a native growth protection area and, in part, a “no build” easement.

8. Coal Mine Hazards:

a. Medium Hazard – Report Required: Reports consistent with subsection J2 of this Section, Special Studies Required, and chapter 4-8 RMC, Permits and Appeals, shall be prepared for development proposed within medium coal mine hazard areas and for development proposed within two hundred feet (200') of a medium coal mine hazard area. An applicant may request that the Department Administrator waive the report requirement pursuant to subsection D4b of this Section, Review Authority – Geologic Hazards, Habitat Conservation, Streams and Lakes, and Wetlands, where it has been determined through field documentation that coal mine hazards are not present.

b. High Hazard – Report Required: Reports consistent with subsection J2 of this Section, Special Studies Required, and chapter 4-8 RMC, Permits and Appeals, shall be prepared for development proposed within high coal mine hazard areas and for development proposed within five hundred feet (500') of a high coal mine hazard area. An applicant may request that the Department Administrator waive the report requirement pursuant to subsection D4b of this Section, Review Authority – Geologic Hazards, Habitat Conservation, Streams and Lakes, and Wetlands, where it has been determined through field documentation that coal mine hazards are not present.

c. Conditions of Approval: Based upon the results of studies prepared, the City may condition approval of development by requiring mitigation. Potential mitigation may include, but is not limited to, backfilling and sealing mine entries and shafts, backfilling existing sinkholes, removal or regrading or capping coal mine waste dumps, limiting development on portions of the site, or other measures offering equal protection from the hazard. A mitigation plan may be required consistent with subsection F8 of this Section.

i. Additional Engineering Design and Remediation Specifications: After approval of the mitigation approach proposed as a result of subsection J8c of this Section, and prior to construction, the applicant shall complete engineering design drawings and specifications for remediation. Upon approval of the plans and specifications, the applicant shall complete the remediation. Hazard mitigation shall be performed by or under the direction of a qualified engineer or geologist. The applicant shall document the hazard mitigation by submitting as-builts and a remediation construction report.

d. Hazards Found during Construction: Any hazards found during any development activities shall be immediately reported to the Development Services Division. Any coal mine hazards shall be mitigated prior to recommencing construction based upon supplemental recommendations or reports by the applicant’s geotechnical professional.

e. Construction in Areas with Combustion: Construction shall not be permitted where surface or subsurface investigations indicate the possible presence of combustion in the underlying seam or seams, unless the impact is adequately mitigated in accordance with the recommendations of the applicant’s geotechnical professional.

9. Volcanic Hazards: Critical facilities on sites containing areas susceptible to inundation due to volcanic hazards shall require an evacuation and emergency management plan. The applicant for critical facilities shall evaluate the risk of inundation or flooding resulting from mudflows originating on Mount Rainier in a geotechnical report, and identify any engineering or other mitigation measures as appropriate. Mitigation plans may be required consistent with subsection F8 of this Section. (Amd. Ord. 4835, 8-7-2000; Ord. 4851, 8-7-2000; Ord. 4963, 5-13-2002; Ord. 5137, 4-25-2005)

K. HABITAT CONSERVATION:

1. Applicability: The habitat conservation regulations apply to all nonexempt activities on sites containing or abutting critical habitat as classified below.

a. Critical Habitat: Critical habitats are those habitat areas which meet any of the following criteria:

i. Habitats associated with the documented presence of non-salmonid (see subsection L1 of this Section and RMC 4-3-090, Shoreline Master Program Regulations, for salmonid species) species proposed or listed by the Federal government or State of Washington as endangered, threatened, candidate, sensitive, monitor, or priority; and/or

ii. Category 1 wetlands (refer to subsection M1 of this Section for classification criteria).

b. Mapping:

i. Critical habitats are identified by lists, categories and definitions of species promulgated by the Washington State Department of Fish and Wildlife (Non-game Data System Special Animal Species) as identified in WAC 232-12-011; in the Priority Habitat and Species Program of the Washington State Department of Fish and Wildlife; or by rules and regulations adopted currently or hereafter by the U.S. Fish and Wildlife Service.

ii. Referenced inventories and maps are to be used as guides to the general location and extent of critical habitat. Critical habitat which is identified in subsection K1a of this Section, but not shown on the referenced inventories and maps, are presumed to exist in the City and are also protected under all the provisions of this Section.

iii. The actual presence or absence of the criteria listed above, as determined by qualified professionals, shall govern the treatment of an individual building site or parcel of land requiring compliance with these regulations.

c. Performance Standards: In addition to the general standards of subsection E of this Section, the following performance standards, subsections K2 to K5 of this Section, apply to all non-exempt activities on sites containing critical habitat areas per subsection K1a of this Section.

2. Habitat Assessment Required: Based upon subsection K1 of this Section, Applicability, the City shall require a habitat/wildlife assessment for activities that are located within or abutting a critical habitat, or that are adjacent to a critical habitat, and have the potential to significantly impact a critical habitat. The assessment shall determine the extent, function and value of the critical habitat and potential for impacts and mitigation consistent with report requirements in RMC 4-8-120D. In cases where a proposal is not likely to significantly impact the critical habitat and there is sufficient information to determine the effects of a proposal, an applicant may request that this report be waived by the Department Administrator in accordance with subsection D4b of this Section.

3. Bald Eagle Habitat: Bald eagle habitat shall be protected pursuant to the Washington State Bald Eagle Protection Rules (WAC 232-12-292).

4. Native Growth Protection Areas: Based on the required habitat assessment, critical habitat areas and their associated buffers may be required to be placed in a native growth protection area subject to the requirements of subsection E4 of this Section, or dedicated to a conservation organization or land trust, or similarly preserved through a permanent protective mechanism acceptable to the City. (Ord. 5676, 12-3-2012)

5. Alterations Require Mitigation: If alterations to critical habitat/wildlife habitat or buffers are proposed, mitigation shall be required by the City. The applicant shall evaluate alternative methods of developing the property using the following criteria in this order:

a. Avoid any disturbances to the habitat.

b. Minimize any impacts to the habitat.

c. Compensate for any habitat impacts.

6. Mitigation Options: In addition to any performance standards or mitigation required by wetland regulations, additional mitigation may be required based upon the consultant report submitted by the applicant, and/or peer review of the applicant’s consultant report by a qualified professional selected by the City at the applicant’s expense, and/or by information from State or Federal agencies. (Ord. 5676, 12-3-2012)

a. On-Site Mitigation: Mitigation shall be provided on-site, unless on-site mitigation is not scientifically feasible due to physical features of the property. The burden of proof shall be on the applicant to demonstrate that mitigation cannot be provided on-site.

b. Off-Site Mitigation: When mitigation cannot be provided on-site, mitigation shall be provided in the immediate vicinity of the permitted activity on property owned or controlled by the applicant, and identified as such through a recorded document such as an easement or covenant, provided such mitigation is beneficial to the habitat area and associated resources.

c. In-Kind Mitigation: In-kind mitigation shall be provided except when the applicant demonstrates and the City concurs that greater functional and habitat value can be achieved through out-of-kind mitigation. (Ord. 5676, 12-3-2012)

7. Mitigation Plan: Mitigation plans may be required consistent with subsection F8 of this Section. (Ord. 5137, 4-25-2005)

L. STREAMS AND LAKES:

1. Applicability/Lands to Which These Regulations Apply: These stream and lake regulations apply to sites containing all or portions of Class 2 to 4 streams or lakes and/or their buffers as described below. This section does not apply to Class 1 waters which are regulated by RMC 4-3-090, Shoreline Master Program Regulations, or to Class 5 waters which are exempt. All other critical area regulations, including, but not limited to, flood hazard regulations and wetland regulations, do apply to classified streams where applicable.

a. Classification System: The following classification system is hereby adopted for the purposes of regulating streams and lakes in the City. Stream and lake buffer widths are based on the following rating system:

i. Class 1: Class 1 waters are perennial salmonid-bearing waters which are classified by the City and State as Shorelines of the State.

ii. Class 2: Class 2 waters are perennial or intermittent salmonid-bearing waters which meet one or more of the following criteria:

(a) Mapped on Figure Q4, Renton Water Class Map, as Class 2; and/or

(b) Historically and/or currently known to support salmonids, including resident trout, at any stage in the species lifecycle; and/or

(c) Is a water body (e.g., pond, lake) between one half (0.5) acre and twenty (20) acres in size.

iii. Class 3: Class 3 waters are non-salmonid-bearing perennial waters during years of normal rainfall, and/or mapped on Figure Q4, Renton Water Class Map, as Class 3.

iv. Class 4: Class 4 waters are non-salmonid-bearing intermittent waters during years of normal rainfall, and/or mapped on Figure Q4, Renton Water Class Map, as Class 4.

v. Class 5: Class 5 waters are non-regulated non-salmonid-bearing waters which meet one or more of the following criteria:

(a) Flow within an artificially constructed channel where no naturally defined channel had previously existed; and/or

(b) Are a surficially isolated water body less than one-half (0.5) acre (e.g., pond) not meeting the criteria for a wetland as defined in subsection M of this Section.

b. Measurement:

i. Stream/Lake Boundary: The boundary of a stream or lake shall be considered to be its ordinary high water mark (OHWM). The OHWM shall be flagged in the field by a qualified consultant when any study is required pursuant to subsection L of this Section.

ii. Buffer: The boundary of a buffer shall extend beyond the boundaries of the stream or lake to the width applicable to the stream/lake class as noted in Subsection L5 of this Section, Stream/Lake Buffer Width Requirements. Where streams enter or exit pipes, the buffer in this subsection L1b(ii) shall be measured perpendicular to the ordinary high water mark from the end of the pipe along the open channel section of the stream.

Figure 4-3-050L1b(ii). Buffer measurement at pipe opening.

c. Maps and Inventory:

i. Mapped Streams and Lakes: The approximate location and extent of Class 2 to 4 water bodies within the City limits are indicated on a map in subsection Q of this Section, Maps. The map is to be used as a guide to the general location and extent of streams. Specific locations and extents will be determined by the City based upon field review and applicant-funded studies prepared pursuant to subsection L3 of this Section.

ii. Reclassification: Where there is a conflict between the Renton Water Class Map in Subsection Q and the criteria in subsection L1a of this Section, the criteria in subsection L1a of this Section shall govern. The reclassification of a water body to a lower class (i.e., 2 to 3, or 3 to 4, etc.) requires administrator acceptance of a supplemental stream or lake study, followed by a legislative amendment to the map in subsection Q of this Section prior to its effect. The reclassification of a water body to a higher class (i.e., 5 to 4, or 4 to 3, or 3 to 2, etc.) requires either: administrator acceptance of a supplemental stream or lake study, or consultation with the Washington Department of Fish and Wildlife, followed by a legislative amendment to the map in Subsection Q of this Section prior to its effect. (Ord. 5468, 7-13-2009)

iii. Unmapped Streams and Lakes: Streams and lakes which are defined in subsection L1a of this Section, Classification System, but not shown on the Renton Water Class Map in subsection Q of this Section, are presumed to exist in the City and are regulated by all the provisions of this Section. If the water body is unmapped according to the City of Renton’s Water Class Map (refer to subsection Q of this Section), and:

(a) The width of the stream channel averages less than two feet (2') at the ordinary high water mark; or

(b) The stream channel has an average gradient of greater than twenty percent (20%); or

(c) The channel or water body is upstream of an existing, enduring, and complete barrier to salmonid migration, as interpreted in subsection L1c(iv) of this Section, or as shown on the City of Renton’s Salmonid Migration Barrier Map, and the channel or water body contains water only intermittently upstream of the barrier during years of normal rainfall; or

(d) The water body is isolated from any connected stream and/or wetland; or

(e) The water body is less than one-half (0.5) acre in size and connected to a stream meeting the criteria noted in subsections L1c(iii)(a) through (c) of this Section;

Then the water body is considered non-salmonid-bearing and water class would be assessed based upon the non-salmonid-bearing waters criteria in subsections L1a(iii) through (v) of this section. However, if none of the conditions above apply, then the water body is considered Salmonid-Bearing – Class 2. Classification of an unmapped stream or lake requires the Administrator’s determination, followed by a legislative amendment to the map prior to its effect. (Ord. 5468, 7-13-2009)

iv. Salmonid Migration Barriers: For the purposes of classifying or reclassifying water bodies, features determined by the Administrator to be salmonid migration barriers per definition in RMC 4-11-190 shall be mapped. The Administrator shall prepare and update the map as appropriate and maintain a copy in the Planning Customer Service Area. (Ord. 5450, 3-2-2009)

v. Experts or State Agency May Be Required or Consulted: The City may require an applicant to retain an expert or to consult the Washington Department of Fish and Wildlife to assess salmonid-bearing status of the channel in question and prepare a report to the City detailing the facts and conclusion of their analysis.

vi. Criteria to Govern: The actual presence or absence of the stream and lake criteria listed in this subsection L, as determined by qualified professionals, shall govern the treatment of an individual building site or parcel of land requiring compliance with these regulations.

2. Applicability – Activities to Which This Section Applies: This Section applies to all non-exempt activities on sites containing Class 2 to 4 streams or lakes and their associated buffers.

3. Studies Required:

a. When Standard Stream or Lake Study Is Required: The applicant shall be required to conduct a standard stream or lake study per RMC 4-8-120 if a site contains a water body or buffer area or the project area is within one hundred feet (100') of a water body even if the water body is not located on the subject property.

b. When Supplemental Stream or Lake Study is Required: The applicant shall be required to conduct a supplemental stream or lake study per RMC 4-8-120 if a site contains a water body or buffer area and changes to buffer requirements or alterations of the water body or its associated buffer are proposed, either administratively or via a variance request.

c. When Stream or Lake Mitigation Plan is Required: The applicant shall be required to conduct a stream or lake mitigation plan per RMC 4-8-120 if impacts are identified within a supplemental stream or lake study. The approval of the stream or lake mitigation plan by the Administrator shall be based on the criteria located in subsection L3c(ii) of this Section.

i. Timing of Mitigation Plan – Final Submittal and Commencement: When a stream or lake mitigation plan is required, the applicant shall submit a final mitigation plan for the approval of the Administrator prior to the issuance of building or construction permits, whichever comes first. The applicant shall receive written approval of the final mitigation plan prior to commencement of any mitigation activity.

ii. Criteria for Approval of Stream or Lake Mitigation Plan for Alterations of Streams and Lakes or Associated Buffers: In order to approve a stream or lake mitigation plan the Administrator shall find that the plan demonstrates compliance with the following criteria:

(a) Mitigation Location: Mitigation location shall follow the preferences in subsections L3c(ii)(a)(1) to (4) of this Section. Basins and subbasins are indicated in subsection Q of this Section, Maps:

(1) On-Site Mitigation: On-site mitigation is required unless a finding is made that on-site mitigation is not feasible or desirable; (Ord. 5676, 12-3-2012)

(2) Off-Site Mitigation within Same Drainage Subbasin as Subject Site: Off-site mitigation may be allowed when located within the same drainage subbasin as the subject site and if it achieves equal or improved ecological functions over mitigation on the subject site;

(3) Off-Site Mitigation within Same Drainage Basin within City Limits: Off-site mitigation may be allowed when located within the same drainage basin within the Renton City limits if it achieves equal or improved ecological functions within the City over mitigation within the same drainage subbasin as the project;

(4) Off-Site Mitigation within the Same Drainage Basin Outside the City Limits: Off-site mitigation may be allowed when located within the same drainage basin outside the Renton City limits if it achieves equal or improved ecological functions over mitigation within the same drainage basin within the Renton City limits and it meets City goals.

(b) Mitigation Type: Types of mitigation shall follow the preferences in subsections L3c(ii)(b)(1) to (4) of this Section:

(1) Daylighting (returning to open channel) of streams or removal of manmade salmonid migration barriers;

(2) Removal of impervious surfaces in buffer areas and improved biological function of the buffer;

(3) In-stream or in-lake mitigation as part of an approved watershed basin restoration project;

(4) Other mitigation suitable for site and water body conditions that meet all other provisions for a mitigation plan.

In all cases, mitigation shall provide for equivalent or greater biological functions per subsection L3c(ii)(e) of this Section.

(c) Contiguous Corridors: Mitigation sites shall be located to preserve or achieve contiguous riparian or wildlife corridors to minimize the isolating effects of development on habitat areas, so long as mitigation of aquatic habitat is located within the same aquatic ecosystem as the area disturbed; and

(d) Non-Indigenous Species: Wildlife or fish species not indigenous to the region shall not be introduced into a riparian mitigation area unless authorized by a State or Federal permit or approval. Plantings shall be consistent with subsection L6c of this Section; and

(e) Equivalent or Greater Biological Functions: The Administrator shall utilize the report “City of Renton Best Available Science Literature Review and Stream Buffer Recommendations” by AC Kindig & Company and Cedarock Consultants, dated February 27, 2003, unless superseded with a City-adopted study, to determine the existing or potential ecological function of the stream or lake or riparian habitat that is being affected. Mitigation shall address each function affected by the alteration. Mitigation to compensate alterations to stream/lake areas and associated buffers shall achieve equivalent or greater biologic and hydrologic functions and shall include mitigation for adverse impacts upstream or downstream of the development proposal site. No net loss of riparian habitat or water body function shall be demonstrated; and

(f) Minimum Mitigation Plan Performance Standards: See Subsection F8 of this Section.

(g) Additional Conditions of Approval: The Administrator shall condition approvals of activities allowed within or abutting a stream/lake or its buffers, as necessary to minimize or mitigate any potential adverse impacts. Conditions may include, but are not limited to, the following:

(1) Preservation of critically important vegetation and/or habitat features such as snags and downed wood;

(2) Limitation of access to the habitat area, including fencing to deter unauthorized access;

(3) Seasonal restriction of construction activities; and

(4) Establishment of a duration and timetable for periodic review of mitigation activities.

(h) Based on Best Available Science: The applicant shall demonstrate that the mitigation is based on consideration of the best available science as described in WAC 365-195-905; or where there is an absence of valid scientific information, the steps in RMC 4-9-250F are followed.

iii. Performance Surety: The Administrator shall require a performance surety to ensure completion and success of proposed mitigation, per subsection G of this Section and RMC 4-1-230.

iv. Alternative Mitigation: The mitigation requirements set forth in this subsection L3 may be modified at the Administrator’s discretion if the applicant demonstrates that improved habitat functions, on a per function basis, can be obtained in the affected sub-drainage basin as a result of alternative mitigation measures.

d. Studies Waived:

i. Standard Stream or Lake Study: May only be waived by the Administrator when the applicant provides satisfactory evidence that:

(a) A road, building or other barrier exists between the water body and the proposed activity, or

(b) The water body or required buffer area does not intrude on the applicant’s lot, and based on evidence submitted, the proposal will not result in significant adverse impacts to nearby water bodies regulated under this Section; or

(c) Applicable data and analysis appropriate to the proposed project exists and an additional study is not necessary.

ii. Supplemental Stream or Lake Study: May only be waived by the Administrator when:

(a) No alterations or changes to the stream or lake, or its standard buffer are proposed; or

(b) Applicable data and analysis appropriate to the proposed project exists and an additional report is not necessary.

iii. Stream or Lake Mitigation Plan: May only be waived when no impacts have been identified through a supplemental stream or lake study.

e. Period of Validity for Studies Associated with This Section: Studies submitted and reviewed are valid for five (5) years from date of study completion unless the Administrator determines that conditions have changed significantly.

4. General Standards for Class 2 to 4 Waters:

a. Disturbance Prohibited: Streams and lakes and their buffer areas shall be undisturbed, except where the buffer is to be enhanced, or where exemptions allowed in subsection C of this Section are conducted, or where allowed to be altered in accordance with subsections L5, L7 and L8 of this Section. Where water body or buffer disturbance has occurred in accordance with exemption or development permit approval during construction or other activities, revegetation with native vegetation shall be required.

b. No Net Loss: There shall be no net loss of riparian area or shoreline ecological function resulting from any activity or land use occurring within the regulated buffer area.

5. Stream/Lake Buffer Width Requirements:

a. Buffers and Setbacks:

i. Minimum Stream/Lake Buffer Widths: The minimum width of the required buffers shall be based upon the water body class.

(a) Class 2: one hundred feet (100').

(b) Class 3: seventy five feet (75').

(c) Class 4: thirty five feet (35').

ii. Piped or Culverted Streams:

(a) Building structures over a natural stream located in an underground pipe or culvert except as may be granted by a variance in RMC 4-9-250 is prohibited. Transportation or utility crossings or other alterations pursuant to subsection L8 of this Section are allowed. Pavement over a pre-existing piped stream is allowed. Relocation of the piped stream system around structures is allowed. If structure locations are proposed to be changed or the piped stream is being relocated around buildings, a hydrologic and hydraulic analysis of existing piped stream systems will be required for any development project site that contains a piped stream to ensure it is sized to convey the one hundred (100) year runoff level from the total upstream tributary area based on future land use conditions.

(b) No buffers are required along segments of piped or culverted streams. The City shall require easements and setbacks from pipes or culverts consistent with stormwater requirements in RMC 4-6-030 and the adopted drainage manual.

b. Increased Buffer Width:

i. Areas of High Blow-down Potential: Where the stream/lake buffer is in an area of high blow-down potential as identified by a qualified professional, the buffer width may be expanded an additional fifty feet (50') on the windward side. Notifications may be required per subsection F8 of this Section. (Ord. 5676, 12-3-2012)

ii. Buffers Falling Within Protected Slope or Very High Landslide Area: When the required stream/lake buffer falls within a protected slope or very high landslide hazard area or buffer, the stream/lake buffer width shall extend to the boundary of the protected slope or the very high landslide hazard buffer. Notifications may be required per subsection F8 of this Section.

c. Reduction of Buffer Width:

i. Authority: Based upon an applicant’s request, and the acceptance of a supplemental stream or lake study, the Administrator may approve a reduction in the minimum buffer widths where the applicant can demonstrate compliance with subsections L5c(iv)(a), (c), (d), (e) and (f) of this Section and any mitigation requirements as a result of subsection L3c(ii) of this Section; or compliance with subsections L5c(iv)(b), (c), (d), (e), and (f) of this Section and any mitigation requirements as a result of subsection L3c(ii) of this Section.

ii. Minimum Buffer Width Permissible by Administrator: An enhanced buffer shall not be less than the widths specified below for reduced buffers.

(a) Class 2: seventy five feet (75').

(b) Class 3: fifty feet (50').

(c) Class 4: twenty five feet (25').

(d) Sites Separated from Stream or Lake: As determined by the Administrator, for development proposed on sites separated from the stream or lake by pre-existing, intervening, and lawfully created structures, roads, bulkheads/hard structural stabilization, or other substantial existing improvements. For the purposes of this Section, the intervening lots/parcels, roads, bulkheads/hard structural stabilization, or other substantial improvements shall be found to:

(1) Separate the subject upland property from the water body due to their height or width; and

(2) Substantially prevent or impair delivery of most riparian functions from the subject upland property to the water body.

The buffer width established shall reflect the riparian functions that can be delivered to the regulated stream.

Greater buffer width reductions than listed in subsections L5c(ii)(a) through (c) of this Section require review as a variance per subsection N3 of this Section and RMC 4-9-250B. Where a Class 2 or 3 stream is daylighted, greater buffer reductions may be allowed by modification in subsection N2 of this Section.

iii. Procedure: Such determination and evidence shall be included in the application file. Public notification shall be given as follows:

(a) For applications that are not subject to notices of application per chapter 4-8 RMC, notice of the buffer determination shall be given by posting the site and notifying parties of record, if any, in accordance with chapter 4-8 RMC.

(b) For applications that are subject to notices of application, the buffer determination or request for determination shall be included with notice of application. Upon determination, notification of parties of record, if any, shall be made.

iv. Criteria for Approval of Reduced Buffer Width: The following criteria in subsections L5c(iv)(a) and (c) through (f), or criteria (iv)(b) through (f) of this Section shall be met:

(a) Buffer Condition: Either subsection (1) and (3) through (5) shall be met or subsection (2) through (5) shall be met:

(1) The buffer area land is extensively vegetated with native species, including trees and shrubs, and has less than five percent (5%) non-native invasive species cover, and has less than fifteen percent (15%) slopes; or

(2) The buffer can be enhanced with native vegetation and removal of non-native species per criteria in subsection L5c(iv)(c) of this Section, and has less than fifteen percent (15%) slopes; and

(3) The width reduction will not reduce stream or lake functions, including those of anadromous fish or nonfish habitat; and

(4) The width reduction will not degrade riparian habitat; and

(5) No direct or indirect, short-term or long-term, adverse impacts to regulated water bodies, as determined by the City, will result from a regulated activity. The City’s determination shall be based on specific site studies by recognized experts, pursuant to subsection F3 of this section and RMC 4-8-120; or

(b) The proposal includes daylighting of a stream, or removal of legally installed, as determined by the Administrator, salmonid passage barriers; and

(c) The project includes a buffer enhancement plan using native vegetation and substantiates that the enhanced area will be equal to or improve the functional attributes of the buffer; or in the case of existing developed sites where a natural buffer is not possible, the proposal includes on- or off-site riparian/lakeshore or aquatic enhancement proportionate to its project specific or cumulative impact on shoreline ecological functions; and

(d) The proposal will result in, at minimum, no net loss of stream/lake/riparian ecological function; and

(e) The proposal does not result in increased flood hazard risk; and

(f) The proposed buffer standard is based on consideration of the best available science as described in WAC 365-195-905; or where there is an absence of valid scientific information, the steps in RMC 4-9-250F are followed.

d. Averaging of Buffer Width:

i. Authority: Based upon an applicant’s request, and the acceptance of a supplemental stream or lake study, the Administrator may approve buffer width averaging.

ii. Minimum Averaged Buffer Widths: In no instance shall the buffer width be less than:

(a) Class 2: fifty feet (50').

(b) Class 3: thirty seven and one-half feet (37.5').

(c) Class 4: twenty five feet (25').

Greater buffer width reductions than listed in subsections L5(d)(iii)(a) through (c) of this Section require review as a variance per subsection N3 of this Section and RMC 4-9-250B.

iii. Criteria for Approval: Buffer width averaging may be allowed by the Administrator only where the applicant demonstrates all of the following:

(a) The water body and associated riparian area contains variations in ecological sensitivity or there are existing physical improvements in or near the water body and associated riparian area; and

(b) Buffer width averaging will result in no net loss of stream/lake/riparian ecological function; and

(c) The total area contained within the buffer after averaging is no less than that contained within the required standard buffer width prior to averaging; and

(d) The proposed buffer standard is based on consideration of the best available science as described in WAC 365-195-905; or where there is an absence of valid scientific information, the steps in RMC 4-9-250F are followed.

iv. Buffer Enhancement May be Required: Where the buffer width is reduced by averaging per this subsection, buffer enhancement shall be required where appropriate to site conditions, habitat sensitivity, and proposed land development characteristics.

v. Notification: Notification may be required consistent with subsection F8 of this Section.

6. Stream or Lake Buffer Use Restrictions and Maintenance: Any activity or proposal subject to this subsection L shall comply with the following standards within required buffer areas:

a. Preservation of Native Vegetation: Existing native vegetation shall be preserved to the extent possible, preferably in consolidated areas.

b. Revegetation Required: Where water body buffer disturbance has occurred in accordance with exemption or development permit approval or other activities, revegetation with native vegetation shall be required.

c. Use of Native Species: When revegetation is required, approved native species, or other appropriate species naturalized to the Puget Sound region shall be used. A variety of species shall be used which serve as food or shelter from climatic extremes and predators, and as structure and cover for reproduction and rearing of young. (Ord. 5676, 12-3-2012)

d. Removal of Noxious Species: When required as a condition of approval, noxious or undesirable species of plants shall be removed or controlled so as to not compete with native vegetation.

e. Impervious Surface Restrictions: Where impervious surfaces exist in buffer areas, such impervious surfaces shall not be increased or expanded within the buffer area. The extent of impervious surfaces within the buffer area may only be rearranged if the reconfiguration of impervious surfaces and restoration of prior surfaced areas is part of an enhancement proposal that improves ecological function of the area protected by the buffer.

7. Criteria for Permit Approval – Class 2 to 4: Permit approval for projects on or near regulated water bodies shall be granted only if the approval is consistent with the provisions of this subsection L, and complies with the following:

a. Creation of Native Growth Protection Areas Required: As a condition of any approval for any development permit issued pursuant to this Section, the property owner shall be required to create a native growth protection area containing the stream/lake area and associated buffers based upon field investigations performed pursuant to subsection E4 of this Section; and

b. At least one of the following conditions must apply:

i. A proposed action meets the standard provisions of this Section and results in no net loss of regulated riparian area or shoreline ecological function in the drainage basin where the site is located; or

ii. A proposed action meets alternative administrative standards pursuant to this Section and the proposed activity results in no net loss of regulated riparian area or shoreline ecological function in the drainage basin where the site is located; or

iii. A variance process is successfully completed and the proposed activity results in no net loss of regulated riparian area or shoreline ecological function in the drainage basin where the site is located. (Ord. 5676, 12-3-2012)

8. Alterations Within Streams and Lakes or Associated Buffers.

a. Transportation Crossings:

i. Criteria for Administrative Approval of Transportation Crossings in Stream/Lake or Buffer Areas: Construction of vehicular or non-vehicular transportation crossings may be permitted in accordance with an approved supplemental stream/lake study subject to the following criteria:

(a) The proposed route is determined to have the least impact on the environment, while meeting City Comprehensive Plan Transportation Element requirements and standards in RMC 4-6-060; and

(b) The crossing minimizes interruption of downstream movement of wood and gravel; and

(c) Transportation facilities in buffer areas shall not run parallel to the water body; and

(d) Crossings occur as near to perpendicular with the water body as possible; and

(e) Crossings are designed according to the Washington Department of Fish and Wildlife Fish Passage Design at Road Culverts, 1999, and the National Marine Fisheries Service Guidelines for Salmonid Passage at Stream Crossings, 2000, as may be updated, or equivalent manuals as determined by the Administrator; and (Ord. 5676, 12-3-2012)

(f) Seasonal work windows are determined and made a condition of approval; and

(g) Mitigation criteria of subsection L3c(ii) of this Section are met.

b. Alterations of Streams and Lakes or Associated Buffers – Utilities:

i. Criteria for Administrative Approval of Utilities in Stream/Lake or Buffer: New utility lines and facilities may be permitted to cross water bodies in accordance with an approved supplemental stream/lake study, if they comply with the following criteria:

(a) Fish and wildlife habitat areas shall be avoided to the maximum extent possible; and

(b) The utility is designed consistent with one or more of the following methods:

(1) Installation shall be accomplished by boring beneath the scour depth and hyporheic zone of the water body and channel migration zone; or

(2) The utilities shall cross at an angle greater than sixty (60) degrees to the centerline of the channel in streams or perpendicular to the channel centerline; or

(3) Crossings shall be contained within the footprint of an existing road or utility crossing; and

(c) New utility routes shall avoid paralleling the stream or following a down-valley course near the channel; and

(d) The utility installation shall not increase or decrease the natural rate of shore migration or channel migration; and

(e) Seasonal work windows are determined and made a condition of approval; and

(f) Mitigation criteria of subsection L3c(ii) of this Section are met.

c. Alterations of Streams and Lakes or Associated Buffers – In-Water Structures and In-Water Work:

i. Administrative Approval of In-Water Structures or In-Water Work: In accordance with an approved supplemental stream or lake study, in-water structures or work may be permitted, subject to the following: In-stream structures, such as, but not limited to, high flow bypasses, sediment ponds, in-stream ponds, retention and detention facilities, tide gates, dams, and weirs, shall be allowed as part of an approved watershed basin restoration project approved by the City of Renton, and in accordance with mitigation criteria of subsection L3c(ii) of this Section. The applicant will obtain and comply with State or Federal permits and requirements.

d. Alterations of Streams and Lakes or Associated Buffers – Dredging.

i. Administrative Approval of Dredging: Dredging may be permitted only when:

(a) Dredging is necessary for flood hazard reduction purposes, if a definite flood hazard would exist unless dredging were permitted; or

(b) Dredging is necessary to correct problems of material distribution and water quality, when such problems are adversely affecting aquatic life; or

(c) Dredging is associated with a stream habitat enhancement or creation project not otherwise exempt in subsection C of this Section; or

(d) Dredging is necessary to protect public facilities; or

(e) Dredging is required as a maintenance and operation condition of a federally funded flood hazard reduction project or a hazard mitigation project; and

(f) Applicable mitigation criteria of subsection L3c(ii) of this Section are met.

e. Alterations of Streams and Lakes or Associated Buffers – Stream Relocation:

i. Administrative Approval of Stream Relocation: Stream relocation may be allowed when analyzed in an accepted supplemental stream or lake assessment, and when the following criteria and conditions are met:

(a) Criteria: Stream relocation may only be permitted if associated with:

(1) A public flood hazard reduction/habitat enhancement project approved by appropriate State and/or Federal agencies; or

(2) Expansion of public road or other public facility improvements where no feasible alternative exists; or

(3) A public or private proposal restoring a water body and resulting in a net benefit to on- or off-site habitat and species.

(b) Additional Conditions: The following conditions also apply to any stream relocation proposal meeting one or more of the above criteria:

(1) Buffer widths shall be based upon the new stream location; provided, that the buffer widths may be reduced or averaged if meeting criteria of subsection L5c or L5d of this Section or subsection L8e(i)(b)(2) of this Section. Where minimum required buffer widths are not feasible for stream relocation proposals that are the result of activities pursuant to criteria in subsections L8e(i)(a)(1) and (2) of this Section, other equivalent on- or off-site compensation to achieve no-net-loss of riparian function is provided;

(2) When Class 4 streams are proposed for relocation due to expansions of public roads or other public facility improvements per subsection L8e(i)(a)(2) of this Section, the buffer area between the facility and the relocated stream shall not be less than the width prior to the relocation. The provided buffer between the facility and the relocated stream shall be enhanced or improved to provide appropriate function given the class and condition of the stream; or if there is no buffer currently, other equivalent on- or off-site compensation to achieve no net loss of riparian function is provided.

(3) Applicable mitigation criteria of subsection L3c(ii) of this Section must be met.

(4) Proper notifications and records must be made of stream relocations, per subsection D3b of this Section, Information to be Obtained and Maintained, and subsection D3c of this Section, Alterations of Watercourses, in cases where the stream/lake is subject to flood hazard regulations of this Section, as well as subsection F8 of this Section if neighboring properties are impacted.

f. Alterations – Single Family Home – Existing Legal Lot: If criteria to reduce or average a buffer cannot be met, construction, reconstruction, additions, and associated accessory structures of a single family home on an existing legal lot may be allowed to intrude into a buffer pursuant to a variance as stated in RMC 4-9-250B1.

g. Alterations – Other: Proposed alterations of a stream or lake or associated buffer not addressed by subsections L8a to L8f of this Section require a variance pursuant to RMC 4-9-250B in order to be conducted.

h. When Variance Is Required: If the proposed alteration applicable to Subsections L8a to L8g of this Section does not meet the above criteria, it shall require a variance per subsection N3 of this Section and RMC 4-9-250B in order to be conducted.

9. Incentives for Restoration of Streams Located in an Underground Pipe or Culvert: Daylighting of culverted watercourses should be encouraged and allowed with the following incentives:

a. Modified Standards:

i. Residential Zones: Reduced setbacks, lot width and lot depth standards of chapter 4-2 RMC may be approved without requirement of a variance for lots that abut the daylighted watercourse to accommodate the same number of lots as if the watercourse were not daylighted. (Ord. 5676, 12-3-2012)

ii. Mixed Use, Commercial, and Industrial Zones:

(a) Where greater lot coverage allowances are provided for structured parking in chapter 4-2 RMC, lot coverage may be increased to the limit allowed for structured parking if instead a stream is daylighted. The increase in impervious surface allowed shall be equal to the area of stream restoration.

(b) Density bonuses may be allowed pursuant to RMC 4-9-065 where specified.

b. Standard buffers may be reduced per subsection L5c of this Section. If reduced buffers in subsection L5c of this Section along with other development standards of the zone would not allow the same development level as without the watercourse daylighting, a modification may be requested as in subsection N of this Section.

c. When designed consistent with the City’s flood regulations in subsection I6 of this Section, portions of the daylighted stream/created buffer may be considered part of compensatory storage in flood hazard areas.

d. Stream relocation is permitted subject to subsection L8 of this Section. (Ord. 5137, 4-25-2005)

M. WETLANDS:

1. Applicability: The wetland regulations apply to sites containing or abutting wetlands as described below. Category 3 wetlands, less than two thousand two hundred (2,200) square feet in area, are exempt from these regulations if they meet exemption criteria in subsection C of this Section.

a. Classification System: The following classification system is hereby adopted for the purposes of regulating wetlands in the City. Wetlands buffer widths, replacement ratios and avoidance criteria shall be based on the following rating system:

i. Category 1: Category 1 wetlands are wetlands which meet one or more of the following criteria:

(a) The presence of species listed by Federal or State government as endangered or threatened, or the presence of essential habitat for those species; and/or

(b) Wetlands having forty percent (40%) to sixty percent (60%) permanent open water (in dispersed patches or otherwise) with two (2) or more vegetation classes; and/or

(c) Wetlands equal to or greater than ten (10) acres in size and having three (3) or more vegetation classes, one of which is open water; and/or

(d) The presence of plant associations of infrequent occurrence; or at the geographic limits of their occurrence; and/or

ii. Category 2: Category 2 wetlands are wetlands which meet one or more of the following criteria:

(a) Wetlands that are not Category 1 or 3 wetlands; and/or

(b) Wetlands that have heron rookeries or osprey nests, but are not Category 1 wetlands; and/or

(c) Wetlands of any size located at the headwaters of a watercourse, i.e., a wetland with a perennial or seasonal outflow channel, but with no defined influent channel, but are not Category 1 wetlands; and/or

(d) Wetlands having minimum existing evidence of human-related physical alteration such as diking, ditching or channelization; and/or

iii. Category 3: Category 3 wetlands are wetlands which meet one or more of the following criteria:

(a) Wetlands that are severely disturbed. Severely disturbed wetlands are wetlands which meet the following criteria:

(1) Are characterized by hydrologic isolation, human-related hydrologic alterations such as diking, ditching, channelization and/or outlet modification; and

(2) Have soils alterations such as the presence of fill, soil removal and/or compaction of soils; and

(3) May have altered vegetation.

(b) Wetlands that are newly emerging. Newly emerging wetlands are:

(1) Wetlands occurring on top of fill materials; and

(2) Characterized by emergent vegetation, low plant species richness and used minimally by wildlife. These wetlands are generally found in the areas such as the Green River Valley and Black River Drainage Basin.

(c) All other wetlands not classified as Category 1 or 2 such as smaller, high quality wetlands.

b. Maps and Inventory:

i. The approximate location and extent of wetlands in the City is displayed in subsection Q of this Section, Maps. The map is to be used as a guide to the general location and extent of wetlands.

ii. Wetlands which are defined in subsection M1a of this Section, Classification System, but not shown on the Renton Wetlands Map Inventory, are presumed to exist in the City and are also protected under all the provisions of this Section.

iii. The actual presence or absence of the wetland criteria listed above, as determined by qualified professionals, shall govern the treatment of an individual building site or parcel of land requiring compliance with these regulations.

c. Delineation of Wetland Edge: For the purpose of regulation, the wetland edge should be delineated pursuant to subsection M4 of this Section.

d. Regulated and Nonregulated Wetlands: Refer to subsection M1a and M1e of this Section for applicability thresholds for regulatory and nonregulatory wetlands.

e. Performance Standards: In addition to general standards of subsection E of this Section, the following performance standards apply to all regulated wetlands.

i. Regulated and Nonregulated Wetlands – General: Wetlands created or restored as a part of a mitigation project are regulated wetlands. Regulated wetlands do not include those artificial wetlands intentionally created from nonwetland sites for purposes other than wetland mitigation, including, but not limited to, irrigation and drainage ditches, grass-lined swales, canals, detention facilities, wastewater treatment facilities, farm pond, and landscape amenities, or those wetlands created after July 1, 1990, that were unintentionally created as a result of the construction of a road, street, or highway. The Department Administrator shall determine that a wetland is not regulated on the basis of photographs, statements, and other evidence.

ii. Nonregulated Category 3 Wetlands: Based upon an applicant request, the Department Administrator may determine that Category 3 wetlands are not considered regulated wetlands, if the applicant demonstrates the following criteria are met:

(a) The wetland formed on top of fill legally placed on a property; and

(b) The wetland hydrology is solely provided by the compaction of the soil and fill material; and

(c) The U.S. Army Corps of Engineers has determined that they will not take jurisdiction over the wetland.

2. General Standards for Permit Approval: Permit approval for projects involving regulated wetlands or wetland buffers shall be granted only if the approval is consistent with the provisions of this Section. Additionally, approvals shall only be granted if:

a. A proposed action avoids adverse impacts to regulated wetlands or their buffers or takes affirmative and appropriate measures to minimize and compensate for unavoidable impacts; and

b. The proposed activity results in no net loss of regulated wetland area, value, or function in the drainage basin where the wetland is located; or

c. A variance process is successfully completed to determine conditions for permitting of activity requested including measures to reduce impacts as appropriate. (Ord. 5676, 12-3-2012)

3. Study Required:

a. When Study Is Required: Wetland assessments are required as follows:

i. Wetland Classification: The applicant shall be required to conduct a study to determine the classification of the wetland if the subject property or project area is within one hundred feet (100') of a wetland even if the wetland is not located on the subject property but it is determined that alterations of the subject property are likely to impact the wetland in question or its buffer. If there is a potential Category 1 or 2 wetland within three hundred feet (300') of a proposal, the City may require an applicant to conduct a study even if the wetland is not located on the subject property but it is determined that alterations of the subject property are likely to impact the wetland in question or its buffer.

ii. Wetland Delineation: A wetland delineation is required for any portion of a wetland on the subject property that will be impacted by the permitted activities.

b. Study Waived: The wetland assessment shall be waived by the Department Administrator when the applicant provides satisfactory evidence that a road, building or other barrier exists between the wetland and the proposed activity, or when the buffer area needed or required will not intrude on the applicant’s lot, or when applicable data and analysis appropriate to the project proposed exists and an additional report is not necessary.

4. Delineation of Regulatory Edge of Wetlands:

a. Methodology: For the purpose of regulation, the exact location of the wetland edge shall be determined by the wetlands specialist hired at the expense of the applicant through the performance of a field investigation using the procedures provided in the following manual: Washington State Wetlands Identification and Delineation Manual, Washington State Department of Ecology, March 1997, Ecology Publication No. 96-94.

b. Delineations – Open Water: Where wetlands are contiguous with areas of open freshwater, streams, or rivers, the delineation shall be consistent with the Washington State Wetlands Rating System: Western Washington, Second Edition, Washington State Department of Ecology, August 1993, Publication No. 93-74, Appendix 5, or another accepted Federal or State methodology, subject to City review.

c. Adjustments to Delineation by City: Where the applicant has provided a delineation of the wetland edge, the City shall review and may render adjustments to the edge delineation. In the event the adjusted edge delineation is contested by the applicant, the City shall, at the applicant’s expense, obtain the services of an additional qualified wetlands specialist to review the original study and render a final delineation.

d. Period of Validity for Wetland Delineation:

i. Within City Limits: A final wetland delineation, for properties within the city limits at the time the delineation was prepared, is valid for five (5) years, unless the Administrator determines that conditions have changed.

ii. Outside City Limits: The period of validity of wetland delineations for properties, which were unincorporated at the time of the delineation, will be determined by the Administrator. Following a review of a wetland delineation prepared for an unincorporated property, since annexed into the City, the Administrator may require adjustments be made to the study or a new study prepared, per subsection M4 of this Section, Delineation of Regulatory Edge of Wetlands.

5. Determination of Wetland Classification: Wetland studies shall determine the appropriate wetland classification according to subsection M1 of this Section, Wetlands. The City may accept a dual wetland classification for a wetland exhibiting a combination of Category 1 and 2 features or a combination of Category 1 and 3 features. The City will not accept a dual rating for a Category 2 wetland, such as a combined Category 2 and 3 rating. Dual ratings for a Category 1 wetland shall be consistent with the Washington State Wetlands Rating System: Western Washington, Second Edition, Washington State Department of Ecology, August 1993, Publication No. 93-74 or as thereafter amended or updated.

6. Wetland Buffers:

a. Buffers Required:

i. Wetland buffer zones shall be required of all proposed regulated activities abutting regulated wetlands.

ii. Any wetland created, restored, or enhanced in conjunction with creation or restoration as compensation for approved wetland alterations shall include the standard buffer required for the class of the wetland being replaced.

iii. All required wetland buffer zones shall be retained in their natural condition. Category 3 wetland buffers of twenty five feet (25') require the buffers be fully vegetated with native species or restored; otherwise increased buffer widths to protect functions and values may be required.

iv. Where buffer disturbance has occurred during construction or other activities, revegetation with native vegetation may be required.

b. Measurement of Buffers: All buffers shall be measured from the wetland boundary as surveyed in the field pursuant to the requirements of subsection M4a of this Section, Methodology.

c. Standard Buffer Zone Widths:

i. The width of the required wetland buffer zone shall be determined according to the wetland category. The buffer zone required for all regulated wetlands is determined by the classification of the wetland. If standard buffer widths cannot be met, and buffer reductions per subsection M6e of this Section and buffer averaging per subsection M6f of this Section cannot be accomplished, a variance to buffer requirements may be requested per subsection N of this Section, Alternates, Modifications and Variances, and RMC 4-9-250B, Variance Procedures. If the criteria in subsection M6d of this Section are met, standard buffers may be increased.

Wetland Category	Standard Buffer
Category 1	100 feet
Category 2	50 feet
Category 3	25 feet

ii. To protect the buffer functions, permits shall be conditioned as appropriate to the nature of the development. Conditions of approval may include, but are not limited to, the following:

(a) Fencing pursuant to subsection E4e of this Section, plant materials, and signage pursuant to subsection E4f of this Section, to limit pet and human disturbance;

(b) Directing lights from buildings or parking areas, or noise-generating activities, away from the wetland;

(c) Implementing water quality treatment measures required in RMC 4-6-030, Drainage (Surface Water) Standards;

(d) Avoidance of buffer disturbance and retention of the buffer in a natural condition consistent with subsection M6a of this Section. (Ord. 5676, 12-3-2012)

d. Increased Wetland Buffer Zone Width: Each applicant shall document in required wetland assessments whether the criteria in subsections M6d(i) through (iv) of this Section are or are not met and increased wetland buffers are warranted. Based on the applicant’s report or third party review, increased standard buffer zone widths may be required in unique cases, i.e., endangered species, very fragile areas, when a larger buffer is necessary to protect wetlands functions and values. Such determination shall be attached as a condition of project approval. Analysis shall be prepared as directed in subsection M6d(v) of this section, and notification shall be given pursuant to criteria in subsection M6d(vi) of this Section.

i. The wetland is used by species listed by the Federal or the State government as threatened, endangered and sensitive species and State-listed priority species, essential habitat for those species or has unusual nesting or resting sites such as heron rookeries or raptor nesting trees or evidence thereof; or

ii. The subject property, or nearby lands to which the subject property drains in route to a wetland, are susceptible to severe erosion, and erosion control measures will not effectively prevent adverse wetland impacts; or

iii. The subject property or nearby lands to which the subject property drains in route to a wetland have minimal vegetative cover or slopes greater than fifteen percent (15%) and conditions cannot be restored to prevent adverse wetland impacts; or

iv. Wetland-dependent wildlife species are observed to be present in the wetland, and may require larger buffers based upon the evaluation in subsection M6d(v) of this Section; and

v. For proposals meeting any of the criteria in subsections M6d(i) to (iv) of this Section, buffers are established using a site specific evaluation and documentation of buffer adequacy based upon The Science of Wetland Buffers and Its Implications for the Management of Wetlands, McMillan 2000, Wetlands in Washington State Volume 2: Guidance for Protecting and Managing Wetlands, Appendix 8C (Hruby, et al., 2005), or similar approaches; and

vi. Notification is given consistent with subsection F8 of this Section. (Ord. 5676, 12-3-2012)

e. Reduction of Buffer Width: Based upon an applicant’s request, the Administrator may approve a reduction in the standard wetland buffer zone widths on a case-by-case basis for Class 1 and 2 wetlands where the applicant can demonstrate compliance with subsections M6e(i) and (iii) or (ii) and (iii) of this Section. Such determination and evidence shall be included in the application file and public notification shall be given in accordance with M6e(iv) of this Section. Conditions may be applied in accordance with subsection M6e(v) of this Section.

i. The buffer area land is extensively vegetated and has less than fifteen percent (15%) slopes and no direct or indirect, short-term or long-term, adverse impacts to regulated wetlands, as determined by the City, will result from a regulated activity. The City’s determination shall be based on specific site studies by recognized experts. The City may require long-term monitoring of the project and subsequent corrective actions if adverse impacts to regulated wetlands are discovered; or

ii. The project includes a buffer enhancement plan using native vegetation and substantiates that the enhanced buffer will be equal to or improve the functional attributes of the buffer. An enhanced buffer shall not result in greater than a twenty five percent (25%) reduction in the buffer width. Greater buffer width reductions require review as a variance per subsection N3 of this Section.

iii. The proposal shall rely upon a site specific evaluation and documentation of buffer adequacy based upon The Science of Wetland Buffers and Its Implications for the Management of Wetlands, McMillan 2000, or similar approaches. The proposed buffer standard is based on consideration of the best available science as described in WAC 365-195-905; or where there is an absence of valid scientific information, the steps in RMC 4-9-250F are followed.

iv. Public notification of the buffer reduction determination shall be given as follows:

(a) For applications that are not subject to notices of application per chapter 4-8 RMC, notice of the buffer determination shall be given by posting the site and notifying parties of record, if any, in accordance with chapter 4-8 RMC.

(b) For applications that are subject to notices of application, the buffer determination or request for determination shall be included with notice of application. Upon determination, notification of parties of record, if any, shall be made.

v. Conditions of approval equivalent or greater than those identified in subsection M6c(ii) of this Section shall be applied to ensure that the reduced buffer width protects the functions and values of the associated wetlands. (Ord. 5676, 12-3-2012)

f. Averaging of Buffer Width: Standard wetland buffer zones may be modified by averaging buffer widths. Upon applicant request, wetland buffer width averaging may be allowed by the Department Administrator only where the applicant demonstrates all of the following:

i. That the wetland contains variations in ecological sensitivity or there are existing physical improvements in or near the wetland and buffer; and

ii. That width averaging will not adversely impact the wetland function and values; and

iii. That the total area contained within the wetland buffer after averaging is no less than that contained within the required standard buffer prior to averaging; and

iv. A site specific evaluation and documentation of buffer adequacy based upon The Science of Wetland Buffers and Its Implications for the Management of Wetlands, McMillan 2000, or similar approaches have been conducted. The proposed buffer standard is based on consideration of the best available science as described in WAC 365-195-905; or where there is an absence of valid scientific information, the steps in RMC 4-9-250F are followed.

v. In no instance shall the buffer width be reduced by more than fifty percent (50%) of the standard buffer or be less than twenty five feet (25') wide. Greater buffer width reductions require review as a variance per subsection N3 of this Section and RMC 4-9-250B; and

vi. Buffer enhancement in the areas where the buffer is reduced shall be required on a case-by-case basis where appropriate to site conditions, wetland sensitivity, and proposed land development characteristics.

vii. Notification may be required pursuant to subsection F8 of this Section.

7. Wetlands – Native Growth Protection Areas: As a condition of any approval issued pursuant to this Section for any development permit, the property owner shall be required to create a separate native growth protection area containing the areas determined to be wetland and/or wetland buffer in field investigations performed pursuant to subsection M4 of this Section, Delineation of Regulatory Edge of Wetlands, and subsection M5 of this Section, Determination of Wetland Classification. Native growth protection areas shall be established pursuant to subsection E4 of this Section.

8. Wetland Changes – Alternative Methods of Development: If wetland changes are proposed for a non-exempt activity, the applicant shall evaluate alternative methods of developing the property using the following criteria in this order and provide reasons why a less intrusive method of development is not feasible. In determining whether to grant permit approval per subsection M2 of this Section, General Standards for Permit Approval, a determination shall be made as to whether the feasibility of less intrusive methods of development have been adequately evaluated and that less intrusive methods of development are not feasible. (Ord. 5676, 12-3-2012)

a. Avoid any disturbances to the wetland or buffer;

b. Minimize any wetland or buffer impacts;

c. Restore any wetlands or buffer impacted or lost temporarily; and

d. Compensate for any permanent wetland or buffer impacts by one of the following methods:

i. Restoring a former wetland and provide buffers at a site once exhibiting wetland characteristics to compensate for wetlands lost;

ii. Creating new wetlands and buffers for those lost; and

iii. In addition to restoring or creating a wetland, enhancing an existing degraded wetland to compensate for lost functions and values.

9. Compensating for Wetlands Impacts:

a. Goal: The overall goal of any compensatory project shall be no net loss of wetland function and acreage and to strive for a net resource gain in wetlands over present conditions. The concept of “no net loss” means to create, restore and/or enhance a wetland so that there is no reduction to total wetland acreage and/or function.

b. Plan Requirements: The applicant shall develop a plan that provides for land acquisition, construction, maintenance and monitoring of replacement wetlands that recreate as nearly as possible the wetland being replaced in terms of acreage, function, geographic location and setting, and that are equal to or larger than the original wetlands.

c. Plan Performance Standards: Compensatory mitigation shall follow an approved mitigation plan pursuant to subsections M8 to M10 of this Section and shall meet the minimum performance standards in subsection F8 of this Section.

d. Acceptable Mitigation – Permanent Wetland Impacts: Any person who alters regulated wetlands shall restore or create equivalent areas or greater areas of wetlands than those altered in order to compensate for wetland losses. Enhancement of wetlands may be provided as mitigation if it is conducted in conjunction with mitigation proposed to create or restore a wetland in order to maintain “no net loss” of wetland acreage. Subsections M10 through M12 provide further detail on wetland restoration, creation, and enhancement.

e. Restoration, Creation, or Combined Enhancement Required – Compensation for Permanent Wetland Impacts: As a condition of any permit allowing alteration of wetlands and/or wetland buffers, or as an enforcement action, the City shall require that the applicant engage in the restoration or creation of wetlands and their buffers (or funding of these activities) in order to offset the impacts resulting from the applicant’s or violator’s actions. Enhancement in conjunction with restoration or creation may be allowed in order to offset the impacts resulting from an applicant’s actions. Enhancement is not allowed as compensation for a violator’s actions.

f. Compensating for Temporary Wetland Impacts: Where wetland disturbance has occurred during construction or other activities, see subsection C5f(ii) of this Section.

g. Mitigation Bank Agreement – Glacier Park Company: Pursuant to the Wetland Mitigation Bank Agreement between the City and the Glacier Park Company, King County recording number 9206241805, wetland alteration and wetland mitigation shall be conducted in accordance with the agreement.

10. Wetland Compensation – Restoration, Creation, and Enhancement: The applicant may propose a mitigation approach that includes restoration or creation solely or combines restoration or creation with enhancement. The City may require one mitigation approach in favor of another if it is determined that:

a. There is a greater probability of success in ensuring no net loss of wetlands acreage, functions, and values; and

b. The mitigation approach can be accomplished on-site rather than off-site.

11. Wetlands Creation and Restoration:

a. Creation or Restoration Proposals: Any applicant proposing to alter wetlands may propose to restore wetlands or create new wetlands, with priority first for on-site restoration or creation and then second, within the drainage basin, in order to compensate for wetland losses. Restoration activities must include restoring lost hydrologic, water quality and biologic functions.

b. Compliance with Goals: Applicants proposing to restore or create wetlands shall identify how the restoration or creation plan conforms to the purposes and requirements of this Section and established regional goals of no net loss of wetlands.

c. Category: Where feasible, created or restored wetlands shall be a higher category than the altered wetland. In no cases shall they be lower, except as follows: For impacts to Category 1 shrub-scrub and emergent wetlands, if it is infeasible to create or restore a site to become a Category 1 wetland, the Administrator may allow for creation/restoration of high quality Category 2 wetlands at one hundred fifty percent (150%) of the normally required creation/replacement ratios of Category 1 shrub-scrub or emergent wetlands, within the basin.

d. Design Criteria: Requirements for wetland restoration or creation as compensation areas shall be determined according to the function, acreage, type and location of the wetland being replaced. Compensation requirements should also consider time factors, the ability of the project to be self-sustaining and the projected success based on similar projects. Wetland functions and values shall be calculated using the best professional judgment of a qualified wetland ecologist using the best available techniques. Multiple or cooperative compensation projects may be proposed for one project in order to best achieve the goal of no net loss. Restoration or creation must be within the same drainage basin.

e. Acreage Replacement Ratio: The ratios listed in subsection M11e(i) of this Section, Ratios for Wetlands Creation or Restoration, apply to all Category 1, 2, or 3 wetlands for restoration or creation which is in-kind, on- or off-site, timed prior to alteration, and has a high probability of success. The required ratio must be based on the wetland category and type that require replacement. Ratios are determined by the probability of recreating successfully the wetland and the inability of guarantees of functionality, longevity, and duplication of type and/or functions.

i. RATIOS FOR WETLANDS CREATION OR RESTORATION:
Wetland Category	Vegetation Type	Creation/Restoration Ratio
Category 1	Forested Scrub-shrub Emergent	6 times the area altered. 3 times the area altered. 2 times the area altered.
Category 2	Forested Scrub-shrub Emergent	3 times the area altered. 2 times the area altered. 1.5 times the area altered.
Category 3	Forested Scrub-shrub Emergent	1.5 times the area altered. 1.5 times the area altered. 1.5 times the area altered.

f. Increased Creation/Restoration/Replacement Ratios: Ratios may be increased under the following circumstances: uncertainty as to the probable success of the proposed restoration or creation; significant period of time between destruction and replication of wetland functions; projected losses in functional value; or off-site compensation. The requirement for an increased replacement ratio will be determined through SEPA review, except in the case of remedial actions resulting from illegal alterations where the Administrator or Environmental Review Committee may require increased wetland replacement ratios. (Ord. 5676, 12-3-2012)

g. Decreased Creation/Restoration/Replacement Ratios:

i. Category 1: Ratios for Category 1 forested and scrub-shrub wetlands may be decreased to 2.0 times the area altered, and to 1.5 times the area altered for emergent wetlands, provided the applicant has successfully replaced the wetland prior to its filling and has shown that the replacement is successfully established for five (5) years.

ii. Category 2: Ratios for Category 2 forested and scrub-shrub wetlands may be decreased to 1.5 times the area altered provided the applicant has successfully replaced the wetland prior to its filling and has shown that the replacement is successfully established for two (2) years. Ratios for Category 2 emergent wetlands may be reduced to 1.25 times the area altered provided the applicant has successfully replaced the wetland prior to its filling and has shown that the replacement is successfully established for two (2) years.

iii. Category 3:

(a) Ratios for Category 3 emergent wetlands may be decreased to 1.0 times the area altered provided the applicant has successfully replaced the wetland prior to its filling and has shown that the replacement is successfully established for twelve (12) months. Ratios for Category 3 scrub-shrub and forested wetlands may be reduced to 1.25 times the area altered provided the applicant has successfully replaced the wetland prior to its filling and has shown that the replacement is successfully established for two (2) years.

(b) If the applicant can aggregate two (2) or more Category 3 wetlands, each less than ten thousand (10,000) square feet, into one wetland, the replacement ratio shall be reduced to 1:1. If the combined wetland would be rated as a Category 2 wetland as a result of the combination, the buffer requirement may be reduced to twenty five feet (25') minimum provided the buffer is enhanced. (Ord. 5676, 12-3-2012)

h. Category 3 Replacement Option: The applicant, at his/her expense, may select to use accepted Federal or State methods to establish the functions and values for the Category 3 wetland being replaced in lieu of replacement by acreage only. A third party review, funded by the applicant, and hired and managed by the City, shall review and verify the reports. Dependent upon the results of the functions and values evaluation, a Category 3 wetland may be replaced by assuring that all the functions and values are replaced in another location, within the same basin.

i. Minimum Restoration/Creation Ratio: Unless allowed by subsection M11g of this Section, restoration or creation ratios may only be reduced by modification or variance pursuant to subsection N of this Section, Alternates, Modifications and Variances, and RMC 4-9-250B, Variance Procedures, and RMC 4-9-250D, Modification Procedures. In order to maintain no net loss of wetland acreage, in no case shall the restoration or creation ratio be less than 1:1. This minimum ratio may not be modified through the modification or variance process.

12. Wetland Enhancement:

a. Enhancement Proposals – Combined with Restoration and Creation: Any applicant proposing to alter wetlands may propose to enhance an existing degraded wetland, in conjunction with restoration or creation of a wetland in order to compensate for wetland losses. Wetland enhancement shall not be allowed as compensation if it is not accomplished in conjunction with a proposal to restore or create a wetland.

b. Evaluation Criteria: A wetland enhancement compensation project may be approved; provided, that enhancement for one function will not degrade another function unless the enhancement would provide a higher functioning wetland with greater or multiple environmental benefits. For example, an enhancement may degrade habitat for one wildlife species but overall it may result in a wetland that provides higher function to a wider variety of wildlife species. Wetland function assessment shall be conducted in conformance with accepted Federal or State methodologies. (Ord. 5676, 12-3-2012)

c. Wetlands Chosen for Enhancement: An applicant proposing to alter wetlands may propose to enhance an existing Category 2 or 3 wetland. Existing Category 1 wetlands shall not be enhanced to compensate for wetland alteration unless the wetland selected for enhancement is a Category 1 wetland only by virtue of its acreage and three (3) vegetation classes, where the existing vegetation is characterized partly or wholly by invasive wetland species.

d. Mitigation Ratios: Wetland alterations shall be created, restored and enhanced using the formulas in subsection M12d(i), Ratios for Wetland Restoration or Creation plus Enhancement. The following is an example of use of the formulas below:

If one acre of Category 2, forested wetland, were proposed to be removed, the creation/replacement ratio (subsection M11e(i) of this Section) requires that three (3) acres of forested Category 2 wetland be restored or created; if wetland enhancement were proposed (subsection M12d(i) of this Section) for the Category 2, forested wetland, 1.5 acres of forested Category 2 wetland would have to be created/restored and two (2) acres of forested Category 2 wetland enhanced, possibly in a different part of the same wetland.

i. RATIOS FOR WETLAND RESTORATION OR CREATION PLUS ENHANCEMENT
Wetland Category	Vegetation Type	Restoration or Creation Ratio		Enhancement Ratio
Category 1	Forested Scrub-shrub Emergent	3 times the area altered 1.5 times the area altered 1 times the area altered	plus plus plus	3.5 times the area altered 2 times the area altered 1.5 times the area altered
Category 2	Forested Scrub-shrub Emergent	1.5 times the area altered 1 times the area altered 1 times the area altered	plus plus plus	2 times the area altered 1.5 times the area altered 1 times the area altered
Category 3	Forested Scrub-shrub Emergent	1 times the area altered 1 times the area altered 1 times the area altered	plus plus plus	1 times the area altered 1 times the area altered 1 times the area altered

e. Ratio Modification and Minimum Restoration/Creation Ratio:

i. An applicant may propose an increased creation or restoration ratio and a decreased enhancement ratio if the total combined ratio is maintained overall. Restoration/creation or enhancement ratios shown in subsection M12d of this Section may only be reduced by modification or variance pursuant to subsection N3 of this Section, Alternatives, Modifications and Variances, and RMC 4-9-250B, Variance Procedures, and RMC 4-9-250D, Modification Procedures. In order to maintain no net loss of wetland acreage, in no case shall the restoration or creation ratio be less than 1:1. This minimum ratio may not be modified through the variance process.

ii. Ratios may be increased under the following circumstances: uncertainty as to the probable success of the proposed restoration or creation or enhancement proposal; significant period of time between destruction and replication of wetland functions; projected losses in functional value; or off-site compensation. The requirement for an increased mitigation ratio will be determined through SEPA review, except in the case of remedial actions resulting from illegal alterations where the Administrator or Environmental Review Committee may require increased mitigation ratios. (Ord. 5676, 12-3-2012)

13. Out-of-Kind Replacement: Out-of-kind replacement may be approved in place of in-kind compensation only where the applicant can demonstrate that:

a. The wetland system is already significantly degraded and out-of-kind replacement will result in a wetland with greater functional value; or

b. Scientific problems such as exotic vegetation and changes in watershed hydrology make implementation of in-kind compensation impossible or unacceptable; or

c. Out-of-kind replacement will best meet identified regional goals (e.g., replacement of historically diminished wetland types). (Ord. 5676, 12-3-2012)

14. Off-Site Compensation:

a. When Permitted: Off-site compensation may be approved in lieu of on-site compensation only where the applicant can demonstrate that:

i. The hydrology and ecosystem of the original wetland and those abutting or adjacent land and/or wetlands which benefit from the hydrology and ecosystem will not be substantially damaged by the on-site loss; and

ii. On-site compensation is not feasible due to problems with hydrology, soils, or other factors; or

iii. Compensation is not practical due to potentially adverse impact from surrounding land uses; or

iv. The proposed wetland functions at the mitigation site are significantly greater than the wetland functions that could be reasonably achieved with on-site mitigation, and there is no significant loss of function on-site, i.e., at the development project site; or

v. Established regional goals for flood storage, flood conveyance, habitat or other wetland functions have been addressed and strongly justify location of compensatory measures at another site. (Ord. 5676, 12-3-2012)

b. Locations: Any off-site compensation shall follow the preferences in subsections M14b(i) to (iii) of this Section. Basins and subbasins are indicated in subsection Q of this Section, Maps:

i. Off-Site Mitigation within Same Drainage Subbasin as Subject Site: Off-site mitigation may be allowed when located within the same drainage subbasin as the subject site subject to criteria in subsection M14a of this Section;

ii. Off-Site Mitigation within Same Drainage Basin within City Limits: Off-site mitigation may be allowed when located within the same drainage basin within the Renton City limits if it achieves equal or improved ecological functions within the City over mitigation within the same drainage subbasin as the project, and shall be subject to criteria in subsection M14a of this Section;

iii. Off-Site Mitigation within the Same Drainage Basin Outside the City Limits: Off-site mitigation may be allowed when located within the same drainage basin outside the Renton City limits if it achieves equal or improved ecological functions over mitigation within the same drainage basin within the Renton City limits and it meets City goals, and shall be subject to criteria in subsection M14a of this Section.

c. Siting Recommendations: In selecting compensation sites, the City encourages applicants to pursue siting compensation projects in disturbed sites which were formerly wetlands, and especially those areas which would result in a series of interconnected wetlands.

d. Timing: Compensatory projects shall be substantially completed and approved by the City prior to the issuance of an occupancy permit. Construction of compensation projects shall be timed to reduce impacts to existing wildlife and flora. A surety device may be approved for completion of construction. (Ord. 5676, 12-3-2012)

15. Cooperative Wetland Compensation: Mitigation Banks or Special Area Management Programs (SAMP):

a. Applicability: The City encourages and will facilitate and approve cooperative projects wherein a single applicant or other organization with demonstrated capability may undertake a compensation project under the following circumstances:

i. Restoration or creation on-site may not be feasible due to problems with hydrology, soils, or other factors; or

ii. Where the cooperative plan is shown to better meet established regional goals for flood storage, flood conveyance, habitat or other wetland functions.

b. Process: Applicants proposing a cooperative compensation project shall:

i. Submit a permit application;

ii. Demonstrate compliance with all standards;

iii. Demonstrate that long-term management will be provided; and

iv. Demonstrate agreement for the project from all affected property owners of record.

c. Mitigation Banks: Mitigation banks are defined as sites which may be used for restoration, creation and/or mitigation of wetland alternatives from a different piece of property than the property to be altered within the same drainage basin. The City of Renton maintains a mitigation bank. A list of City mitigation bank sites is maintained by the Public Works Department. With the approval of the Public Works Department, non-City-controlled mitigation banks may be established and utilized. (Ord. 5450, 3-2-2009)

d. Special Area Management Programs: Special area management programs are those wetland programs agreed upon through an interjurisdictional planning process involving the U.S. Army Corps of Engineers, the Washington State Department of Ecology, any affected counties and/or cities, private property owners and other parties of interest. The outcome of the process is a regional wetlands permit representing a plan of action for all wetlands within the special area.

e. Compensation Payments to Mitigation Bank: If approved, compensation payments received as part of a mitigation or creation bank must be received prior to the issuance of an occupancy permit. (Ord. 5676, 12-3-2012)

16. Mitigation Plans:

a.  Required for Restoration, Creation and Enhancement Projects: All wetland restoration, creation, and enhancement in conjunction with restoration and creation projects required pursuant to this Section either as a permit condition or as the result of an enforcement action shall follow a mitigation plan prepared by qualified wetland specialists approved by the City.

b. Timing for Mitigation Plan Submittal and Commencement of any Work: See subsection F8 of this Section.

c. Content of Mitigation Plan: Unless the City, in consultation with qualified wetland specialists, determines, based on the size and scope of the development proposal, the nature of the impacted wetland and the degree of cumulative impacts on the wetland from other development proposals, that the scope and specific requirements of the mitigation plan may be reduced, the mitigation plan shall address all requirements in RMC 4-8-120D23, Wetland Mitigation Plan, and subsection F8 of this Section.

d. Performance Surety: As a condition of approval of any mitigation plan, a performance surety shall be required per RMC 4-1-230 and subsection G of this Section. (Amd. Ord. 4851, 8-7-2000; Ord. 5137, 4-25-2005; Ord. 5676, 12-3-2012)

N. ALTERNATES, MODIFICATIONS AND VARIANCES:

1. Alternates:

a. Applicability: See RMC 4-9-250E.

2. Modifications:

a. Applicability: The Department Administrator may grant modifications, per RMC 4-9-250D1, Application Time and Decision Authority, in the following circumstances:

i. Aquifer Protection – Modifications: The Department will consider modification applications in the following cases:

(a) The request is to find that a standard is inapplicable to that activity, facility, or development permit due to the applicant’s proposed methods or location; or

(b) The request is to modify a specific standard or regulation due to practical difficulties; and

(c) The request meets the intent and purpose of the aquifer protection regulations.

Based upon application of the above tests in subsection N2a(i)(a), (b), and (c) of this Section, applications which are considered appropriate for review as modifications are subject to the procedures and criteria in RMC 4-9-250D, Modification Procedures. Requests to modify regulations or standards which do not meet the above tests shall be processed as variances.

(d) In addition to the criteria of RMC 4-9-250D, Modification Procedures, the following criteria shall apply: The proposed modification is based on consideration of the best available science as described in WAC 365-195-905; or where there is an absence of valid scientific information, the steps in RMC 4-9-250F are followed.

ii. Geologic Hazards – Modifications: An applicant may request that the Administrator grant a modification to allow:

(a) Regrading of any slope which was created through previous mineral and natural resource recovery activities or was created prior to adoption of applicable mineral and natural resource recovery regulations or through public or private road installation or widening and related transportation improvements, railroad track installation or improvement, or public or private utility installation activities;

(b) Filling against the toe of a natural rock wall or rock wall created through mineral and natural resource recovery activities or through public or private road installation or widening and related transportation improvements, railroad track installation or improvement or public or private utility installation activities; and/or

(c) Grading to the extent that it eliminates all or portions of a mound or to allow reconfiguration of protected slopes created through mineral and natural resource recovery activities or public or private road installation or widening and related transportation improvements, railroad track installation or improvement, or public or private utility installation activities.

The following procedures shall apply to any of the above activities:

(1) The applicant shall submit a geotechnical report describing any potential impacts of the proposed regrading and any necessary mitigation measures;

(2) All submitted reports shall be independently reviewed by qualified specialists selected by the City at the applicant’s expense;

(3) The Department Administrator may grant, condition, or deny the request based upon the proposal’s compliance with the applicable modification criteria of RMC 4-9-250D; and

(4) Any slope which remains forty percent (40%) or steeper following site development shall be subject to all applicable geologic hazard regulations for steep slopes and landslide hazards, in this Section.

(5) In addition to the criteria of RMC 4-9-250D, Modification Procedures, the following criteria shall apply: The proposed modification is based on consideration of the best available science as described in WAC 365-195-905; or where there is an absence of valid scientific information, the steps in RMC 4-9-250F are followed.

iii. Wetlands – Modifications: An applicant may request that the Administrator grant a modification as follows:

(a) Modifications may be requested for a reduction in creation/restoration or enhancement ratios for a Category 3 wetland; however, the creation/restoration ratio shall not be reduced below 1:1.

(b) In addition to the criteria of RMC 4-9-250D, Modification Procedures, the following criteria shall apply:

(1) The proposal will result in no-net loss of wetland or buffer area and functions.

(2) The proposed modification is based on consideration of the best available science as described in WAC 365-195-905; or where there is an absence of valid scientific information, the steps in RMC 4-9-250F are followed.

iv. Streams – Modifications: An applicant may request that the Administrator grant a modification as follows:

(a) Modifications may be requested for a reduction in stream buffers for Class 2 or 3 watercourses proposed to be daylighted, below the stream buffer reduction levels of subsection L5c of this Section.

(b) In addition to the criteria of RMC 4-9-250D, Modification Procedures, the following criteria shall apply:

(1) The buffer is lowered only to the amount necessary to achieve the same amount of development as without the daylighting.

(2) The buffer width is no less than fifty feet (50') on a Class 2 watercourse and twenty five feet (25') on a Class 3 watercourse.

(3) The proposed modification is based on consideration of the best available science as described in WAC 365-195-905; or where there is an absence of valid scientific information, the steps in RMC 4-9-250F are followed.

3. Variances:

a. Aquifer Protection – Variance:

i. Applicability: If an applicant feels that the strict application of this Section would deny all reasonable use of the property or would deny installation of public transportation or utility facilities determined by the public agency proposing these facilities to be in the best interest of the public health, safety and welfare, the applicant of a development proposal may apply for a variance.

ii. Application Submittal: An application for a variance shall be filed with the Development Services Division.

iii. Review Authority: A variance shall be decided by the Administrator based on the standards set forth in RMC 4-9-250B, Variance Procedures. (Ord. 5519, 12-14-2009)

b. Flood Hazards – Variances:

i. Applicability: Refer to RMC 4-9-250B.

c. Geologic Hazards, Habitat Conservation, Streams and Lakes – Classes 2 to 4, and Wetlands – Variance:

i. Applicability: If an applicant feels that the strict application of this Section would deny all reasonable use of the property containing a critical area or associated buffer, or would deny installation of public transportation or utility facilities determined by the agency proposing these facilities to be in the best interest of the public health, safety and welfare, the public agency or an applicant of a development proposal may apply for a critical areas variance.

ii. Application Submittal: An application for a critical areas variance shall be filed with the Development Services Division.

iii. Review Authority: Variances shall be determined administratively by the Community and Economic Development Administrator, as indicated in RMC 4-9-250B. (Amd. Ord. 4851, 8-7-2000; Ord. 5137, 4-25-2005; Ord. 5519, 12-14-2009; Ord. 5676, 12-3-2012)

O. APPEALS:

1. General: See RMC 4-8-070, Authority and Responsibilities, and RMC 4-8-110.

2. Record Required – Flood Hazards: The Administrator shall maintain the records of all appeal actions and report any variances to the Federal Insurance Administration upon request. (Amd. Ord. 4851, 8-7-2000; Ord. 4963, 5-13-2002; Ord. 5137, 4-25-2005; Ord. 5676, 12-3-2012)

P. ASSESSMENT RELIEF – WETLANDS:

1. City Assessments: Such landowner should also be exempted from all special City assessments on the controlled wetland to defray the cost of municipal improvements such as sanitary sewers, storm sewers, water mains and streets. (Ord. 5000, 1-13-2003; Ord. 5137, 4-25-2005)

Q. MAPS:

1. Aquifer Protection: See Figure 4-3-050Q1 for reference map.

2. Flood Hazards: see Figure 4-3-050Q2 for reference map.

3. Geologic Hazards:

a. Coal Mine Hazards:

i. Map: See Figure 4-3-050Q3a(i) for reference map.

ii. Mapping Criteria:

(a) Low Coal Mine Hazards (CL): Areas not identified as high or medium hazards. While no mines are known in these areas, undocumented mining is known to have occurred.

(b) Medium Coal Mine Hazards (CM):

(1) Lands overlying coal mines, but not included in the high hazard category; and

(2) Surrounding lands overlying a wedge between a plane rising vertically from the mine and a plane rising from the mine at a break angle of between twenty five (25) and forty (40) degrees. The break angle is measured from the vertical. The break angle appropriate for the given seam is determined by the slope of the seam and the workings. Approximate mine depths and seam dip and break angles are provided in Appendices C and D of the Summary Report, Critical and Resource Areas Evaluation, GeoEngineers, 1991.

(c) High Coal Mine Hazard (CH): All lands where underlying coal mines are within two hundred feet (200') below the ground surface, or fifteen (15) times the height of the mine workings below the surface, whichever is less.

b. Erosion Hazards:

i. Map: See Figure 4-3-050Q3b(i) for reference map.

ii. Mapping Criteria:

(a) Low Erosion Hazard (EL): All surface soils on slopes less than fifteen percent (15%). Mapped areas include all Natural Resource Conservation Service (formerly U.S. Soil Conservation Service) soils designated A, B, or C.

(b) High Erosion Hazard (EH): All surface soils on slopes steeper than fifteen percent (15%). Mapped areas include all Natural Resource Conservation Service (formerly U.S. Soil Conservation Service) soils designated as D, E, or F.

c. Landslide Hazards:

i. Map: See Figure 4-3-050Q3c(i) for reference map.

ii. Mapping Criteria:

(a) Low Landslide Hazard (LL): Areas with slopes less than fifteen percent (15%).

(b) Medium Landslide Hazard (LM): Areas with slopes between fifteen percent (15%) and forty percent (40%) where the surface soils are underlain by permeable geologic units. The permeable units include:

(1) Fill: af, afm, and m;

(2) Alluvium: Qac, Qaw, Qas, and Qa;

(3) Vashon recessional and advance glacial deposits: Qik, Qit, Qiv, Qpa, Qis, Qys, Qyg, Qvr, Qsr, and Qos;

(4) Vashon glacial deposits: Qg, Qgt, Qt, and Qvt.

(c) High Landslide Hazards (LH): Areas with slopes greater than forty percent (40%) and areas with slopes between fifteen percent (15%) and forty percent (40%) where the surface soils are underlain by low permeability geologic units. The low permeability units include:

(1) Post-glacial lake and peat silts: Qlp, Qp, Qlm, and Qvl;

(2) Pre-Vashon Pleistocene deposits: Qss, Qu, Qc, Qcg, and Qog;

(3) Tertiary rock formations: Ts, Ti, Tr, Tt, Tet, Ttu, Tta, Teta, and Ttl.

(d) Very High Landslide Hazards (LV): All mapped landslide deposits: Qmc, Qm, Ql, and landslides known from public records.

d. Seismic:

i. Map: See Figure 4-3-050Q3d(i) for reference map.

ii.  Mapping Criteria:

(a) Low Seismic Hazard (SL): All Vashon age glacial and older sediments. The mapped areas include:

(1) All deposits of recessional and advance glacial deposits: Qik, Qit, Qiv, Qpa, Qis, Qys, Qyg, Qur, Qsr, Qos, Qog.

(2) Vashon glacial deposits: Qg, Qgt, Qt, and Qvt;

(3) Pre-Vashon Pleistocene deposits: Qss, Qu, Qc, and Qcg;

(4) Tertiary rock formations: Ts, Ti, Tr, Tt, Tet, Ttu, Tta, Teta, and Ttl;

(5) Areas of roadway fill, af and afm, which overlay the above units.

(b) High Seismic Hazard (SH): Post-glacial deposits which are likely to be saturated as they occupy low areas and frequently overlay low permeability deposits. They include:

(1) Deposits of fill: af, afm, and m;

(2) Alluvium: Qaw, Qac, Qas, and Qa;

(3) Mass wasting deposits: Qmc, Qm, and Ql;

(4) Post-glacial lake silts and peats: Qlp, Qp, Qlm, and Qvl.

e. Steep Slopes:

i. Map: Refer to the City of Renton Steep Slope Atlas and Figure 4-3-050Q3e(i) for reference map.

f. Volcanic Hazards: Volcanic hazard areas are those areas subject to a potential for inundation from post lahar sedimentation along the lower Green River as identified in Plate II, Map D, in the report U.S. Department of the Interior, U.S. Geological Survey (Revised 1998), Volcano Hazards from Mount Rainier, Washington. Open-File Report 98-428.

4. Streams and Lakes: See Figure 4-3-050Q4 for reference map identifying Class 2 to 4 water bodies. Water class shall be determined in accordance with subsection L1 of this Section. For Class 1 waters, refer to RMC 4-3-090, Shoreline Master Program Regulations.

5. Wetlands: Refer to the City of Renton Wetland and Stream Corridors Critical Areas Inventory and see Figure 4-3-050Q5 for reference map.

6. Drainage Basins: See Figures 4-3-050Q6a and b for maps identifying basins and subbasins in the Renton vicinity.

Figure 4-3-050Q1
AQUIFER PROTECTION ZONES

Figure 4-3-050Q2
FLOOD HAZARDS

Figure 4-3-050Q3a(i)
COAL MINE HAZARDS

Figure 4-3-050Q3b(i)
EROSION HAZARDS

Figure 4-3-050Q3c(i)
LANDSLIDE HAZARDS

Figure 4-3-050Q3d(i)
SEISMIC HAZARDS

Figure 4-3-050Q3e(i)
STEEP SLOPES

Figure 4-3-050Q4
STREAMS AND LAKES

(Amd. Ord. 5355, 2-25-2008; Ord. 5468, 7-13-2009; Ord. 5675, 12-3-2012)

Figure 4-3-050Q5
WETLANDS

Figure 4-3-050Q6a
SURFACE WATER FACILITIES BASINS

Figure 4-3-050Q6b
SURFACE WATER FACILITIES SUB-BASINS

(Amd. Ord. 4992, 12-9-2002; Ord. 4851, 8-7-2000; Ord. 5137, 4-25-2005)

R. GENERIC HAZARDOUS MATERIALS LIST:

GENERIC HAZARDOUS MATERIALS LIST FOR INFORMATIONAL USE ONLY
Acid and basic cleaning solutions Antifreeze and coolants Arsenic and arsenic compounds Battery acid Bleaches, peroxides Brake and transmission fluids Brine solution Casting and foundry chemicals Caulking agents and sealants Cleaning solvents Cooling water (not isolated from process chemicals) Corrosion and rust prevention solutions Cutting fluids Degreasing solvents Deicing materials Disinfectants Dyes Electroplating solutions Engraving solutions Etching solutions Explosives Fertilizers Food processing wastes Formaldehyde Fuels and additives Glues, adhesives, and resins Greases Hydraulic fluid Indicators Industrial and commercial janitorial supplies Industrial sludges and stillbottoms Inks, printing, and photocopying chemicals Laboratory chemicals Medical, pharmaceutical, dental, veterinary, and hospital solutions Metal dusts Mercury and mercury compounds Metals finishing solutions Oils Paints, pigments, primers, thinners, dyes, stains, wood preservatives, varnishing, and cleaning compounds Painting solvents PCBs Pesticides and herbicides Plastic resins, plasticizers, and catalysts Photo development chemicals Poisons Polishes Pool chemicals

 

GENERIC HAZARDOUS MATERIALS LIST FOR INFORMATIONAL USE ONLY
Processed dust and particulates Radioactive sources Reagents and standards Refrigerants Roofing chemicals and sealers Sanitizers, disinfectants, bactericides, and algaecides Soaps, detergents and surfactants Solders and fluxes Stripping compounds Tanning industry chemicals Transformer and capacitor oils/fluids Wastewater treatment sludges

(Ord. 4851, 8-7-2000)

S. PIPELINE MATERIAL:

1. PIPELINE MATERIAL REQUIREMENT
	Pipe Diameter in Inches						Suggested Material Spec	Considerations (See subsection S2)
Pipe Material	<4	4-8	10-12	14-20	24-30	36-54
Ductile Iron, Rubber Gaskets Cement Mortar-Lined Polyethylene-Lined Ductile Iron, Nitrile Gaskets Cement Mortar-Lined Polyethylene-Lined		1,2 1,2   1,2 1,2,3	1,2 1,2   1,2 1,2,3	1,2 1,2   1,2 1,2,3	1,2 1,2   1,2 1,2,3	1,2 1,2   1,2 1,2,3	AWWA C151, C104 AWWA C151   AWWA C151, C104 AWWA C151	abcdnopr abcdnopr   bcdinopr bcdeinopr
PVC, Rubber Gasket Joints CL 150 or 200 SDR 35 PVC, Nitrile Gasket Joints CL 150 or 200 PVC, Solvent Welded Joints Sch 80	1,2 1     2,3	1,2 1 1,2,3   1,2,3	1,2   1,2,3   1,2,3				AWWA C900 ASTM D3034 AWWA C900   ASTM D1784, D1785	abjlnoprt   bijlnoprt   hjklnoprt
Welded Steel, Rubber Gaskets Cement Mortar-Lined Dielectric-Lined Welded Steel, Welded Joints Cement Mortar-Lined Dielectric-Lined		1,2 1,2	1,2 1,2	1,2 1,2	1,2 1,2   1,2 1,2,3	1,2 1,2   1,2 1,2,3	AWWA C200, C205 AWWA C200, C210   AWWA C200, C205 AWWA C200, C210	abfghnopr abfghnopr   fghnopr fghnopr
High Density Polyethylene Pipe Corrugated High Density Polyethylene Pipe - Smooth Interior		1,2   1	1,2   1	1,2   1	1,2   1	1   1	ASTM D1248 and D3350 ASTM D1248 and AASHTO	hkpqu   kpqsu
Slip Form Liner		4,5	4,5	4,5	4,5	4,5	ASTM D638	mnopqr
PIPELINE SERVICE 1. Storm Sewer 2. Sanitary Sewer and Side Sewer 3. Leachate Pipeline 4. Rehab Existing Storm Sewer 5. Rehab Existing Sanitary Sewer
2. CONSIDERATIONS ON SELECTION OF PIPE MATERIALS
The Utility maintains a list of materials meeting performance standards. Other materials meeting similar performance standards or developed as the result of new technology may be approved by the Utility.
a.    Rubber gaskets may be severely damaged by petroleum products, particularly in prolonged exposures to concentrated flows containing little or no stormwater or sanitary sewage. In cases where heavy concentrations of petroleum products may be experienced, nitrile (Nitrile-Butadiene; i.e., NBR) gaskets should be used.
b.    Gasketed joints may not be leak-proof at zero or low pressures, if improperly installed.
c.    Mechanical joints may be less likely to leak at low pressures than push-on joints.
d.    May need protective coatings and/or cathodic protection against external corrosion.
e.    Considered most reliable gasket and lining material for ductile iron leachate pipeline.
f.    Very difficult to repair linings on inside of joints in pipe smaller than 24-inch diameter.
g.    Almost always needs protective coatings and cathodic protection against external corrosion.
h.    Properly made joints are considered leak-proof.
i.    Nitrile gaskets may require long delivery time.
j.    Requires special attention to bedding and backfill depth to avoid structural failure of pipe.
k.    Large thermal expansion coefficient. May need to limit solvent welded joints to 4-inch and smaller pipe. May require careful evaluation of pipe installation temperature and temperature of piped liquids to ensure joint integrity.
l.    Pipe not available over 12-inch diameter.
m.    Slip form lining is available in 6-inch through 60-inch diameter for almost any pressure, if sufficient pipe cross-sectional area is available.
n.    Pressure grouts and gels are not acceptable for rehabilitation or patching of storm and sanitary sewers.
o.    Suitability of pipe lining and gasket material to resist chemical attack by conveyed fluids must be determined for each pipeline service considered.
p.    All storm and sanitary sewer manholes, catch basins, and inlets should be equipped with precast concrete bottom and sidewalls with rubber gasketed joints between sections, water-tight epoxy grout or other approved pipe entrances through walls, and approved waterproof coating of all interior floor and wall surfaces. Manholes, catch basins, and inlets should have no leakage when hydrostatically tested at atmospheric pressure.
q.    Has good resistance to a number of chemicals, petroleum products, and hydrogen sulfide corrosion.
r.    “Zero leakage” test requirement may be impossible to achieve under the best conditions for any pipe materials because trapped air may distort test results, even in a drop-tight pipe. Pressure and leakage test requirements should consider whether the pipe has steep slope or will stand full of liquid. Pipelines should be tested with the intent to prevent or minimize leakage. Air testing should not be allowed; hydrostatic testing should be as stringent as any found in the industry. Pipe materials, without regard for chemical attack, corrosion, or puncture, are generally ranked as follows, in decreasing order of liquid-tight reliability: •    welded steel with welded joints •    PVC with solvent welded joints •    slip form liner •    ductile iron with viton or rubber gaskets •    welded steel with rubber gasketed joints •    PVC with viton or rubber gasketed joints
s.    Joints should consist of “heat-shrink” wrap, standard corrugated coupling, and full pipe band clamps.
t.    The use of PVC may be restricted by other Utility policy in regards to depth of pipe cover.
u.    HDPE may be adversely affected by solvents; its use is not recommended where contact with solvents may occur.

(Ord. 4851, 8-7-2000)