4-4-060 GRADING, EXCAVATION AND MINING REGULATIONS:

A. PURPOSE:

It is the purpose of this Section to:

1. Provide a means of regulating mining, excavation and grading to promote the health, safety, morals, general welfare and esthetics in the City of Renton.

2. Promote the progressive rehabilitation of mining, excavation and grading sites to a suitable new use.

3. Protect those areas and uses in the vicinity of mining, excavation and grading activities against detrimental effects.

4. Promote safe, economic, systematic and uninterrupted mining, excavation and grading activities within the City of Renton.

5. Minimize adverse stormwater impacts generated by the removal of vegetation and alteration of landform in order to comply with the requirements of the National Pollutant Discharge Elimination System (NPDES) Phase II Municipal Stormwater Permit.

6. Protect water quality from the adverse impact associated with erosion and sedimentation in order to comply with the requirements of the National Pollutant Discharge Elimination System (NPDES) Phase II Municipal Stormwater Permit. (Ord. 5526, 2-1-2010)

B. SCOPE:

1. Applicability: All mining, excavation and grading activities within the City of Renton shall be subject to the terms and conditions of this Section. All such activities shall be further in compliance with chapter 78.44 RCW and subject to the terms of this Section.

2. Application Required for Existing Activities: The owner or operator of such activities in the City at the time of the adoption of this Section shall make the initial application within thirty (30) days and the entire application within ninety (90) days of the effective date of this Section.

3. Application Required for Activities Annexed into City: The owner or operator of such activities annexed subsequent to the adoption of this Section shall make the initial application within thirty (30) days and the entire application within ninety (90) days from the date of annexation.

4. Time for Compliance: All such existing activities shall comply fully with all provisions of this Section within the period of time established by this Section except such activities which are not existing at the date of the adoption of this Section shall conform to all provisions of this Section prior to the beginning of their operation.

C. GENERAL:

1. Landscaping: Existing vegetation in any required setback shall be preserved or landscaping shall be planted to prevent erosion and reduce the dust, mud and noise generated on the proposed reuse of the site. Around the periphery of the site, except where the proposed reuse of the site requires the lack of vegetation, the applicant shall landscape in such a manner as to result in reasonable screening. Trees planted shall be at least four feet (4') in height. In those areas that have been rehabilitated and are designated to be planted according to the proposed reuse of the site, the appropriate plantings shall be done as soon as possible to provide mature plants for the new use.

2. Screening: With the exception of offices, every effort shall be made to screen effectively all structures and activities to minimize detrimental effects on adjacent or abutting property. Screening may include but is not limited to landscaping, berms with landscaping, and a screening fence. (Ord. 5676, 12-3-2012)

3. Natural Stream Courses: Every effort shall be made to preserve perennial and intermittent streams and their surrounding vegetation. (Ord. 2820, 1-14-1974, eff. 1-19-1974)

4. Hydroseeding Required: Within thirty (30) days of completion of grading work, the applicant shall hydroseed or plant an appropriate ground cover over any portion of the site that is graded or cleared of vegetation and where no further construction work will occur within ninety (90) days. Alternative measures such as mulch, sodding, or plastic covering as specified in the Surface Water Design Manual may be proposed between the dates of October 1st and April 30th of each year. The Development Services Division’s approval of this work is required prior to final inspection and approval of the permit. (Ord. 4703, 2-2-1998; Ord. 5526, 2-1-2010)

5. Conformance with RCW: This Section conforms to the requirements of chapter 78.44 RCW which regulates surface mining in the State of Washington. (Ord. 2820, 1-14-1974, eff. 1-19-1974)

6. Notification of Noncompliance: It shall be the responsibility of the certifying engineer on any grading project to advise immediately any discrepancies, hazardous conditions or problems affecting safety and stability of the project to the person in charge of the grading work and subsequently in writing to the grading operator and to the Building Department. Recommendations for corrective measures, if necessary, shall be provided in the correction notices.

7. Transfer of Responsibility for Work: If at any time the grading operator changes the certifying engineer or a different ownership or responsible party occurs, the operator shall notify the Building Department in writing within ten (10) days and shall specify the new civil engineer or owner. The owner or grading operator shall not be relieved of any responsibility relative to the safety and conduct of a grading operation by virtue of changing engineering advisors.

8. Stop Work Order: Should hazardous conditions occur in either engineered grading or regular grading, the Building Department inspector shall have the responsibility and authority to issue a partial or total stop work order.

9. Emergency Permits: Upon application to the Development Services Division, supported by those plans adequate for the Director of the Development Services Division to make a decision, there may be declared an emergency and the Director may issue an emergency fill and grade permit. In order for there to be declared an emergency, there must be a declaration from a State or Federal regulatory agency that an emergency condition exists that threatens public safety, health or welfare, or the Development Services Division Director must be presented with independent evidence that there exists an emergency that imminently threatens public safety, health or welfare, and further that there exists inadequate time to obtain a fill and grade permit. Before the emergency permit can be issued, the Director must ensure that environmental review has been completed by the Environmental Review Committee or is under the supervision of a Federal or State agency that has conducted environmental review. As part of any emergency grading, the applicant for an emergency permit must provide a disposal plan of the materials satisfactory to the Director, including routing of any vehicles transporting any contaminated, dangerous or toxic materials. Any fill to be installed must comply with the requirements of this Section concerning the contents of the fill. An emergency fill and grading permit shall be for the minimum time and minimum volume necessary to avoid the emergency. (Ord. 4102, 12-14-1987, eff. 12-19-1987)

D. GENERAL EROSION AND SEDIMENT CONTROL STANDARDS:

1. Erosion and Sediment Control Required: A person who clears, grades or otherwise disturbs a site shall provide erosion and sediment control that prevents, to the maximum extent practicable, the transport of sediment from the site to drainage facilities, water resources and adjacent properties. Erosion and sediment controls shall be applied as specified by the temporary erosion and sediment control measures and performance criteria and implementation requirements in the Surface Water Design Manual adopted in accordance with RMC 4-6-030.

2. Seasonal Limitations: From October 1st through April 30th, which is the seasonal limitation period, clearing and grading shall only be permitted if shown to the satisfaction of the Director that runoff leaving the construction site will comply with the erosion and sediment control measures and performance criteria and implementation requirements in the Surface Water Design Manual through a combination of the following:

a. Site conditions including vegetative coverage, slope, soil type and proximity to receiving waters; and

b. Proposed limitations on activities and the extent of disturbed areas; and

c. Proposed erosion and sedimentation control measures.

3. Expansion or Restriction of Seasonal Limitations: Based on the information provided under subsection D1 of this Section, the Community and Economic Development Administrator may expand or restrict the seasonal limitations on site disturbance. The Administrator shall set forth in writing the basis for approval or denial of clearing or grading during the seasonal limitation period. (Ord. 5676, 12-3-2012)

4. Approved Erosion and Sediment Control Plan Required: During the seasonal limitation period, clearing and grading will be allowed only if there is installation and maintenance of an erosion and sedimentation control plan approved by the City of Renton Development Services Division that defines any limits on clearing and grading or specific erosion and sediment control measures required during the seasonal limitation period. The Development Services Division may require or approve alternate best management practices.

5. Violation: If, during the course of construction activity or soil disturbance during the seasonal limitation period, silt-laden runoff violating standards in the Surface Water Design Manual leaves the construction site or if clearing and grading limits or erosion and sediment control measures shown in the approved plan are not maintained, the department inspector shall have the responsibility and authority to issue a partial or total stop work order.

6. Continued Violation: If the erosion and sediment control problem defined in the stop work order is not adequately repaired within twenty four (24) hours of issuance, then a notice and order may be issued to install adequate erosion and sediment control measures to stop silt-laden runoff from leaving the site. The order may also require the property owner to discontinue any further clearing or grading, except for erosion and sediment control maintenance and repair, until the following April 30th. (Ord. 5526, 2-1-2010)

E. BOND REQUIRED TO COVER COSTS OF REHABILITATION:

The Development Services Division shall require bonds amounting to one and one-half (1-1/2) times the estimated cost of rehabilitation to assure that the work, if not completed or proceeding in accordance with the approved plans and specifications, shall be corrected. Such a bond shall be approved by the City Attorney and filed with the City Clerk. In lieu of a surety bond, the applicant may file a cash bond or instrument of credit with the City Clerk in an amount equal to that which would be required in the surety bond. The bond shall be conditioned upon the faithful performance of the requirements as set forth in this Section. Any reclamation bonds posted with the State Department of Natural Resources for surface mining permits may be applied on the bond requirements, insofar as they pertain to the reclamation provisions of this Section. (Ord. 5526, 2-1-2010)

F. INSPECTION:

1. Inspection Authorized: All operations regulated by this Section shall be subject to inspection by authorized Development Services Division inspection personnel. When extraordinary or special problems or conditions are involved, extra inspection of grading operations and special tests may be ordered by the City.

2. Entry to be Permitted: No owner or occupant or any other person having charge, care or control of any building, land, structure, premises or portion thereof shall fail or neglect, after proper demand, to promptly permit lawful entry thereon by the Development Services Division inspection personnel for the purpose of inspection and examination pursuant to this Section. (Ord. 2820, 1-14-1974, eff. 1-19-1974; Amd. Ord. 3592, 12-14-1981; Ord. 5526, 2-1-2010)

G. RESTORATION OF HAZARD REQUIRED:

Whenever the Community or Economic Development Administrator determines that an existing site, as a result of clearing or grading, excavation, embankment, or fill has become a hazard to life and limb, or endangers property, or adversely affects the safety, use or stability of a public way or drainage channel, the owner of the property upon which the clearing, grading, excavation or fill is located, or other person or agent in control of said property, upon receipt of notice in writing from the Administrator, shall within the period specified therein restore the site affected by such clearing or grading or repair or eliminate such excavation or embankment or fill so as to eliminate the hazard and be in conformance with the requirements of this Chapter. (Ord. 5526, 2-1-2010; Ord. 5676, 12-3-2012)

H. ENGINEERING GRADING REQUIREMENTS:

1. Reports Required: Soil engineering and geotechnical reports shall be required as defined in RMC 4-11-190 and 4-11-190. During grading all necessary reports, compaction data and soil engineering and engineering geology recommendations shall be submitted to the civil engineer and the Public Works Department by the soil engineer and the engineering geologist. The Public Works Department may waive reports for minor grading operations.

2. Civil Engineer Responsibilities: For purposes of preparing and/or approving engineered grading plans, the engineer shall be a professional engineer registered in the State to practice in the field of civil works. The civil engineer shall be responsible for the plans, any special soil engineering and testing reports, design of drainage facilities and structures, and be competent to recommend and obtain special tests, survey data, and geological or hydraulic reports should they be necessary. The civil engineer shall provide an acceptable plan and report based on good engineering practices and the requirements designated by the Public Works Department. He shall, upon return of his plans, provide any corrections necessary and corrected copies for use of the City in reviewing the grading work. The civil engineer shall be responsible for reporting monthly or more frequently on forms provided by the Public Works Department:

a. Extent and location of grading.

b. All tests made or taken in conjunction with the grading operation.

c. Extent of drainage, structure, and safety activity report on the project.

d. Any special testing, as-built plans or revised requests necessary.

In addition, he shall certify to the safety and stability of the slopes, safety earthwork operation, and special problems which might occur.

3. Soil Engineer Responsibilities: The soil engineer’s area of responsibility shall include but need not be limited to the professional inspection and certification concerning the preparation of ground to receive fills, testing for required compaction, stability of all finish slopes and the design of buttress fills, where required, incorporating data supplied by the engineering geologist.

4. Engineering Geologist Responsibilities: The engineering geologist’s area of responsibility shall include but need not be limited to professional inspection and certification of the adequacy of natural ground for receiving fills and the stability of cut slopes with respect to geological matters, and the need for subdrains or other groundwater drainage devices. He shall report his findings to the soil engineer and the civil engineer for engineering analysis. (Ord. 2820, 1-14-1974, eff. 1-19-1974)

5. Building Division Responsibilities: The Building Division shall inspect the project at frequent intervals to determine that adequate control is being exercised by the operator and the civil engineer. Should hazardous conditions occur, the Building Department inspector shall have the responsibility and authority to issue a partial or total stop work order. (Ord. 2820, 1-14-1974, eff. 1-19-1974, Amd. Ord. 3592, 12-14-1981)

6. Specifications: A fence six feet (6') in height with openings no larger than two inches (2") (other than gates) may be required for safety reasons completely around any area worked upon for which a permit is issued for engineered grading prior to commencing any other work. All gates shall be locked when not in use and shall bear a sign denoting danger.

7. Setbacks: Engineered grading sites may be required to have a peripheral area a maximum of seventy five feet (75') in width which shall be retained in its natural topographic condition. The setback area shall be used for, but is not limited to, access roads, planting, fencing, landscaped berms for screening purposes, employee and visitor parking, offices, directional signs and business signs identifying the occupant. (Ord. 2820, 1-14-1974, eff. 1-19-1974; Ord. 5526, 2-1-2010)

8. Contractors: During construction, flow control best management practices shall be protected consistent with the Surface Water Design Manual. (Ord. 5828, 12-12-2016)

I. REGULAR GRADING REQUIREMENTS:

1. Inspection, Testing and Reports: Inspection and testing by an approved testing agency including certification of the excavated or filled areas may be required by the Building Division at any time the City’s authorized inspectors believe problems may occur. Should special problems be indicated in regular grading, the Building Division may require the owner or operator to submit engineering reports similar to engineered grading and may specify a time period for compliance to prevent undue hazard. (Ord. 5526, 2-1-2010)

J. WORK IN PROGRESS:

1. Maximum Slopes – Work in Progress: No slopes greater than one horizontal to one vertical will be permitted for cuts, fills, or during excavations that exceed ten feet (10') in height without physical restraint by timbering or approval by the Community and Economic Development Department of an engineering or geologist report assuring slope will maintain its shape without undue risk of failing. (Ord. 2820, 1-14-1974, eff. 1-19-1974; Amd. Ord. 3592, 12-14-1981; Ord. 4835, 3-27-2000)

2. Safety: Workmen shall be allowed in the vicinity of the toe or top of slope only after close visual inspection of slope to assure safety against breakage or sliding.

3. Clearing and Rounding Tops of Slopes: All trees, timber, stumps, brush or debris shall be cleared to a point at least ten feet (10') back from the top of any slope involving cuts greater than ten feet (10'); provided, that exceptions may be granted in areas where trees and brush have a significant role in maintaining slope stability. After excavation, the top of all slopes shall be rounded to prevent a sheer breaking point.

4. Property and Setback Location: Property location and approved setbacks must be established and stakes set under the supervision of a registered land surveyor. These stakes must be maintained in place until final inspection of work so that the inspector can determine at any time if the excavation is properly located as related to the property lines.

5. Maximum Noise Levels: Noise levels at all operations shall be controlled to prevent undue nuisance to the public. Maximum allowable daytime sound pressure as measured in any residential zone shall not exceed the following at least ninety percent (90%) of the time between the hours of seven o’clock (7:00) a.m. and eight o’clock (8:00) p.m.

SOUND PRESSURE LEVELS

FREQUENCY
BAND IN
CYCLES/SECOND

SOUND PRESSURE LEVEL IN DECIBELS re. 0.0002 MICROBAR

25 – 300

80

 300 – 2,400

70

Above 2,400

60

(Ord. 2820, 1-14-1974, eff. 1-19-1974)

6. Permitted Work Hours: All mining, excavation and grading work done in residential areas or within three hundred feet (300') of residential areas shall be between the hours of seven o’clock (7:00) a.m. and eight o’clock (8:00) p.m., Monday through Friday, except repairs to machinery. Work may be permitted on Saturdays and Sundays only if approved in writing in advance by the Administrator. The Administrator is authorized to grant an extension of working time during an emergency. An emergency shall include but is not limited to natural and manmade disasters. (Ord. 3592, 12-14-1981, Amd. Ord. 4703, 2-2-1998)

7. Compliance with Pollution Control Regulations: Discharge of materials into the air or water shall be subject to the requirements of the appropriate governing agency. (Ord. 2820, 1-14-1974, eff. 1-19-1974)

8. Control of Dust and Mud: Activities shall be operated so as to reduce dust and mud to a minimum. Unless otherwise specified by the Public Works and Community and Economic Development Departments, operations shall be conducted in accordance with the following standards:

a. Access Roads: Access roads shall be maintained in a condition that confines the mud and dust to the site. Such roads shall be improved to a width sufficient to permit the unhindered movement of emergency vehicles. One-way roads shall have bypass routes to permit the movement of emergency vehicles.

b. Dozing and Digging: Dozing, digging, scraping and loading of excavated materials shall be done in a manner which reduces to the minimum level possible the producing of dust and mud. (Ord. 2820, 1-14-1974, eff. 1-19-1974, Amd. Ord. 3592, 12-14-1981)

9. Soil Erosion and Sedimentation: Soil erosion and sedimentation shall be confined to the site by such means as a temporary cover of vegetation, mulches, diversions, sedimentation ponds or other acceptable methods. No toxic materials shall be allowed to wash from the site or be discharged into receiving watercourses. (Amd. Ord. 4963, 5-13-2002)

10. Appearance: All activities under the jurisdiction of this Section shall be operated and maintained in a neat and orderly manner, free from junk, trash, or unnecessary debris. Buildings shall be maintained in sound conditions, in good repair and appearance. Salvageable equipment stored in a nonoperating condition shall be suitably screened or garaged. Landscaping adjacent to and around the main entrance(s) and office shall be sufficiently watered and cared for to insure its health and well-being. (Ord. 5526, 2-1-2010)

11. Soil Compaction: After grading, permeability of soils shall be reestablished in areas intended for stormwater management and infiltration or areas not required to have a structural capacity such as future lawn and open space areas. Techniques may include deep-tilling and loosening soils compacted during site grading in order to restore their natural infiltration capacity. (Ord. 5828, 12-12-2016)

K. SURFACE WATER:

1. Polluted or Stagnant Water Prohibited: Under no circumstances shall stagnant or polluted waters be permitted in any site. Should these waters accumulate, remedial measures such as draining or backfilling shall be taken as corrective action. Backfill material shall be placed to a point one foot above the water table.

2. Minimum Lake Depth: Lakes formed in areas which may be used for recreational purposes shall be of such depth that shall inhibit the growth of vegetative matter in the water. A minimum two foot (2') depth of water shall be maintained in these areas. The restoration of any site which results in the formation of a lake shall be the result of careful planning and shall take into consideration all factors which contribute to the ultimate ecology of the site.

3. Maximum Bank Slopes Adjacent to Lake: All banks, adjacent to any body of water created, shall be sloped or stepped as follows to permit a person to escape from the water:

a. Unconsolidated Material: Soil, sand, gravel and other unconsolidated materials shall be sloped to two feet (2') below the low groundwater line at a slope no steeper than one and one-half feet horizontal to one foot vertical (1.5':1'). (Ord. 5526, 2-1-2010)

L. TOP AND TOE SETBACKS:

1. Setbacks – Minimum: The tops and toes of cut and fill slopes shall be set back from setback lines as far as necessary to preserve the setback for the safety and benefit of adjacent properties, the adequacy of foundations, and to prevent damage as a result of water runoff or erosion of the slopes.

Setbacks shall be no less than the following:

a. Tops of Slopes: Distance to the setback line for the top of slopes shall be a minimum of ten feet (10').

b. Structures: Distance to structures, if any structures on the site shall be as follows:

Slope Height

Top

Toe

Less than 11'

5'

3'

11 – 30.9'

7'

Height/2'

31' and over

10'

15'

(Ord. 5526, 2-1-2010)

M. CUTS:

1. General: Unless otherwise recommended in the approved soil engineering and/or engineering geology report, cuts shall conform to the provisions of this Section.

2. Maximum Slope: The slope of cut surfaces shall be no steeper than is safe for the intended use. Except in conjunction with a modification granted per RMC 4-9-250D1 for one of the circumstances listed in RMC 4-3-050N2a(ii) (Geologic Hazards – Modifications), cut operations associated with a plat, short plat, subdivision or dedication, or other permitted land development activity which would result in the creation of permanent slopes forty percent (40%) or greater which are fifteen feet (15') in height, i.e., protected slopes, shall not be approved. (Amd. Ord. 4835, 3-27-2000)

3. Drainage and Terracing: Drainage and terracing shall be provided as required by subsection N of this Section.

(Ord. 5526, 2-1-2010)

N. FILLS:

1. Applicability and Exemptions: Unless otherwise recommended in the approved soil engineering report, fills shall conform to the provisions of this Section. In the absence of an approved soil engineering report, these provisions may be waived for minor fills not intended to support structures. For minor fills or waste areas, humps, hollows or water pockets shall be graded smooth with acceptable slopes.

2. Fill Location: Fill slopes shall not be constructed:

a. On natural slopes steeper than two-and-one-half horizontal to one vertical (2.5:1) that are fifteen feet (15') or greater in height (except in conjunction with a modification granted per RMC 4-9-250D1 for filling against the toe of a natural rock wall – see RMC 4-3-050N2a(ii)(b)); or

b. Where the fill slope toes out within twelve feet (12') horizontally of the top of existing or planned cut slopes that are fifteen feet (15') or greater in height and steeper than two-and-one-half horizontal to one vertical (2.5:1). (Amd. Ord. 4835, 3-27-2000; Ord. 4851, 8-7-2000)

3. Preparation of Ground: The ground surface shall be prepared to receive fill by removing vegetation, noncomplying fill, topsoil and other unsuitable materials as determined by the soil engineer, and where the slopes are five to one (5:1) or steeper, by benching into sound bedrock or other competent material, provided native vegetation and significant trees are protected pursuant to RMC 4-4-130. (Ord. 5828, 12-12-2016)

4. Fill Material: Fill material shall be subject to the following standards and requirements:

a. General: Fill materials shall have no more than minor amounts of organic decomposable substances and shall have no rock or similar irreducible material with a dimension greater than eight inches (8"). Material used in fills shall be appropriate for the site and the intended use of that portion of the site.

b. Construction, Demolition, and Land Clearing Waste Prohibited: Fill material shall be free of construction, demolition, and land clearing waste except that this requirement does not preclude the use of recycled concrete rubble from a Washington State Department of Transportation approved source.

c. Cleanliness of Fill Material: Fill material shall not contain concentrations of contaminants that exceed cleanup standards for soil specified in WAC 173-340-740, Model Toxics Control Act. No solid waste, hazardous waste, hazardous material, or materials categorized as dangerous waste under WAC Title 173 shall be used as fill.

d. The Administrator may specify other characteristics of the fill material used, the degree of compaction, the moisture content, and the method of placement based on the intended use of the portion of the site where the fill will be placed and the requirements for water retention, drainage control, and erosion control.

e. Fill Material Source Statement for Projects Located in Zone 1 of the Aquifer Protection Area Involving the Placement of More than Fifty (50) Cubic Yards of Imported Fill: A fill material source statement is required for projects located in Zone 1 of the Aquifer Protection Area if more than fifty (50) cubic yards of imported fill will be used; the documentation shall be certified by a professional engineer or geologist licensed in the State of Washington. The fill material source statement shall be provided to the Department and shall be reviewed and accepted by the Department prior to stockpiling or grading imported fill at the project site. The fill material source statement, as defined in RMC 4-8-120D19, shall be required for each source location from which imported fill will be obtained.

f. Fill Material Source Statement for Projects Located in Zone 2 of the Aquifer Protection Area Involving Placement of More than One Hundred (100) Cubic Yards of Imported Fill: A fill material source statement is required for projects located in Zone 2 of the Aquifer Protection Area if more than one hundred (100) cubic yards of imported fill will be used; the documentation shall be certified by a professional engineer or geologist licensed in the State of Washington. The fill material source statement shall be reviewed and accepted by the Department prior to stockpiling or grading imported fill at the project site. The fill material source statement, as defined in RMC 4-8-120D19, shall be required for each source location from which imported fill will be obtained.

g. Abbreviated Source Statement for Aquifer Protection Area: The Department may accept a fill material source statement, as defined in RMC 4-8-120D19, that does not include results of sampling and analysis of imported fill if a professional geologist or engineer licensed in the State of Washington certifies that the source location from which fill will be obtained has never been filled, developed, or subjected to use that could have introduced chemical contamination to the site.

h. Department Authority to Request Additional Information or Reject Certified Source Statement: The Department has the authority to request additional information regarding imported fill material and the source thereof and to reject a fill material source statement or an abbreviated version if they do not demonstrate that the fill material to be imported to a project site meets fill material standards of this Section and/or the Department has reason to suspect that the fill material could be contaminated. Such requests or rejections shall be made in writing to the applicant.

i. Source Statement Not Required for Imported Fill Obtained from Washington State Department of Transportation Approved Source: The source statement defined in RMC 4-8-120D19 is not required for those projects located in the aquifer protection area if documentation is provided that imported fill will be obtained from a Washington State Department of Transportation approved source. (Amd. Ord. 4851, 8-7-2000)

j. Sampling and Analysis Procedures: The licensed professional engineer or geologist or person under their supervision who samples earth materials to be used as imported fill, oversees analysis, and prepares a fill material source statement required by this Section shall follow procedures specified in WAC 173-340-820 and 173-340-830 of the Model Toxics Control Act – Cleanup regulations.

k. Required Actions after Illegal Placement of Imported Fill: A person who stockpiles or grades imported fill at the site without Department review and acceptance of a fill material source statement required by this Section or who stockpiles or grades fill at the site that does not meet the fill quality standards of this Section is subject to measures specified by the Department to reduce risk of contamination of the site due to illegal placement of fill. Such measures may include, but are not limited to, any or all of the following and shall be implemented at the person’s expense:

i. Provide the Department with a fill material source statement defined in RMC 4-8-120D19 within a time period specified by the Department;

ii. Immediately cover fill with a waterproof cover;

iii. Immediately remove fill;

iv. Installation of monitoring wells and monitoring of ground water quality;

v. Remediation of contamination of the site caused by the illegal placement of fill according to a schedule specified by the Department and in accordance with cleanup standards for soil and groundwater described in the Model Toxics Control Act – Cleanup regulations, chapter 173-340 WAC.

l. Department Authority to Conduct Independent Sampling and Analysis: The Department shall have the authority to enter onto private property to conduct independent sampling and analysis of fill. If the Department determines that fill does not meet fill quality standards of this Section, then it may require the person to accomplish any or all of the measures listed in this Section at his or her own expense.

m. Department Authority to Implement Removal and Remediation Measures: The Department or its authorized agents shall have the authority to implement measures listed in this Section if the person fails to accomplish such measures in a timely manner. The permittee shall be responsible for any costs incurred by the Department or its authorized agents in the conduct of such activities. (Amd. Ord. 4740, 7-19-1999; Ord. 4992, 12-9-2002; Ord. 5954, 11-18-2019)

5. Minimum Compaction: All fills shall be compacted to a minimum of ninety five percent (95%) of maximum density as determined by American Public Works Association (APWA) specifications. Field density shall be determined in accordance with APWA standards. Exceptions to the compaction requirement include soils below areas set aside for low impact development best management practices designed consistent with RMC 4-6-030. (Ord. 5828, 12-12-2016)

6. Maximum Slope: The slope of fill surfaces shall be no steeper than is safe for the intended use. Except in conjunction with a modification granted per RMC 4-9-250D1 for one of the circumstances listed in RMC 4-3-050N2a(ii) (Geologic Hazards – Modifications), fill operations associated with a plat, short plat, subdivision or dedication, or other permitted land development activity which would result in the creation of permanent slopes forty percent (40%) or greater which are fifteen feet (15') in height, i.e., protected slopes, shall not be approved. (Amd. Ord. 4835, 3-27-2000)

7. Drainage and Terracing: Drainage and terracing shall be provided and the area above fill slopes and the surfaces of terraces shall be as required by subsection N of this Section. (Ord. 5526, 2-1-2010)

O. SOLID WASTE FILLS:

1. Reports Required: Reports by an engineer qualified in solid and sanitary waste fills shall be required. Such reports shall include but are not limited to design; insect and vermin control, physiological considerations; sight, noise and odor control of material; special ingress and egress control for equipment; and special drainage requirements. These reports shall be in addition to those required elsewhere in this Section.

2. Report Contents: The engineering reports submitted shall include plans and means of preventing and eliminating any health hazards and visual problems. All phases of sanitary landfill operations and solid waste fills shall be provided in the engineering report, including type, nature, and amount of equipment, manpower, special precautions, chemical usage and availability of granular material for the coverage of the cell material. Bonding requirements, restrictions on noise, dust and mud, special fencing requirements, special precautions required and availability of twenty four (24) hour inspection and correction of hazards shall be provided by operator agreement with the City prior to any consideration for either a sanitary landfill or solid waste fill.

3. General: Unless specific requirements are mentioned in this Section, the requirements of subsection L of this Section shall be followed.

4. Location: Special attention shall be given to solid waste and/or sanitary fill location to prevent undue hazard.

5. Cell Cover: Cell construction on any solid waste fill shall consist of at least a six inch (6") noncontaminated uniformly graded granular cover material covering the entire area of the cell construction. Each cell shall be covered the same day it is constructed.

6. Compaction: Compaction of the solid waste or sanitary fill material and mixture of the material shall be such as to provide a relatively uniform density with no extreme soft spots. Density of compacted cellular solid waste material shall be as high as possible in accordance with good mixing compacting standards and shall at no time be less than forty percent (40%) of the density of a similar sample of material compacted under ideal conditions by providing a fifty (50) pound per square foot surcharge on a one cubic foot sample of the material.

7. Bulk Items: Solid waste materials of bulk items involving metallic units similar to refrigerators, stoves, car bodies, water tanks, heavy timber items and similar items shall be placed in the lower portion of a cell with sufficient cover and compaction of cover to preclude any dangerous voids.

8. Building Debris and Flammable Material: Broken wood, building material and related debris from structure removal (exclusive of brick and concrete) shall be satisfactorily broken and crushed to provide a reasonably compacted cell when covered by granular material. Protection shall be provided for any wood or burnable material to prevent fire either on the surface or subsurface. The earth cover on any cell containing flammable material including paper, wood, or vegetable products shall be sufficiently covered to prevent spread of flames should combustion occur in any cell due to spontaneous combustion.

9. Stabilization: Brick, broken concrete, crushed building materials, not including extensive wooden or flammable matter, may be utilized in embankment where they may be of assistance in preventing undue sliding, water scouring or voids which might harbor vermin. This material shall be sufficiently mixed or covered with suitable granular material to prevent unsightly effects.

10. Animal Waste: Animal waste shall be provided with suitable cover and sterilization to prevent decay odors, build up of flammable gasses, or possible leaching of putrescible material. Chemical treatment shall be provided to prevent insect habitation.

11. Treated Fill: Materials such as hay, straw, tree limbs and brush, vegetable farm waste, feathers, rubber tires, wood pulp, chemical substances, industrial waste, and silage type material may need special treatment before utilization in a solid waste or sanitary landfill. Special request and reports shall be made on waste materials of the foregoing types prior to placement in landfills.

12. Prohibited Fill: No materials of appreciable volume of an extremely harmful nature to environment shall be placed in any solid waste or sanitary landfill. This includes, but is not limited to, any form of demolition material of an explosive nature, any volatile or liquid petroleum product, any chemical salts or soluble material which would contaminate stormwater, surface water or air, and any animal meat or semisolid fruit or grain products which might become rancid, putrescible or harmful. No provisions of the sanitary landfill or solid waste fill requirements shall preclude the use of nonharmful native clay, sand, rock, or normal fill type materials in filling operations covered under other subsections of this Section.

13. Drainage: Special attention shall be provided drainage in any solid waste or sanitary landfill to prevent leaching of noxious or putrescible materials, decaying nuisance, any contamination of normal watercourses. Where water might leach through the construction cells, subdrains, lateral collectors and storage ponds shall be provided. Leach water from solid waste shall not be permitted to percolate downward into the water table. Leach water shall be collected and conveyed to a sewage treatment plant.

14. Water Disposal: Any leach water coming from covered sanitary or solid waste fill cells shall be collected, stored and decontaminated by suitable chemical or other means and then disposed of in a sanitary sewer. Should suitable collection facilities, sand filters and chemical-cleaning be provided to prevent any toxicity and reduce the leach water to an equivalent of normal storm flow, the Public Works Department may permit disposal through normal stormwater facilities. Frequent samples of all water collected shall be taken, and flow conditions shall be controlled to prevent contamination or overloading of either the sanitary or stormwater facilities. Surface runoff in any sanitary pit or solid waste landfill shall be maintained separately to prevent contamination by leaching.

15. Special Considerations: Special paving, surface protection, and related health requirements may be imposed on sanitary landfill and solid waste operations.

16. Prohibited Activities: No junk picking or field salvaging of any solid waste or sanitary landfill items shall be allowed in the vicinity of the landfill. Any separation of materials for salvage shall be provided at the collection point or an approved transfer site prior to disposal at the landfill site. (Ord. 5526, 2-1-2010)

P. DRAINAGE:

1. General: Unless otherwise indicated on the approved grading plan, drainage facilities and terracing shall conform to the provisions of this Section. Special drainage protection work may be ordered in case of emergency or serious potential flooding conditions, and the grading operator required to have available an employee to be called in times of potential serious emergency hazards.

2. Terrace: Terraces at least eight feet (8') in width shall be established at no more than twenty five foot (25') intervals to control surface runoff. Suitable access shall be provided to permit cleaning and maintenance.

a. Swales: Swales or ditches on the back side of the terrace shall have a maximum longitudinal gradient of two percent (2%) unless protected by special paving, use of corrugated metal or other scour prevention devices. Drainage shall be designed to minimize trapping of excessive water which might endanger the terrace. Terraces shall slope toward the back or cut face at a minimum of ten percent (10%) slope to keep water from overtopping.

b. Scouring: Single run of swale or ditch shall not collect runoff from a tributary area exceeding thirteen thousand five hundred (13,500) square feet of the area of the face of the slope without discharging into a down drain. Down drains shall terminate into a catch basin or other approved receiver to prevent scouring at the outfall.

c. Capacity: Designed capacity for terraces shall be a twenty four (24) hour, twenty five (25) year storm as published by the U.S. Weather Bureau. Design velocity shall be such as to avoid water transporting colloidal silts in the stream. Should request be made for variation from the twenty four (24) hour, twenty five (25) year storm by the engineering designer, sufficient data shall be submitted in an engineering report to analyze the requested variation. When accumulated flows are such that the water is capable of transporting colloidal silts or other particles in suspension down drains, pipe or lined ditches shall be incorporated to dispose of the runoff safely. Energy dispersing structures shall be used to prevent erosion.

d. Settling Ponds: Where stormwater and ground conditions appear to warrant, special holding and settling ponds, stormwater storage reservoirs, or other means may be required to prevent overload or unusual by-pass of storm flow water to areas off the owner’s site and control.

3. Subsurface Drainage: Cut and fill slopes shall be provided with subsurface drainage as necessary for stability.

4. Disposal: All drainage facilities shall be designed to carry waters to the nearest practicable drainage way approved by the City and/or other appropriate jurisdiction as a safe place to deposit such waters. Silt and other debris shall be removed prior to the disposal of such water. If drainage facilities discharge onto natural ground, riprap may be required. (Ord. 2820, 1-14-1974, eff. 1-19-1974)

a. Minimum Grade: At least two percent (2%) gradient toward approved drainage facilities from building pads will be required unless waived by the Building Department for nonhilly terrain. Exception: The gradient from the building pad may be one percent (1%) where building construction, and erosion control will be completed before hazardous conditions can occur. (Ord. 2820, 1-14-1974, eff. 1-19-1974; Amd. Ord. 3592, 12-14-1981)

b. Drainage Releases: The property owner or his authorized agent shall submit acceptable copies of drainage releases from downstream owners or other government agencies concerned whenever drainage is interrupted, diverted or changed from natural surface or subsurface drainage patterns.

c. Stream Acceptance: The volume and rate of water released shall not exceed the receiving stream’s or watercourse’s ability to accept the water without erosion.

5. Overland Runoff: Runoff from areas of higher elevation shall be safely routed around or through the extraction or fill area. (Ord. 2820, 1-14-1974, eff. 1-19-1974; Ord. 5526, 2-1-2010)

Q. SLOPES:

1. General: The faces of cut and fill slopes shall be provided and maintained to control against erosion. This control may consist of effective planting. The protection for the slopes shall be installed as soon as practicable and prior to calling for final approval. Where cut slopes are not subject to erosion due to the erosion-resistant character of the materials, such protection may be omitted with the permission of the Building Department, provided that this protection is not required by the rehabilitation plan. (Ord. 2820, 1-14-1974, eff. 1-19-1974; Amd. Ord. 3592, 12-14-1981)

2. Other Devices: Where necessary check dams, cribbing, riprap or other devices or methods shall be employed to control erosion and sediment, provide safety, and control the rate of water runoff. (Ord. 2820, 1-14-1974, eff. 1-19-1974; Ord. 5526, 2-1-2010)

R. FINAL REPORTS:

1. Construction Timing and Final Approval:

a. No work related to permanent or temporary storm drainage control for a permitted development may proceed without the approval of the Administrator.

b. Erosion and sediment control measures associated with both the interim and permanent systems shall be:

i. Constructed in accordance with the approved plan prior to any grading or land clearing other than associated with an approved erosion and sediment control plan; and

ii. Satisfactorily sequenced and maintained until all improvements, restoration and landscaping associated with the permit and approvals for the project are completed and the potential for on-site erosion has passed.

2. Plans and Reports: Upon completion of the rough grading work and at the final completion of the work, the Development Services Division may require the following reports and drawings and supplements thereto: (Ord. 2820, 1-14-1974, eff. 1-19-1974; Amd. Ord. 3592, 12-14-1981)

a. As-Graded Grading Plan: An as-graded grading plan prepared by the civil engineer including original ground surface elevations, as-graded ground surface installations, lot drainage patterns and locations and elevations of all surface and subsurface drainage facilities. The civil engineer shall provide certification that the work was done in accordance with the final approved grading plan.

b. Soil Grading Report: A soil grading report prepared by the soil engineer including locations and elevations by field density tests, summaries of field and laboratory tests and other substantiating data and comments on any changes made during grading and their effect on the recommendation made in the soil engineering investigation report. The soil engineer shall provide certification as to the adequacy of the site for the intended use.

c. Geologic Grading Report: A geologic grading report prepared by the engineering geologist including a final description of the geology of the site including any new information disclosed during the grading and the effect of same on recommendations incorporated in the approved grading plan. The engineering geologist shall provide certification as to the adequacy of the site for the intended use as affected by geologic factors. (Ord. 2820, 1-14-1974, eff. 1-19-1974)

3. Notification of Completion: The permittee or his agent shall notify the Development Services Division when the grading operation is ready for final inspection. (Ord. 2820, 1-14-1974, eff. 1-19-1974; Amd. Ord. 3592, 12-14-1981; Ord. 5526, 2-1-2010)

4. Final Approval: The applicant shall construct and have in operation those portions of the drainage facilities necessary to accommodate the control of surface and stormwater runoff discharging from the site (a) before the construction of any other improvements or buildings on the site, and (b) prior to final recording of a plat or short plat. However, upon written request and provision for security acceptable to the City, the Administrator may authorize a delay in the construction of drainage facilities beyond other construction and/or recording if such delay would minimize adverse drainage impacts related to weather and/or soil conditions. Final approval shall not be given until all work including installation of all drainage facilities and their protective devices and all erosion control measures have been completed in accordance with the final approved grading plan and the required reports have been submitted. (Ord. 5828, 12-12-2016)

S. PERMITS AND FEES REQUIRED:

1. Submittal Requirements and Fees: Grading, excavation and mining permits and licenses are required per RMC 4-9-080 for major and minor activities. Submittal requirements are listed in RMC 4-8-120, Submittal Requirements – Specific to Application Type. Application fees are listed per Chapter 4-1 RMC, Administration and Enforcement.

2. Threshold for Drainage Review: A person applying for a grading, excavation and mining permit and license shall be required to comply with all drainage review requirements per RMC 4-6-030 if the project results in seven thousand (7,000) square feet or more of land disturbing activity.

3. Plans and Calculations Required: Submittal of plans and supportive calculations shall be in accordance with RMC 4-6-030. (Ord. 4963, 5-13-2002; Ord. 5526, 2-1-2010)

T. APPEALS:

If the applicant does not concur with the requirements of the Development Services Division, he has the prerogative of appealing to the Hearing Examiner pursuant to RMC 4-8-110. (Ord. 3592, 12-14-1981; Amd. Ord. 4963, 5-13-2002; Ord. 5526, 2-1-2010)

U. VIOLATIONS OF THIS CHAPTER AND PENALTIES:

Unless otherwise specified, violations of this Chapter are misdemeanors subject to RMC 1-3-1. (Ord. 4351, 5-4-1992; Amd. Ord. 4963, 5-13-2002; Ord. 5159, 10-17-2005; Ord. 5526, 2-1-2010)