Chapter 6.08
PRETREATMENT OF WASTEWATER

Sections:

6.08.010    Pretreatment facilities.

6.08.020    Additional pretreatment measures.

6.08.030    Accidental discharge/slug discharge control plans.

6.08.040    Bypass.

6.08.050    Hauled wastewater.

6.08.010 Pretreatment facilities.

Users shall provide wastewater treatment as necessary to comply with this division and shall achieve compliance with all categorical pretreatment standards, local limits, and the prohibitions set out in WMWDC 6.04.010 within the time limitations specified by EPA, the state, or the general manager, whichever is more stringent. Any facilities necessary for compliance shall be provided, operated, and maintained at the user’s expense. Detailed plans describing such facilities and operating procedures shall be submitted to the general manager for review, and shall be acceptable to the general manager before such facilities are constructed. The review of such plans and operating procedures shall in no way relieve the user from the responsibility of modifying such facilities as necessary to produce a discharge acceptable to Western under the provisions of this division. (Ord. 387 § 4.1, 2017)

6.08.020 Additional pretreatment measures.

A. Whenever deemed necessary, the general manager may require users to restrict their discharge during peak flow periods, designate that certain wastewater be discharged only into specific sewers, relocate and/or consolidate points of discharge, separate sewage wastestreams from industrial wastestreams, and such other conditions as may be necessary to protect the collection system and POTW and determine the user’s compliance with the requirements of this division.

B. The general manager may require any user discharging into the POTW to install and maintain, on their property and at their expense, a suitable storage and flow control facility to ensure equalization of flow. An individual wastewater discharge permit may be issued solely for flow equalization.

C. Grease, oil, and sand interceptors shall be provided when, in the opinion of the general manager, they are necessary for the proper handling of wastewater containing excessive amounts of grease and oil, or sand; except that such interceptors shall not be required for residential users. All interception units shall be of a type and capacity approved by the general manager and shall be so located to be easily accessible for cleaning and inspection. Such interceptors shall be installed, cleaned, and repaired by the user at their expense. The use of chemicals or other materials including biological products which emulsify, suspend, or in any other manner, allow fats, oil and grease to pass through, rather than be retained by the interceptor is prohibited. (Ord. 387 § 4.2, 2017)

6.08.030 Accidental discharge/slug discharge control plans.

The general manager shall evaluate whether each SIU needs an accidental discharge/slug discharge control plan or other action to control slug discharges. The general manager may require any user to develop, submit for approval, and implement such a plan or take such other action that may be necessary to control slug discharges. Alternatively, the general manager may develop such a plan for any user. An accidental discharge/slug discharge control plan shall address, at a minimum, the following:

A. Description of discharge practices, including nonroutine batch discharges;

B. Description of stored chemicals;

C. Procedures for immediately notifying the general manager of any accidental or slug discharge, as required by WMWDC 6.14.060; and

D. Procedures to prevent adverse impact from any accidental or slug discharge. Such procedures include, but are not limited to, inspection and maintenance of storage areas, handling and transfer of materials, loading and unloading operations, control of plant site runoff, worker training, building of containment structures or equipment, measures for containing toxic organic pollutants, including solvents, and/or measures and equipment for emergency response. (Ord. 387 § 4.3, 2017)

6.08.040 Bypass.

A. For the purposes of this section:

1. “Bypass” means the intentional diversion of wastestreams from any portion of a user’s treatment facility.

2. “Severe property damage” means substantial physical damage to property, damage to the treatment facilities which causes them to become inoperable, or substantial and permanent loss of natural resources which can reasonably be expected to occur in the absence of a bypass. Severe property damage does not mean economic loss caused by delays in production.

B. A user may allow any bypass to occur which does not cause pretreatment standards or requirements to be violated, but only if it also is for essential maintenance to assure efficient operation. These bypasses are not subject to the provisions of subsections C and D of this section.

C. Bypass Notifications.

1. If a user knows in advance of the need for a bypass, it shall submit prior notice to the general manager at least 10 days before the date of the bypass.

2. A user shall submit oral notice to the general manager of an unanticipated bypass that exceeds applicable pretreatment standards within 24 hours of said event. A written submission shall also be provided within five days of the unanticipated bypass. The written submission shall contain a description of the bypass and its cause; the duration of the bypass, including exact dates and times, and, if the bypass has not been corrected, the anticipated time it is expected to continue; and steps taken or planned to reduce, eliminate, and prevent reoccurrence of the bypass. The general manager may waive the requirement of a written report on a case-by-case basis in his or her discretion.

D. Bypass.

1. Bypass is prohibited, and the general manager may take an enforcement action against a user for a bypass. The general manager’s decision on the enforcement action may take into account any of the following which may constitute mitigating factors:

a. Bypass was unavoidable to prevent loss of life, personal injury, or severe property damage;

b. There were no feasible alternatives to the bypass, such as the use of auxiliary treatment facilities, retention of untreated wastes, or maintenance during normal periods of equipment downtime. This condition will not be considered a mitigating factor if adequate back-up equipment should have been installed in the exercise of reasonable engineering judgment, to prevent a bypass which occurred during normal periods of equipment downtime or preventive maintenance; and

c. The user submitted notices as required under subsection C of this section.

2. The general manager may approve an anticipated bypass, after considering its adverse effects, if the general manager determines that it will meet the three conditions listed in subsection (D)(1) of this section. (Ord. 387 § 4.4, 2017)

6.08.050 Hauled wastewater.

A. Septic tank waste may be introduced into the POTW only at locations designated by the general manager and at such times as are established by the general manager. Such waste shall not violate Chapter 6.04 WMWDC or any other requirements established by WRCRWA. The general manager may require septic tank waste haulers to obtain individual wastewater discharge permits.

B. The general manager may require haulers of industrial waste to obtain individual wastewater discharge permits. The general manager may require generators of hauled industrial waste to obtain individual wastewater discharge permits. The general manager also may prohibit the disposal of hauled industrial waste. The discharge of hauled industrial waste is subject to all other requirements of this division.

C. Industrial waste haulers may discharge loads only at locations designated by the general manager. No load may be discharged without prior consent of the general manager. The general manager may collect samples of each hauled load to ensure compliance with applicable standards. The general manager may require the industrial waste hauler to provide a waste analysis of any load prior to discharge.

D. Industrial waste haulers must provide a waste tracking (manifest) form for every load. This form shall include, at a minimum, the name and address of the industrial waste hauler, permit number, truck identification, names and addresses of sources of waste, and volume and characteristics of waste. The form shall identify the type of industry, known or suspected waste constituents, and whether any wastes are RCRA hazardous wastes. (Ord. 387 § 4.5, 2017)