Colusa County Municipal Code Art. I Definitions and General Provisions

(Ord. No. 784 § 1 (Exh. A) (part))

The purpose of this chapter is to establish standards for the approval, installation, and operation of on-site wastewater treatment systems (OWTS) within Colusa County, consistent with plans, policies, and standards of the California State Water Resources Control Board and Central Valley Regional Water Quality Control Board (Regional Water Board). The standards are adopted to prevent the creation of health hazards and nuisance conditions and to protect surface and groundwater quality.

(Ord. No. 784 § 1 (Exh. A) (part))

This chapter is applicable to all existing and new OWTS in the unincorporated area of Colusa County having a wastewater design flow of ten thousand gallons per day (gpd) or less. If the amount of wastewater produced is more than ten thousand gpd, or if the wastewater system is dedicated to receiving significant amounts of wastes dumped from RV holding tanks, or where the wastewater system includes above-ground discharge of effluent (e.g., surface irrigation, percolation or evaporation pond), the method of treatment and dispersal must be approved by the Regional Water Quality Control Board. Notification will be provided to the Regional Water Quality Control Board and review comments solicited for: (a) any proposed OWTS with a projected daily wastewater flow of more than two thousand five hundred gallons per day; and (b) any proposed community OWTS serving multiple discharges under separate ownership. Where a governmental entity has entered into an agreement with the board of supervisors to assume responsibility for regulating or issuing permits to construct, alter, modify or replace OWTS, then the provisions of this chapter shall not apply within the jurisdictional limits of that entity for the scope of responsibility assumed by the entity.

(Ord. No. 784 § 1 (Exh. A) (part))

The director of the environmental health division or his/her assign(s), on behalf of the county's health officer, shall administer and enforce all provisions of this chapter relative to installation, maintenance, operation and abandonment of OWTS, including but not limited to septic tanks, cesspools, holding tanks, supplemental wastewater treatment systems, subsurface dispersal systems or other matters regulated or provided in this chapter not expressly delegated to some other department or agency.

(Ord. No. 784 § 1 (Exh. A) (part))

The county, its officers, agents and employees are not liable or responsible for damage resulting from the defective construction of any OWTS as herein provided, nor will the county or any official or employee thereof be liable or responsible by reason of any inspection authorized hereunder.

(Ord. No. 784 § 1 (Exh. A) (part))

(a) The director is authorized to issue standards and guidelines, including policies, procedures and technical details, to carry out the purposes of this chapter, which shall be contained in a document titled the Onsite Systems Manual.

(b) The Onsite Systems Manual shall be developed, maintained and amended as necessary by the director and shall provide a reasonable process for seeking input from the affected public and OWTS practitioners in connection with its development and when changes are made.

(c) The Onsite Systems Manual and any amendments shall be subject to approval by the Regional Water Board in accordance with applicable state requirements and policies for OWTS.

(d) The type and manner of design and construction of OWTS shall conform to the standards as required by this chapter and the Onsite Systems Manual.

(e) The director shall maintain records pertaining to the permitting, installation, inspection, repairs and variances issued in regard to OWTS and prepare and submit applicable reports and information to the Regional Water Quality Board in accordance with provisions of the state OWTS policy.

(Ord. No. 784 § 1 (Exh. A) (part))

(a) The following terms used in this chapter have the same definition as in the state OWTS policy, which is available on the Colusa County environmental health division’s website: basin plan, beneficial uses, cesspool, domestic wastewater, groundwater, major repair, on-site wastewater treatment system (OWTS), qualified professional, Regional Water Quality Control Board, replacement OWTS, seepage pit, septic tank, site evaluation, soil, supplemental treatment, and waste discharge requirements (WDR).

(b) The following terms used in this chapter are defined as follows:

(1)

“Alternative OWTS”

means any OWTS that does not meet the criteria of a conventional OWTS, but is allowed under conditions prescribed in this chapter and approved by the director.

(2)

“Community system”

means an OWTS that provides for the collection, treatment and dispersal of wastewater from multiple discharges under separate ownership.

(3)

“Conventional OWTS”

is a type of OWTS consisting of a septic tank for primary treatment of sewage followed by a system of dispersal trenches for subsurface dispersal of effluent into the soil. A conventional OWTS may utilize gravity flow or a pump system to convey effluent from the septic tank to the drainfield.

(4)

“Cumulative impacts”

means the persistent and/or increasing effect of OWTS resulting from the density of such discharges in relation to the assimilative capacity of the local environment. Examples include, but are not limited to: (A) nitrate or salt additions to groundwater or surface water; and (B) rise in groundwater levels (“mounding of the water table”) that interferes with the performance of an OWTS, causes drainage problems or results in other adverse hydrological or soil conditions affecting public health, water quality or public safety.

(5)

“Department”

means the Colusa County department consisting of the planning and building units and the environmental health division.

(6)

“Director”

means the director of the environmental health division or his or her designated representative acting on behalf of the County of Colusa’s health officer.

(7)

“Dispersal system”

means a series of trenches, beds, subsurface drip lines, or other approved method for subsurface infiltration and absorption of wastewater effluent, including all component parts, such as piping, valves, filter material, chambers, dosing pumps, siphons and other appurtenances.

(8)

“Failure”

means the ineffective treatment and dispersal of waste resulting in the surfacing of raw or inadequately treated sewage effluent and/or the degradation of surface or groundwater quality.

(9)

“Hearing officer”

means the person or body authorized by the board of supervisors to conduct hearings under the provision of this chapter.

(10)

“Holding tank”

means a watertight receptacle used to collect and store wastewater prior to it being removed from a property by means of vacuum pumping and hauling, or other approved method. The use of holding tanks in Colusa County is authorized for limited circumstances, including, but not limited to, for the abatement of health hazards or for certain public use facilities.

(11)

“Installation permit”

means a document issued by the director that conveys approval of and sets forth applicable conditions for the installation of an OWTS, or component thereof.

(12)

“Onsite Systems Manual”

means the document developed, maintained, and amended by the Colusa County environmental health division containing policy, procedural and technical details for implementation of this chapter, as prescribed by the director and approved by the Regional Water Board.

(13)

“On-site wastewater maintenance provider”

means a person capable of operating, monitoring and maintaining an OWTS in accordance with the requirements of this chapter, and possessing minimum experience and qualifications as established by the director in the Onsite Systems Manual.

(14)

“On-site wastewater treatment system” or “OWTS”

means a system of pipes, tanks, trenches and other components used for the collection, treatment and subsurface dispersal of domestic wastewater at or near the building or buildings being served. The short form of the term may be singular or plural. For the purposes of this chapter, OWTS do not include “gray water” systems pursuant to Health and Safety Code Section 17922.12. Wastewater systems that discharge effluent above ground (e.g., via surface irrigation, percolation/evaporation pond) are not covered within the definition of an OWTS and are not authorized under this chapter.

(15)

“Operating permit”

means the administrative document issued by the director authorizing the initial and/or continued use of an alternative OWTS in conformance with the provisions of this chapter, intended to aid in verification of the adequacy of alternative OWTS performance, and that may contain both general and specific conditions of use. An operating permit may also be issued for circumstances other than alternative OWTS, such as in connection with holding tank exemptions or where, in the opinion of the director, the type, size, location or other aspects of a particular OWTS installation warrant the additional level of oversight provided by an operating permit.

(16)

“Registered septic tank pumper”

means a person with an active liquid waste pumper permit issued by the director in accordance with California Health and Safety Code, Division 104, Part 13, Sections 117400 through 117450, as qualified to pump and haul septic tank sludge (“septage”).

(17)

“Sanitary sewer”

means a system for collecting residential or municipal wastewater and directing the collected wastewater to a treatment works prior to dispersal.

(18)

“Site evaluation”

means an assessment of the characteristics of the site sufficient to determine its suitability for an OWTS to meet the requirements of this chapter. Site evaluations shall be in accordance with procedures and criteria established by the director and contained in the Onsite Systems Manual.

(19)

“Sewage” or “sewage effluent”

means waste as defined in Section 5410(a), California Health and Safety Code.

(20)

“State OWTS policy”

means the Water Quality Control Plan for Siting, Design, Operation and Maintenance of Onsite Wastewater Treatment Systems adopted by the State Water Resources Control Board on June 19, 2012, which became effective May 13, 2013.