TITLE IV ONSITE WASTEWATER
MANAGEMENT CODE

CHAPTER 4.03 DEFINITIONS

Sections:

4.03.010  General
For the purpose of this code, certain terms, phrases, words and their derivatives shall be construed as specified in this chapter. Words used in the singular include the plural, and the plural the singular. Words used in the masculine gender include the feminine, and the feminine the masculine.

4.03.030  Terms Defined by Federal and State Agencies
Terms which are not specifically defined in this code shall be as defined in the Minimum Guidelines for the Control of Individual Wastewater Treatment & Disposal Systems of the California Regional Water Quality Control Board, San Francisco Bay Region (hereinafter referred to as Minimum Guidelines), Appendix A. Terms not defined in this code or in said Appendix A shall be as defined in the Glossary of the most recent edition of the Design Manual: Onsite Wastewater Treatment and Disposal Systems, (hereinafter referred to as Design Manual) and any subsequent revisions, published by the United States Environmental Protection Agency.

4.03.050  Other Sources of Definitions
Terms which are not defined in this code or the sources listed in 4.03.030, but which are defined in the most recently published version of the Uniform Plumbing Code (hereinafter referred to as Uniform Plumbing Code), as published by the International Association of Plumbing and Mechanical Officials, shall be construed as specified in that code. Additionally, terms which are not defined in this code or other sources prescribed above, but which are defined in the most recently published version of the Uniform Building Code as published by the International Conference of Building Officials, shall be construed as specified in that code.

4.03.090  Common Definition
Terms herein for which a definition is not otherwise prescribed either in this code or in other sources referred to herein shall have their ordinarily accepted meaning within the context in which they are used. Merriam Webster's Third New International Dictionary of the English Language, Unabridged, copyright 2002 or a successive publication shall be considered as providing ordinarily accepted meanings.

4.03.202  Alternative System
Alternative system shall mean a wastewater treatment system other than a standard septic system.

4.03.205  Change of Use
Change of use shall mean that either the quality and/or quantity of wastewater disposed in a wastewater treatment system has changed such that the existing system may be inadequate for the use.

4.03.207  Chemical Toilet
A chemical toilet is a temporary toilet which utilizes chemicals to mask odors.

4.03.212  Cut or Embankment
A cut or an embankment shall mean all cuts and embankments, whether or not retained by a structure, as defined in the Minimum Guidelines, which cut or embankment is greater than 24 inches (24") in vertical height.

4.03.215  Designer
A designer shall mean any person licensed, registered, or otherwise authorized by the State of California to design onsite wastewater systems.

4.03.216  Discharge Permit
Discharge permit shall mean a recorded document that authorizes operation of an onsite wastewater treatment system in accordance with this code.

4.03.217  District Engineer
The District engineer shall mean any engineer appointed pursuant to 4.05.020 whom the General Manager has deputized to act on his behalf to implement this code.

4.03.220  Downslope Property Line
Downslope property line shall mean a property line of the subject property where the ground on the adjacent property slopes downward from that property line.

4.03.224  Dispersal Field
Dispersal field shall mean a system of trenches or beds that distribute treated sewage effluent for absorption into the soil. "Soil absorption system" as used in the Minimum Guidelines, "disposal field" as used in the Uniform Plumbing Code, and "leach field" as commonly used shall be considered synonymous with dispersal field.

4.03.225  Drip Dispersal
Drip dispersal shall mean dispersal of high quality effluent for subsurface landscaping utilizing a non-clogging drip tube and non-clogging emitters.

4.03.226  Dual Dispersal Fields
Dual dispersal fields shall mean a wastewater treatment system that includes two complete dispersal fields connected by an accessible diversion valve and intended for alternating use.

4.03.227  Existing Use
Existing use shall mean that the quality and quantity of wastewater disposed in a wastewater treatment system is unchanged.

4.03.228  Failed System or Failed Wastewater Treatment System
Failed system and failed wastewater treatment system shall mean a wastewater treatment system which is discharging in violation of this code, or a wastewater treatment system whose components do not meet the specifications of this code.

4.03.229  Failed System Citation
FFailed System Citation is the District's primary tool for enforcement. A Failed System Citation is issued after a Discharge Permit has been revoked pursuant to Section 4.07.740, and the citation is recorded at the office of the Marin County Recorder.

4.03.230  Graywater
Graywater is untreated water which has not come into contact with toilet waste. Graywater includes used water from hot tubs, bathtubs, showers, bathroom wash basins, clothes washing machines and laundry tubs or an equivalent discharge. It does not include waste water from kitchen sinks, photo lab sinks, dishwashers or laundry water from soiled diapers.

4.03.231  Graywater System
Any onsite wastewater system design which conforms to 2013 California Plumbing Code (CPC), Chapter 16, Non-potable Water Reuse Systems shall be designated a graywater system.

4.03.231.1  Grease Interceptor or Grease Trap
An external, in-ground, watertight receptacle/chamber, designed and constructed to intercept fats, oils, and grease upstream of the septic tank and/or any supplementary treatment tank.

4.03.232  Groundwater
Groundwater shall mean any subsurface body of water.

4.03.237  Habitable Space
Habitable space shall mean space within a structure that is designed or useable for living, sleeping, eating, or cooking. Bathrooms, toilet compartments, closet, hall, storage, or utility space and similar areas are not considered habitable space, but will be included when calculating the total floor area under Section 4.15.621. Habitable space shall be measured from the interior walls in a residence or detached building.

Most space within a structure shall be deemed habitable space. Non-habitable space, however, will include rooms or enclosed spaces which do not have windows, are not connected to central heating or cooling, and are not designed and intended for human occupancy, including, but not necessarily limited to the following:

1. Garages used for vehicular parking or storage
2. Unfinished basements
3. Mechanical equipment rooms
4. Unimproved space that does not meet the minimum height standard for habitable space according to the California Building Code (CBC)
5. Stairwells, other than the ground floor landing for each stairwell (i.e., each stairwell only counted once)
6. Non-habitable accessory structures

4.03.244  Maintenance
Maintenance of a wastewater treatment system shall mean clearing of stoppages in pipes in nontreatment components; repairing or replacing non-treatment components of a wastewater system; pumping liquid and solids from, or otherwise cleaning septic tanks and grease traps; cleaning sand filters; and cleaning pressure distribution system pumps and piping.

4.03.248  M.P.N. - Most Probable Number
M.P.N. (most probable number) is an estimate of the actual number of colony-forming units based on established probability formulae. For further explanation, see Standard Methods for the Examination of Water and Wastewater.

4.03.252  New Construction
New construction shall mean the construction of a new building or building addition with habitable space. Further, the construction of any new structure within a setback from a component of a wastewater system required at the time the system was installed shall be deemed to be new construction.

4.03.258  Non-Treatment Component
Non-treatment component shall mean a component of an onsite wastewater treatment system that is not a treatment component. This includes, but is not limited to, risers, septic tank lids, tight lines, inlet T's, outlet T's, diversion valves, and non-perforated pipe.

4.03.258  Pretreatment Device
Pretreatment Device shall mean a treatment component, such as a sand filter, recirculating textile filter, or aerobic treatment unit which is designed to reduce contaminants in wastewater effluent prior to treatment and dispersal in the leach field.

4.03.264  Repair or Replacement
Repair or replacement shall mean the alteration, changing, repairing, or replacing of any part, component, or element of a wastewater treatment system, or soils surrounding said parts, excepting such activities which are carried out in conjunction with or resulting from new construction.

4.03.266  Saturated Soil
Saturated soil shall mean soil that has reached its moisture holding or "field" capacity.

4.03.268  Setback
Setback shall mean the horizontal distance as measured between the nearest points or edges of specified structures, features, wastewater treatment system components, and/or property lines. If the horizontal distance between a wastewater system component and a structure exceeds another distance between the component and the structure as measured in a straight line, "minimum setback" shall mean a straight-line distance.

4.03.270  Soil Depth
Soil depth shall mean the combined thickness of soil layers which are suitable for effluent soil absorption systems. Soil depth is measured vertically from the surface to bedrock, hardpan, or an impermeable soil layer.

4.03.271  Special Flood Hazard Area
Special Flood Hazard Area includes Zones A, AE, AH, AO, AR, A99, V, and VE as shown in the most current FEMA Flood maps for the Stinson Beach area.

4.03.273  Standard System
Standard system shall mean a wastewater treatment system that includes as its components for purposes of treatment:

1. a septic tank; and
2. a leach field (dispersal field)

A standard septic system may have other non-treatment components such as a distribution pump, tight line, etc.

4.03.276  Temporary Use
Temporary use shall mean a use, which either is active during three or fewer calendar months within any calendar year or is active for less than six consecutive months.

4.03.278  Treatment Component
Treatment component shall mean the elements or parts of a wastewater treatment system which are intended or designed to reduce the contaminants in wastewater prior to its combining with groundwater.

4.03.280  Unstable Landform
Unstable landform shall mean an area that shows evidence of mass downslope movement.

4.03.283  Wastewater
Any and all waste, substance, liquid or solid, which contains or may be contaminated by human waste or other substances that may be injurious or dangerous to health either directly or indirectly.

4.03.284  Wastewater Treatment System
Wastewater treatment system, dispersal system, or wastewater system shall mean any devices, parts, elements, structures, and/or components, located between the building and the point of discharge into soil.

4.03.285  Watercourse
Watercourse shall mean a definite open channel with bed and banks within which natural water flows either perennially, ephemerally, or intermittently including overflow channels contiguous to the main channel. A watercourse shall include both natural and manmade channels.

4.03.286  Water Bodies
Water bodies shall mean all of the Bolinas Lagoon, the Seadrift Lagoon, and the Pacific Ocean. Water bodies shall also include wetlands, seasonal wetlands as defined by the U.S. Army Corps of Engineers, or other bodies of water such as ponds or lakes.

4.03.288  Water System
Water system shall mean any water source, water treatment unit, water storage, or water distribution system, or any combination thereof, other than any such water system owned by the District or other public agency.

4.03.292  Well
Well shall mean any excavation that is drilled, cored, bored, washed, driven, dug, jetted, or otherwise constructed which excavation is intended to discover, locate, extract, or artificially recharge groundwater.