Local Agency Management Program for Onsite Wastewater Treatment Systems (Septic Systems)

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1 Local Agency Management Program for Onsite Wastewater Treatment Systems (Septic Systems) South County Environmental Compliance Workshop April 25, 2018 Monterey County Health Department, Environmental Health Bureau

2 What is an Onsite Wastewater Treatment System?

3 Septic Tank Holds wastewater long enough to allow the solids to settle out or float (forming sludge or scum) and the liquid portion moves out to the dispersal field.

4 Dispersal Systems The wastewater exits the septic tank and is discharged into the dispersal field for further treatment by the soil. Leach Fields Seepage Pit Overhead Cross Section

5 Soil Matters ALOT The soil is the most important part of the septic system and must be evaluated and protected properly. If there is inadequate soil between the bottom of the dispersal field and groundwater, the wastewater will not be treated before it enters the groundwater. If the soil is too dense, it will not absorb all the wastewater, forcing it to the surface.

6 Conventional vs. Alternative OWTS CONVENTIONAL ALTERNATIVE (SUPPLEMENTAL) Effluent Quality Construction Costs O & M Costs Effluent Quality Construction Costs O & M Costs

7 Types of OWTS CONVENTIONAL Septic tank with rock-filled leachfield Passive system, flows by gravity Wastewater treatment occurs in the soil ALTERNATIVE (SUPPLEMENTAL) Aerobic treatment unit or Media filter/packed filter bed with a dispersal system Active system, requires electricity, telemetry, and ongoing maintenance Wastewater treatment occurs before distribution of effluent in the soil

8 OWTS Regulatory Structure State Water Resources Control Board Central Coast Regional Water Quality Control Board Monterey County Health Department, Environmental Health Bureau

9 What is the OWTS Policy? A statewide, risk-based, tiered approach for the regulation and management of OWTS installations and replacements. It sets the level of performance and protection expected from new OWTS and repairs/expansions to existing OWTS.

10 Why do we need a LAMP? Opportunity for Monterey County to propose modified standards that meet or exceed the requirements of Tier 1 and are protective of water quality and public health protection objectives. Consider local geology Consider local practices Allow for alternative (supplemental) systems

11 LAMP Overview Existing OWTS Existing, functioning OWTS No changes required as long as the system continue to function properly EXCEPTION: CESSPOOLS MUST BE PROPERLY DESTROYED AND REPLACED UPON DISCOVERY Liquid waste haulers will be required to report all septic tank pump outs in Monterey County

12 LAMP Overview Existing OWTS Failed / Surfacing OWTS Existing OWTS that are surfacing or backing up into the home plumbing are considered to be in failure and must be repaired or replaced. OWTS discovered to contaminate groundwater, surface water or public health shall also be repaired or replaced. Any OWTS permits issued or modified after the LAMP is adopted will be subject to its requirements and restrictions.

13 LAMP Overview Site Evaluation **STANDARDS PROPOSED in MONTEREY COUNTY LAMP** Site evaluation work must be completed by a qualified professional REPAIRS TO EXISTING OWTS Deep groundwater monitoring boring Soil profile analysis (boring or excavation) to at least 3 past depth of proposed dispersal system NEW OWTS Deep groundwater monitoring boring, including soil profile description Soil profile analysis (boring or excavation) to at least 3 past depth of proposed dispersal system and Percolation testing in both initial and backup dispersal field areas

14 LAMP Overview Design Criteria **STANDARDS PROPOSED in MONTEREY COUNTY LAMP** ALL OWTS 10 maximum dispersal field depth without supplemental treatment No impermeable surfaces over dispersal field without supplemental treatment Variable application rate (square footage) based on percolation rate of soil OWTS must be designed by a qualified designer

15 Next Steps May 10, Final LAMP at Central Coast RWQCB (San Luis Obispo) for Adoption May 11, 2018 Approved Final LAMP Effective Date May 13, 2018 Tier 1 Standards become effective if LAMP not approved

16 Thank You! LAMP comments may be directed to Nicki Fowler at the Environmental Health Bureau or (831)