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Woodacre and San Geronimo Flats Wastewater Group


September 2018 Newsletter
Executive Summary and Complete Draft Report
Executive Summary 2017
Spring 2017 Community Newsletter
New State Grant kicks off Supplemental Feasibility Study - September, 2016
2011 Questa Feasibility Study for Woodacre
Description of alternatives and costs - extract from 2011 Feasibility Study
Outreach area map
Community Interest in the Project
What is an EIR?
Woodacre Water Quality Report 2007
Report on Free and Anonymous Septic inspections 2007-08
Petition for Property Owners who support the EIR

Woodacre and San Geronimo Flats Wastewater Group

Frequently Asked Questions Regarding the Proposed Project
(Click on the below question to review the corresponding answer)

Why is this project being undertaken?
A number of properties in the San Geronimo Valley suffer from failing septic systems because of the poor soils, high groundwater, small parcels and age (most systems are 50 years old or more). In addition many homes are in close proximity to creeks. The Woodacre Flats with its high density of homes in particular suffers from failing systems. Ongoing water quality monitoring confirms that our streams have a high level of fecal coliform, and a free and anonymous inspection program in 2007 confirmed that many Woodacre homes have problems with their systems.
What is the goal of the project?
The community based effort seeks to repair or replace failed septic systems for existing homes on the "flats" or lowlands of Woodacre and possibly San Geronimo through either individual onsite wastewater (septic) systems, or through a community system.
What is the proposed Woodacre & San Geronimo Wastewater Project?
No specific project has been identified, as we are still in an information gathering phase. A feasibility study in 2011 was funded by donations from the community, the US Environmental Protection Agency (EPA) and the County. Conducted by Questa Engineering, the study identified and analyzed four possible alternatives:

1. No project (i.e., leave the substandard systems in place)
2. Fix septic systems onsite (e.g., with mound systems or alternative systems)
3. Build a “STEP” system for up to 150 homes in Woodacre.  A STEP system keeps solid waste in a septic tank on each parcel, then transports liquid effluent to a shared leach field, proposed to be located on the south ridge of Woodacre.
4. Build a recycled wastewater system, to serve up to 200 homes in Woodacre and possibly San Geronimo. In this alternative, all sewage would be collected (eliminating tanks) and taken to a small treatment plant located in the maintenance buildings on the SGV Golf Course. The highly treated water would be stored in a pond then mingled with the irrigation water on the Golf Course.  

According to Questa Engineering, an additional opportunity exists to expand alternative 4, with an additional pond on "the back nine" serving up to an additional 100 homes or more, with a maximum of 300. This was not studied in the Feasibility Study and needs to be reviewed. The limiting constraint on the size of the system and number of homes is the size of the ponds holding treated water. The Golf Course has limited space for ponds; therefore the number of homes that can join the system is limited.

The project is currently being studied, and no alternative has yet been chosen.

Who is leading this effort and what process have they undertaken?
The Woodacre Flats Wastewater Group consists of a dozen community leaders who have been meeting since 2007 with the goal of addressing failing systems and protecting the environment. While the group originally consisted of Woodacre property owners, several San Geronimo residents have now joined the group to advocate for inclusion of portions of San Geronimo. The group has conducted extensive research and fundraising, and has held more than 20 meetings in Woodacre and San Geronimo. The group has met several times with the SGV Planning Group, the Stewards, and SPAWN, as well as maintaining a biannual newsletter to property owners. Multiple mailings and announcements have provided information. The group has also been fundraising in the community for the 2011 Feasibility Study, and now the Environmental Impact Report (see below).

What is the current status of the project?

More feasibility work is needed on the potential expansion of alternative 4) to include San Geronimo. The County has received a $75,000 grant from the Regional Water Quality Control Board to expand the 2011 Woodacre Flats Wastewater Feasibility study to include the San Geronimo Flats. The Supplemental Feasibility Study will begin in late September of 2016, following a community meeting on September 22.

Soon after the supplemental feasibility study the Environmental Impact Report (EIR) will begin and the two studies will be conducted concurrently. A scoping meeting for the EIR will be held in late Fall of 2016. The EIR is an essential step to consider the alternatives and their potential impacts, and must be taken before there is a decision about which alternative will be selected as the planned project.

The total projected cost for the expanded feasibility study and environmental review is $290,000. The County has approved $105,000 in matching funds to prepare the EIR. Additional funding sources for the environmental review include $38,000 in donations from the Woodacre/San Geronimo community and a $50,000 grant from the Marin Municipal Water District. The County's Environmental Health Services Department (EHS) will provide a $22,000 in-kind match of staff time towards managing the overall project.

Which properties could be affected by the project?
Hooking up to the proposed system will be entirely voluntary. Property owners on the Woodacre Flats and San Geronimo Flats will have the option to hook up. These areas have been the focus of this project because of the known high rate of failing septic systems, due to soils, high groundwater, small parcels and age (most are 50 years old or greater). These areas are also in the closest proximity to streams.
Who decides on the project?
The Board of Supervisors will ultimately decide on a preferred alternative. That decision will be based on several factors, including:

Input received in an extensive community based process
Consideration of potential environmental impacts as described in the EIR
Support from responsible public agencies
A successful vote by property owners hooking up to the system, endorsing an assessment to pay for the system
How much will the project cost?
See the attached summary sheet showing costs. (From the 2011 Feasibility Study)
Who pays for the project and maintenance/administration?
The project will be funded by the property owners who are connecting to the system, and, it is hoped, by State or Federal grants. The property owners' contribution can be financed over time, through an assessment district, which would be formed by the Board of Supervisors.
How will the project be managed in the short and long term?
The County will be responsible for constructing a community project (using contractors) and for the future management and maintenance of the system or individual onsite systems. This could be done through a legal entity such as a "Wastewater Disposal Zone" and assessment district. Costs for management and monitoring will be paid by the property owners who connect to the system(s), through an annual fee.

This fee will cover all ongoing regular maintenance of the system(s), and will be subject to cost of living increases, to ensure that all is maintained in good condition. The County will likely hire a contractor for all maintenance, monitoring, and reporting. The Golf Course will not manage Alternative 4; in this alternative the Golf Course staff would only handle the flow of treated water to the existing irrigation system on the Golf Course.

Will the project trigger more development in the Valley?

The project will only serve existing homes (the number served will depend on the alternative chosen, with a maximum of about 300), and will not trigger development of undeveloped parcels. Depending on the alternative chosen, there may be potential for people to expand their homes. Improving onsite systems with Advantex or other modern onsite systems would in many cases enable homeowners to expand their homes.

If a community system is selected, homeowners connecting to the proposed system will no longer be subject to septic regulations, and they may have greater potential to make additions to their homes, or to legalize unpermitted structures. The Marshall community built a similar wastewater system and addressed this by requiring that all homes connected to the system be limited to future additions of no more than 500 square feet. This limitation is enforced by the County through a deed restriction. Following three community meetings and a community survey on this topic, the Woodacre/San Geronimo Flats Group has recommended to the County that the EIR evaluate two alternatives:

1) a deed restriction which allows no additions, and
2) Deed restrictions which allow additions of up to 500 square feet, or any sized addition to bring the home to the median home size, whichever is greater.

In addition the W/SG Flats Group recommends allowing homes hooking up to the system to legalize any unpermitted building built before 2007, subject to all other county regulations. A decision about the potential expansion of homes will be made by the Board of Supervisors, with community input, after the feasibility study and EIR.

Are our creeks polluted or designated as “impaired”, and which regulations manage pollution?

There are both federal and state regulations which designate pollution standards and identify which water bodies are polluted. Under the Federal Clean Water Act 303(d) list, Lagunitas Creek is identified as impaired for pathogens, nutrients and sediment. Additionally, the Tomales Bay Watershed and its tributaries are listed as impaired for pathogens, nutrients, sediment and mercury. The 2005 regulatory process called the Tomales Bay Pathogen Total Maximum Daily Load (TMDL) specifically identified San Geronimo, Arroyo, Woodacre, and Montezuma Creeks as exceeding standards for pathogens, and identifies failing septic systems as a key source of fecal coliform.

An annual water quality monitoring program by the County confirms frequent exceedances of water contact standards for fecal coliform at a monitoring site above the Inkwells. The State of California has recently issued a new law calling for standardization of regulations managing septic systems, in a regulation called AB885 or the "Onsite Wastewater System Policy" places the highest restrictions on systems within 600 feet of an impaired water body.

Will the project trigger additional sewer systems in the Valley?
No. We learned from the Feasibility Study is that there are limited options for addressing wastewater in the Valley, and community wastewater systems or sewer systems are especially difficult. This is due to the relatively large area needed for such a system, and because of the physical features of the Valley – hills, poor soils, high groundwater, and existing development. There are few areas suitable for community leachfields or ponds. Building a large urban-style sewer system is financially infeasible and there is no location in the Valley for such a system. Likewise connecting to sewer districts in East Marin is financially infeasible and likely politically very difficult.

The biggest alternative being considered, the recycled water treatment plant, is limited by the same constraints to a maximum capacity of about 300 homes. This is because the sites where the proposed pond(s) are located are limited in size, and in turn the ponds are limited in size by space available. The limit on capacity is a good feature because it prevents hook up of new developments, and ensures the project will only serve existing homes.

Is the project compatible with San Geronimo Valley (SGV) Community Plan?
An important element of the proposed EIR process is to determine a project's consistency with the Countywide Plan and SGV Community Plan.

It is noted that the SGV Community Plan recognizes a history of periodic septic system failures in the Planning Area. The proposed project is consistent with the Plan's Policy ER-2.1 calling for the County to protect the creekside environment. By reducing contamination from failing septic systems, the project would be consistent with Policy 2.4, which calls for property owners to protect aquatic habitat, in particular for Coho salmon, steelhead trout, and California freshwater shrimp.

The Community Plan also calls for consistency with the Countywide Plan (ER 2.1), which has provisions for development within stream conservation areas (SCA.) Since many of the existing septic tanks and leach fields are currently located within the 100-foot SCA, the proposed project would encourage consistency.

It is important to recognize that new development within the San Geronimo Valley would remain subject to County zoning regulation and codes, as well as the need to be consistent with the Countywide and Community Plans.
If the Recycled Water Treatment Plant is chosen, where would the treatment plant be located?

The treatment facility for the water recycling alternative would be located at the golf course maintenance area, not in downtown Woodacre. The preferred treatment alternative would entail the use of a microfiltration membrane bioreactor (MBR) system that would be fully enclosed within an approximately 2,000-square foot building which will be located amongst the existing buildings on the Golf Course.

Because the MBR system would be contained within a building, it will include facilities for collection, scrubbing and venting of sewage gases to prevent escape of odors beyond the building treatment plant area. It is estimated that sludge would be hauled away for disposal about once a month to a qualified septage receiving facility. The clean water from the MBR unit would be stored in ponds on the golf course without creating an odor problem and would be used for irrigation. Some water in the pond could recharge the ground water.

The ponds would go dry in the fall, prior to the onset of the winter rainy season. One point of confusion is the size of the building enclosing the treatment plant. The 2011 Feasibility Study suggests a facility could be 10,000 square feet. 8,000 of that would be for parking and a driveway and other site improvements. But since parking and a driveway already exist at the golf course, the only new facility would be the 2,000 square foot building housing the MBR unit.

If an assessment district is formed, will properties that join "displace" properties that are failing?
When an assessment district is formed, all properties within the boundaries may join (or not). The goal of the project is to include parcels in the area of highest risk of failure and in proximity to streams. Failing systems that are not part of the project area would still need to find solutions to their septic problems. In these cases, other alternative systems may be more appropriate, and the County is available to work with community members to consider individual or group solutions. The Woodacre/San Geronimo Flats Group will be happy to help too.
Will new technologies for on-site development be considered as part of the expanded feasibility study?
Yes. The 2011 Woodacre Flats Feasibility Study, did include new technologies for onsite systems such as the Advantex system. The anticipated expanded feasibility study will examine other alternative wastewater technologies suitable for onsite system upgrades to overcome local soil, groundwater, and drainage constraints. This will include any new technologies that may have become available since 2011. This is consistent with SGV Community Plan policy CD-4.1.
Why does the project serve some homes and not others?

The project originated with the Tomales Bay Watershed Council which identified Woodacre as having the worst problems with septic systems, and facilitated the creation of the Woodacre/San Geronimo Wastewater Group.

Subsequent discussions with the County and Questa Engineering confirmed that the density of homes in Woodacre, combined with high groundwater, small parcel size, age of systems and proximity to streams made the Woodacre Flats the worst area for operation of conventional septic systems. Alternative 2, repair of onsite systems, is not constrained to Woodacre and San Geronimo but would need to be phased. But the community systems are constrained by physical conditions. In the case of alternative 3, the size of the leach field, and alternative 4, the size of the ponds to hold treated water.

Each individual property owner, or group of property owners must look at the available land to assess opportunities and constraints, as was done in Woodacre. For many, onsite systems may be the best option. We encourage other areas within the Villages to work together, and we will be happy to be of assistance.

Will the project benefit other property owners in the Valley?
While the number of properties hooking up to this project is limited, the project will benefit the entire Valley by improving water quality. By forming a management district, the project provides a management structure for future individual or groups of homeowners who need help with repairing their own septic systems. This could include other small community systems to serve groups of homes. In addition a management district can assist new properties joining the district with financing and management.
Will the project smell?
Odors vary with each alternative and will be evaluated in detail in the EIR. We are working to identify examples of similar systems so that we can visit them to assess odors ourselves. It is important to remember that onsite systems, whatever their location, need regular pumping and that produces odors. Alternative 2, the repair and replacement of onsite systems would cause odors when systems are pumped or maintained. Alternative 3, the "STEP" system, preserves tanks onsite and pumps effluent to a leachfield. Again, pumping of tanks causes odors, and maintenance of pump stations would cause odors. Alternative 4 would likely have the least odors, as the system does not require septic tanks on each property. Monthly pumping of solid wastes at the golf course would produce odors, and occasional maintenance of pumps in Woodacre or San Geronimo would cause odors.

How will the project work with the Golf Course? What if the Golf Course goes away?
The owners of the San Geronimo Golf Course are very supportive of Alternative 4, the recycled wastewater project because it will supply irrigation water, and they have offered land for ponds to store the treated water.

If this alternative is chosen, the County would create a long term contract with the Golf Course, following a negotiation, to ensure a fair compensation to the Golf Course while also protecting public benefit. The contract would include guarantees for the future of the system in any scenario, including closure of the Golf Course. It is important to remember that the treated water remains a valuable resource even if the Golf Course goes away. The Golf Course owners have expressed an interest in joining the system and if the project goes forward would be provided with a limited hook up to serve their existing use.

Will the project use and store chemicals?
The first three alternatives do not require chemicals, and in Alternative 4, the use of disinfectants is an option. Alternative 4 involves a biomembrane filter process, followed by disinfection. Disinfection can be done through either a UV process or use of chemicals (not chlorine). This disinfection process will likely be determined by the permitting agency, the Regional Water Quality Control Board (RWQCB). If chemicals are used volumes will be very limited and will be managed professionally, with inspections by the County and RWQCB confirming safety.
How will mosquitos be prevented?
The project will be subject to the requirements of the Marin/Sonoma Mosquito and Vector Control District. The District has a West Marin Committee, which ensures that the District uses only organic methods for controlling mosquitos in West Marin, so that organic farms do not lose their organic certification and so that aquatic species are not harmed.
Will the project be at risk of catastrophic failure as has happened in East Marin? Who will be responsible and pay fines?

It has been suggested that the community system alternatives 3 and 4 pose a risk of catastrophic failure "like Ross Valley." It is important to remember that the Ross Valley system serves 50,000 people and has over 200 miles of pipeline, in a system that in parts is over a century old. There simply is no comparison.

Any alternative that is chosen, whether onsite systems or a community system, would be built to modern standards in conformance with a permit from the Regional Water Quality Control Board, and subject to rigorous maintenance and monitoring, overseen by the County. The project will be financed appropriately and built well. The County would bear the responsibility and liability for the system (as with the Marshall and San Quentin systems), but all costs are paid by the property owners hooking up to the system.

For more information, contact:
Lorene Jackson
Project Manager, Marin County Environmental Health Services Division, 473-7146

Christin Anderson
Woodacre Flats representative, 488-4702

Ann Seramin
San Geronimo representative, at 488-4775

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