Title
Consider receiving a report on the DWR Bulletin 74: California Well Standards Update Project and providing input to Staff for upcoming Technical Advisory Committee meetings.
Report
RECOMMENDATION:
It is recommended that the Basin Management Advisory Committee:
Receive a report on the DWR Bulletin 74: California Well Standards Update Project and provide input to Staff for upcoming Technical Advisory Committee meetings.
SUMMARY:
The California Department of Water Resources (DWR) is in the process of updating the State Well Standards, known as Bulletin 74, which was last updated in 1991. Upon completion of the update, Bulletin 74 will be submitted to the State Water Resources Control Board for adoption into a Statewide Model Well Ordinance (<https://water.ca.gov/well-standards>).
DWR has formed a Technical Advisory Committee (TAC) as part of the updating process and, as the MCWRA Board of Directors was informed in January 2021, Staff Hydrologist Amy Woodrow (“Staff”) has been selected by DWR to participate on the TAC.
DISCUSSION:
TAC Process
The TAC process is designed to occur in two phases; each phase involves meetings of several small focus groups of TAC members during which the focus group discusses a specific aspect of the Well Standards. The first phase occurs from March - June 2021 and the second from November 2021 - February 2022. The full TAC will reconvene in August 2022 to preview the Public Review Draft and again in December 2022 to preview the Final Standards before DWR submits them to the State Water Resources Control Board for adoption into the Model Well Ordinance.
As a TAC participant, Staff will serve as a liaison to MCWRA’s stakeholders by soliciting input and reporting on outcomes from the DWR Bulletin 74: California Well Standards Update Project. Outreach by Staff will be provided through updates to the Basin Management Advisory Committee (“BMAC”) and the MCWRA Board of Directors.
Focus Groups
Focus group topics for the first phase include Water Well Siting and Design, Sealing Materials and Placement, Large Diameter Infiltration/Recharge Wells, Non-Vertical Wells, and Destruction. Focus group topics for the second phase include Water Wells, Monitoring Wells, Cathodic Protection Wells, and Geothermal Heat Exchange Wells.
Staff has been assigned to the Water Well Siting and Design focus group for the first phase and the Water Wells focus group for the second phase.
Meetings To-Date
The first TAC Plenary meeting was held on March 1, 2021 to kick off the DWR Bulletin 74 Update Project, review the TAC Charter, and address questions from TAC members. A summary of that meeting is provided as Attachment 1.
Meetings of three focus groups occurred in March 2021; Staff participated in the Water Well Siting and Design Focus Group (“Focus Group”) meeting on March 15, 2021 (Attachment 2). The Focus Group meeting covered the following topics: depth of annular surface seals, sealing-off strata, inter-aquifer seals, setbacks, and floodproofing a wellhead.
The Focus Group discussion was guided by a series of questions posed by DWR. Background reading was required of TAC members prior to the Focus Group meeting to support and provide context to the discussion questions, summarized below with additional detail in Attachment 3.
1. Depth of Annular Seal
a. Can we do better than “somewhat arbitrary” “customs and practices” for annular surface seal lengths?
b. What would an annular surface seal depth based on geology look like?
c. CCDEH/CGA comments recommend a single fixed minimum annular surface seal depth of 50 feet regardless of hydrogeologic conditions and intended well use. This recognizes that the mechanism for contamination is the same, no matter the intended use of the well. If one single depth is applied, what should the depth be?
d. What are the advantages and disadvantages of requiring that the annular surface seal be extended from the ground surface to the top of the uppermost screen interval (minus gravel reservoir + transition seal, as needed)?
2. Sealing-off Strata
a. How can it be assured that existing undesirable groundwater quality is being identified to support decisions about sealing off strata as required by the current Standards (i.e., what are the available tools and techniques and what is a reasonable level of effort)?
b. Are the efforts described in response to above Question reasonable and practical for all water wells (e.g. municipal, domestic, industrial, and agricultural)?
c. What should be the course of action in the absence of sufficient water quality information?
3. Inter-Aquifer Seals
a. For protecting aquifers from future contamination, is it a best practice to separate adjacent aquifers (of known or unknown water quality) with inter-aquifer seals?
b. What current well logging practices can be used to consistently identify aquifers as defined in Bulletin 74?
c. Can inter-aquifer seals be required for the protection of the aquifer in a way that is consistent and enforceable?
4. Setbacks
a. Are minimum separation distances an important aspect of the well system for protecting the aquifer from contamination via the well structure? How?
b. If important, can the empirically-based minimum separation distances in Bulletin 74 be improved?
c. As an alternative to the empirically-based setbacks in Bulletin 74, what would a standard for site-specific setbacks look like?
5. Floodproofing a Wellhead
a. Should all wells be protected from flooding at the same level as community water supply wells (e.g., 100-year)?
b. How do we deal with areas below mean sea level such as exist in the Sacramento-San Joaquin River Delta?
c. Should the Standards specify “alternate means of production?” What are they?
Opportunities for Participation
Staff will provide regular updates to BMAC and the MCWRA Board of Directors. Meeting summaries and discussion questions from the Focus Group will be shared. Responses to the Focus Group questions from Committee members, Directors, and the public will be brought back to the TAC.
Meetings of the Focus Groups and Plenary meetings of the TAC are available to the public via YouTube live stream, though there is not a mechanism for the public to provide real-time input during the meetings.
Members of the public can also participate in the update process by receiving email updates from DWR, submitting comments directly to DWR through an online comment portal or via email, and providing comments once the public review draft is released in September 2022. Details on these engagement opportunities is available at <https://water.ca.gov/well-standards>.
OTHER AGENCY INVOLVEMENT:
The DWR Bulletin 74: California Well Standards Update Project is being coordinated by the California Department of Water Resources. County staff from the Environmental Health Bureau are members of the California Conference of Directors of Environmental Health (CCDEH) which, in collaboration with the California Groundwater Association (CGA), are also active participants in the DWR Bulletin 74: California Well Standards Update Project.
FINANCING:
Fund 132
Prepared by: Amy Woodrow, Hydrologist, (831) 755-4860
Howard Franklin, Senior Hydrologist, (831) 755-4860