To: Zoning Administrator
From: Planning and Building Department
Agenda Section: Consent
SUBJECT:
title
Humboldt Bay Municipal Water District Tank Retrofit Project Coastal Development Permit
Assessor Parcel Number: 401-111-005
Record Number: PLN-2024-18913
Samoa area
A Coastal Development Permit for Humboldt Bay Municipal Water District to retrofit an existing one-million-gallon industrial water storage tank to increase resiliency to seismic events. Improvements will include a new roof and center column; installation of additional anchorage, three new flexible subsurface connections, tank appurtenances, and painting of the entire tank. The project will require the tank be drained to an on-site drainage dissipator, where untreated surface water will percolate into the sand.
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RECOMMENDATION(S):
Recommendation
That the Zoning Administrator:
1. Adopt the resolution (Resolution 24-__) (Attachment 1), which does the following:
a. Finds the project exempt from further environmental review pursuant to Section 15301 Existing Facilities and Section 15304 Minor Alterations of Land of the State CEQA Guidelines, and that there is no substantial evidence that the project will have a significant effect on the environment; and
b. Makes all required findings for approval of the Coastal Development Permit; and
c. Approves the Coastal Development Permit as recommended by staff and subject to the conditions of approval (Attachment 1A).
Body
DISCUSSION:
Project Location:
The project site is in the Samoa area, on the east side of New Navy Base Road, approximately 0.5 miles north of the intersection of New Navy Base Road and Bay Street.
Present Plan Land Use Designations:
Industrial General (MG), Humboldt Bay Area Plan (HBAP), Density = N/A. Slope Stability: Moderate Instability (2).
Present Zoning:
Industrial General (MG).
Environmental Review:
Project is exempt from environmental review per Section 15301 Existing Facilities and Section 15304 Minor Alterations to Land of the CEQA Guidelines.
State Appeal Status:
Project is located within the Appeal jurisdiction of the Coastal Zone and, therefore, is appealable to the California Coastal Commission.
Major Issues:
None.
Executive Summary: A Coastal Development Permit (CDP) for the Humboldt Bay Municipal Water District (HBMWD) to retrofit an existing one-million-gallon industrial water storage tank to increase resiliency to seismic events. The retrofit will include the following improvements:
• A new roof and center column to resist seismic-related sloshing waves within the tank;
• Installation of additional anchorage to the lower shell ring via a new 3-foot-wide concrete ring foundation and 59 helical soil anchors that will integrate with the existing foundation;
• Installation of three (3) new flexible subsurface piping connections to accommodate potential differential settlement from seismic events at necessary points of connection (which will require excavation, backfilling, and pavement patching);
• Tank appurtenances (such as a ladder); and
• Painting of the entire tank.
Before the work is completed, the tank will be drained to a drainage dissipator vault on-site and drained water will percolate into the sand. Draining the tank is covered under the Statewide General National Pollutant Discharge Elimination System (NPDES) Permit, under which HBMWD has coverage. The water in the tank is untreated surface water, so no dechlorination is required. Work would occur within previously disturbed areas. Staging would occur on the end of the existing access road and to the north, within a grassy area within the eastern portion of the parcel (see Plot Plan, Attachment 1B). As described on the Project Plans (Attachment 1C), erosion control measures would be implemented during project construction in compliance with a Stormwater Pollution Prevention Plan (SWPPP), to be prepared and implemented under the current NPDES Permit requirements, which has been incorporated as a condition of approval (Condition of Approval #4). Additionally, based on comments received from the Department of Public Works, Land Use Division in February 2024, the Department has requested several measures be implemented during project construction to reduce potential impacts to County roadways and drainage courses, including periodically cleaning roadways and implementing best management practices (BMPs) to prevent the tracking of material onto County roadways, not placing construction materials or debris within the County right of way, reducing the transport of sediment to drainage courses, and correcting any drainage problems causes as a result of the project, which have been incorporated as conditions of approval (Condition of Approval #5).
The County of Humboldt Web GIS portal indicates the site does not contain mapped wetlands or Streamside Management Areas (SMA), nor is the site within a mapped scenic area. Review of the California Department of Fish and Wildlife’s (CDFW) California Natural Diversity Database (CNDDB) portal in March 2024 indicates the site is within potential habitat for yellow rail (Coturnicops noveboracensis), a marsh bird that typically nests in shallow sedge marshes and winters in wet meadows and marshes with cordgrass, saltgrass, sedges, and other low vegetation. It is not anticipated that impacts to this species would occur, as the site does not contain suitable or marsh habitat. In addition, no tree removal would occur under the project. The project was referred to CDFW for review and comment; however, no response was received.
A Geotechnical Investigation Report (Attachment 1D) was prepared in July 2021 by Crawford and Associates, Inc., which assessed the geotechnical conditions of the subject site. As noted in the Report, the tank is a welded steel tank that was constructed in 1967 and is underlain by loose to very dense poorly graded sand and medium dense clayey sand to the maximum depth explored (51.5 feet). A liquefaction analysis was also performed and indicates there is a high potential for liquefaction, with liquefaction-induced settlement at the ground surface to be approximately 2 to 6 inches. To ensure geologic-related impacts are minimized to the greatest extent possible, the proposed improvements shall follow the foundation recommendations and seismic design parameters presented in the Report, which has been included as a condition of approval (Condition of Approval #6).
A Limited Hazardous Materials Survey Report, prepared by GHD in July 2021 (Attachment 1E), indicates two (2) samples collected from the subject site (roof at east handrail and exterior west wall at patch) contained lead containing paint. None of the materials sampled for the survey were reported by the analyzing laboratory to contain asbestos. However, although not sampled, a gasket at the pipe intersection with the tank is presumed to contain 2% chrysotile (serpentine form of asbestos). As such, all appropriate USEPA and Cal/OSHA regulations applicable to asbestos and lead containing materials apply. Per the Report, GHD recommends that asbestos materials be appropriately removed by a licensed abatement contractor prior to the commencement of work at the project site that may impact the hazardous materials described. While removal of all lead surface coatings is not required prior to work, impaction of material containing lead shall be conducted by appropriately licensed and trained personnel. Additionally, it is recommended that the Report be provided to contractors and/or personnel who conduct work at the project site and that the HBMWD maintain copies of this report for as long as the known hazardous materials remain at the project site, plus an additional period of 30 years. These recommendations have been incorporated as conditions of approval (Conditions of Approval #7).
The proposed water storage tank improvements are consistent with the Humboldt Bay Area Plan policies and would not occur in any sensitive habitat area or affect coastal resources. The subject property is not located within a designated Coastal Scenic Area in the Humboldt Bay Area Plan and the project is consistent with the Coastal Scenic policies of the Plan. In addition, the subject site is not identified as a location for Coastal Access. Specifically, the project is located east of New Navy Base Road and to the west of the road are the scenic views and public access area. Additionally, the project entails improvements to the existing water storage tank and would not introduce new development to the site. As such, the proposed improvements would not be anticipated to impact the scenic and visual qualities of the area, impact any views to or along the coast, or impact public access to coastal resources.
The project was referred to the Northwest Information Center (NWIC), Bear River Band of the Rohnerville Rancheria, Blue Lake Rancheria, and the Wiyot Tribe on February 14, 2024. Per comments received from NWIC on February 28, 2024, while the general vicinity has sensitivity for archaeological resources, the project area has low possibility of containing unrecorded archaeological site(s) and no further study is recommended, although NWIC recommends consulting with the local tribes. The Blue Lake Rancheria responded on February 20, 2024, that they had no knowledge of cultural resources in the project area and requested all ground disturbing activities be conditioned with the standard inadvertent discovery protocol. Bear River Band of the Rohnerville Rancheria recommended approval of the project on March 9, 2024, and did not provide any specific comments. Conditions of approval include the Inadvertent Discovery Protocol (Informational Note #1) should any resources be discovered during construction of the project.
OTHER AGENCY INVOLVEMENT:
The project was referred to responsible agencies and all responding agencies have either responded with no comment or recommended approval or conditional approval. (Attachment 3)
RECOMMENDATIONS:
Based on a review of Planning Division reference sources and comments from all involved referral agencies, Planning staff concludes that the applicant has submitted evidence in support of making all of the required findings for approval of the Coastal Development Permit. Staff recommends that the Zoning Administrator find the project exempt from further environmental review pursuant to Section 15301 Existing Facilities and Section 15304 Minor Alterations to Land of the State CEQA Guidelines, as there is no substantial evidence that the project will have a significant effect on the environment.
ALTERNATIVES TO STAFF RECOMMENDATIONS:
The Zoning Administrator could elect to add or delete conditions of approval. The Zoning Administrator could elect not to approve the project, or to require the applicant to submit further evidence, or modify the project. Modifications may cause potentially significant impacts, and additional CEQA analysis and findings may be required. These alternatives could be implemented if the Zoning Administrator is unable to make all of the required findings. Planning Division staff has stated that the required findings in support of the proposal have been made. Consequently, Planning staff does not recommend further consideration of either alternative.
ATTACHMENTS:
1. Draft Resolution
A. Conditions of Approval
B. Plot Plan
C. Project Plans
D. Geotechnical Investigation Report
E. Limited Hazardous Materials Survey Report
2. Applicant’s Evidence in Support of the Findings
3. Referral Agency Comments and Recommendations
Applicant
Humboldt Bay Municipal Water District
c/o John Friedenbach
P.O. Box 95
Eureka, CA 95502
Owner
Same as Applicant
Agent
GHD
Kerry McNamee
P.O. Box 1010
Eureka, CA 95502
Please contact Rodney Yandell, Senior Planner, at 707-268-3732 or by email at
ryandell@co.humboldt.ca.us if you have any questions about the scheduled item.