To: Honorable Mayor and Members of City Council
From: Joy Eldredge, Utilities Director
Prepared By: Chris Jones, Senior Civil Engineer
TITLE:
Title
Hidden Glen Remediation Project
LABEL
RECOMMENDED ACTION:
Recommendation
Adopt a resolution: (1) authorizing the Utilities Director to approve change orders and charges for project services up to $462,684 for a total contract amount not to exceed $1,020,580; and (2) amending the Project budget as documented in Council Budget Amendment No.71P4; and (3) determining that the actions authorized by this resolution were adequately analyzed by a previous CEQA action.
Body
DISCUSSION:
The City of Napa is required to complete the Hidden Glen Remediation Project on City-owned property (the “Project”) to comply with County of Napa Environmental Health, Solid Waste Local Enforcement Agency (LEA) requirements. The City-owned property is 2.18 acres which includes the former Hidden Glen Dump (approximately 1.06 acres) listed in the CalRecycle Solid Waste Information System (SWIS) database and assigned SWIS NO. 28-AA-0028 (the “Project Site”). The Project Site (APN #045-411-022-000) is near the intersection of Pascale Place and Glory Court near Coombsville Road in East Napa. See Attachment 2 for Site Plan.
The Project Site was initially an excavated quarry that operated into the 1940’s. After quarry operations were abandoned, the Project Site was used as a general garbage dump by a private operator until it was abandoned in the 1960’s. In 2001, a landfill cap was installed at the dump site. In 2020, three (3) methane monitoring wells were installed by the City to monitor landfill gases based on directive from the LEA. Methane monitoring results have been below regulatory limits during all monitoring events. These wells would remain in place under the Project.
The Project Site is a vacant City-owned property and consists of a capped portion of the Hidden Glen Dump and the area between the capped area and the adjacent properties that extends beyond the area that was capped, referred to as the “buffer zone” (see Attachment 2). Waste-impacted soils were identified in the buffer zone and flag section that contain elevated lead concentrations and require remediation.
On November 26, 2019, the LEA issued a letter to the City of Napa requiring submittal of a workplan to ensure that State Minimum Standards are addressed at the City-owned parcel and in compliance with Title 27 of the CCR. To comply with State Minimum Standards, the letter requires the City to remove and/or cover waste-impacted soil along the flag section and the buffer zone.
A Remedial Action Plan (RAP) was prepared by Ninyo & Moore in October 2024 and approved by the LEA on December 20, 2024. Under the RAP, waste-impacted soil around the perimeter of the landfill cap is required to be excavated to bedrock or covered with 2 feet of clean imported soil. The waste-impacted soil is then required to be hauled offsite to an appropriate landfill for disposal or reconsolidated onsite and covered with a minimum of two feet of clean fill essentially capping it in place.
The City prepared construction plans for the Project which require all waste impacted soil to be reconsolidated onsite and covered with a minimum of two feet of clean fill. The construction plans include grading and covering of waste-impacted soil from adjacent properties subject to executed agreements in place between the City and the property owners.
On June 16, 2026, City Council authorized the Utilities Director to execute a construction contract with Innovative Construction Solutions in the amount of $557,896 and to approve change orders and charges for project services up to $282,684 for a total construction budget of $840,580. The $282,684 budget included $199,000 for project services including environmental monitoring, inspection, and geotechnical and engineering services and $83,684 for construction contingency. As described below, an additional construction contingency budget of $180,000 is required to complete the work.
The original construction contingency budget of $83,684 has been used for extra work on the project including tree removal and disposal, bedrock excavation, construction of additional drainage swales, additional waste-soil excavation, paving repairs on Pascal Place, and additional erosion control efforts to winterize the slopes on the site. The additional $180,000 for construction services is necessary for additional import, placing, and grading of clean fill to cover waste-impacted soil and tree planting, irrigation, and fencing as described below.
$150,000 is estimated to import, place and grade an additional 2,300 cubic yards of clean fill soil on the site. Additional clean fill is necessary to cover a larger than expected area of the property with 2 feet of fill, based on site conditions, rather than 1 foot of fill per the plans, to be fully compliant with the LEA approved RAP.
$30,000 is estimated to plant ten Live Oak trees, install a temporary irrigation system, and install fencing along a grove of trees where existing soil was unable to be removed. Due to additional soil and bedrock excavation along the Pascale Place frontage, three large Live Oak trees had to be removed. With coordination from the Parks and Recreation Department, it was determined that ten Live Oak trees should be planted in the area where the large trees were removed and a temporary irrigation system with a battery-operated controller should be installed. The fencing is required by the LEA to restrict public access to a small grove of trees on the south-east corner of the property near Lots 5 and 6 where waste soil was partially excavated and covered with clean fill while preserving the root systems of approximately fifteen trees.
The City received a grant for the Project from the Department of Resources Recycling and Recovery (CalRecycle) Legacy Disposal Site Abatement Partial Grant Program for reimbursement up to a maximum amount of $473,415. Among other eligible work tasks, grant funds can be used to cover the additional costs for importing, placing and grading clean fill.
FINANCIAL IMPACTS:
The current construction budget for the Project is $840,580. Council Budget Amendment No. 71P4 adds a $180,000 transfer from Risk Fund reserves for a total Project budget not to exceed $1,020,580. There are sufficient funds in the City’s Risk Fund Reserves to cover the Project.
Grant funds up to a maximum of $473,415 are available for specific activities associated with the Project. To date, $90,664 of the grant funds have been used based on agreements with adjacent property owners, which leaves $382,751 available to offset Project costs.
CEQA:
City staff recommends that the City Council determine that the potential environmental effects of the Recommended Action described in this Agenda Report were adequately analyzed by the Final Initial Study/Mitigated Negative Declaration prepared for the Hidden Glen Remediation Project, adopted September 2, 2025, (Resolution No. R2025-101), pursuant to the California Environmental Quality Act Guidelines, Code of California Regulations, Title XIV, Section 15000 et seq. (“CEQA”). Additionally, since that adoption, there have been no changes proposed in the project, no changes with respect to the circumstances under which the project is undertaken, and no new information which will require revisions to the IS/MND consistent with CEQA Guidelines 15162 and 15164.
DOCUMENTS ATTACHED:
ATCH 1 - Resolution
EX A - Council Budget Amendment No. 71P4
ATCH 2 - Site Plan
NOTIFICATION:
None