The owners of a Calistoga landfill have agreed to restore damaged property and pledge $2.6 million toward environmental projects as part of a settlement with Napa County that resolves violations the landfill incurred in 2019 following a 40,000-gallon toxic water spill, prosecutors announced Friday.
Clover Flat Landfill Inc. and Vista Corporation’s commitments pertain to a leachate spill at Clover Flat, off Silverado Trail. The California Department of Fish and Wildlife investigated the matter six years ago and also uncovered unauthorized removal of trees and vegetation, and road development through a stream, officials said.
The landfill was owned by the local Pestoni family in 2019 and it was acquired in February 2023 by Texas-based Waste Connections, parent company of Clover Flat and Vista Corp.
In a statement Friday, Waste Connections officials said they were “fully aware” they would need to resolve the matter and have been working diligently since taking over.
“(We’re) pleased that we were able to reach a positive resolution that both addresses these historical issues and ensures the continued long-term protection of the local environment through the support of restoration projects onsite and offsite from the facility,” the statement said.
Terms require the defendants to restore 4.24 acres of habitat in and around the landfill; remove the unauthorized road; and restore natural streams and vegetation. Restoration is expected to cost about $4 million with the additional $2.6 million going toward funding for other Napa County environmental restoration projects, according to the county District Attorney’s Office.
Funding and projects include:
$1.5 million for the Bale Slough-Bear Creek Tributary restoration project;
$954,000 for the Huichica Creek restoration project;
$150,000 for either the Huichica Creek or Suscol Creek restoration projects.
“This settlement reflects the severity of the leachate spill, as well as Clover Flat’s willingness to engage in a comprehensive and long-term environmental restoration plan,” District Attorney Allison Hayley said in a statement.
Her office added this week’s resolution only applies to the 2019 investigation and is unrelated to other matters involving the landfill.
In recent years, area residents and environmental groups have repeatedly expressed concerns about water contamination, recurring fires and hazardous working conditions.
Critics included former St. Helena Mayor Geoff Ellsworth, who in 2022 accused the landfill’s previous owners of negligence and reckless endangerment.
Citing economic challenges, Waste Connections has said it plans to close Clover Flat Landfill by 2027, .
Originally Published: September 12, 2025 at 5:12 PM PDT