The NorthWest Petaluma California Rural Alliance's
Petaluma Mushroom Farm Info

"We are alarmed by the recurrent nature of the illicit discharges at the Petaluma Mushroom Farm and the facility's apparent disregard for the County and State permit requirements.
Illicit discharges and inadequate waste management practices have persisted at the facility"
- CA Regional Water Quality Control Board 7/27/00

"In my over ten years of advocacy on behalf of the Bay and its watershed, this is the first time I am aware of a local creek being literally cauterized by animal waste." - Michael Lozeau, San Francisco BayKeeper 11/1/99

  • January 29, 2022: 16 years after the Mushroom Farm quit, our neighborhood is again under assault from an environmental hazard. The Muir Wood Treatment Center has opened multiple operations in West Petaluma, and is looking to expand further. These facilities present a risk to the community from run-aways, have impacted noise, lighting, traffic, property values, water usage. They have gamed the system to enable their expansion efforts. See details at: skillmanneighbors.org

  • February 3, 2006: "Mushroom farm calls it quits" See Santa Rosa Press Democrat 2/3/06
  • January 24, 2005: Foul Odors, wastewater problems, follow the Petaluma Mushroom Farm to Colusa. Colusa County District Attorney filed lawsuit in Superior Court, People of the State of California v. Colusa Mushroom, Inc., and Colusa Industrial Properties, Inc. The suit alleges Wastewater and Odor Violations, Unlawful and/or Unfair Business Competition, and Public Nuisance. See Colusa Superior Court Case CV23333 1/24/05:
    • "The People of the State of California seek to prohibit Defendants from continuing to cause and allow nuisance odors from their facilities. Such odors constitute a public nuisance under both the Civil Code and in the common law of this state. Moreover, the People seek civil penalties and damages from Defendants for violations of the Business and Professions Code (pursuant to §§ 17200 -17209)."
    • "Because the design or capacity of the composting and wastewater system at the facility is inadequate, and given the Defendants' past history of wastewater and odor discharges, it is highly likely that Defendants will continue to discharge wastewater and odors in violation of law. The People are entitled to a preliminary and permanent injunction restraining Defendants from continuing to operate the facility in a manner likely to result in further violations."
    • "The operation of a composting facility without adequate wastewater treatment and/or odor containment inevitably results in the discharge of nuisance odors into the air and prohibits the enjoyment of our natural resources by the citizens of California, and constitutes a continuing nuisance to the surrounding environs pursuant to sections 3479 and 3480 of the California Civil Code. "
    • "The inadequate design and maintenance of Defendants' facility constitutes a condition which is harmful to the environment."
    • "Defendants herein be assessed a civil penalty of TWENTY-FIVE HUNDRED ($2,500.00) for each act of unfair competition, in an amount according to proof, pursuant to Business and Profession Code section 17206."
    • "Defendants be disgorged of any profits received from the unlawful, unfair or fraudulent act(s)."
  • Febuary 11, 2003: Mushoom composting operation has been removed. Sonoma County Code Enforcement has determined that the compost operation has been removed from the Petaluma Mushroom Farm's Thompson Lane location as of February 1, 2003. The farm has an additional 90 days to clean up the site. 
    • Condition 50 of the Farm's use permit states: "50. By  December 1, 2002, the composting facilities shall be removed from the subject parcel. Within 90 days of such removal, the applicant shall be responsible for removal of all compost materials and clean up of all toxic residue in the outdoor composting wharf area to prevent runoff from the site into Marin Creek and adjacent properties. A report shall be submitted within 30 days after the cleanup from the applicant's engineer describing the cleanup methods used and evidence that no further toxic residue exists on the site."
    • Envirronmental cleanup, installation of test wells, and monitoring, as required by California Regional Water Quality Control Board are still to be completed. See Cleanup and Abatement Order No. 00-105, subsequent Amendments, and Work Plan.
CA Regional Water Quality Control Board Compliance Status Report:
CA Regional Water Quality Control Board 7/27/00 - "We are alarmed by the recurrent nature of the illicit discharges at the Petaluma Mushroom Farm and the facility's apparent disregard for the County and State permit requirements. Illicit discharges and inadequate waste management practices have persisted at the facility despite Regional Board's issuance of a Notice to Comply (January 6, 1999) page 1, page 2 and a Notice of Violation (April 30,1999), the Superior Court's Judgement and Permanent Injunction (September 23, 1999), and the County's determination regarding septic system violations."
BayKeeper Action:
These photos of Marin Creek were taken by Baykeeper 11/6/98. They were used by District Attorney Jeff Holtzman in the prosecution of the Petaluma Mushroom Farm in Superior Court. Shown are Marin Creek (dry) upstream of the Farm, the discharge pipe from the Farm directly into the creek, and the creek downstream from the Farm, running with Diazinon contaminated Mushroom Farm waste.
click to enlarge:

Superior Court Action:
On September 23, 1999, the Mushroom Farm settled in Sonoma County Superior Court Case #222564 for of Pollution of a Waterway (Ca. Fish & Game Code #5650a6) and Unfair Business Competition (Ca. Business & Professional Code #1720). See: Superior Court Stipulation for Entry of Judgement. The Farm paid $15,000 in fines, and was required, as part of the settlement, to relocate the composting part of their operation within one year:

"Defendant shall, within a period of one year from the date of entry of Judgement (September 23, 1999), relocate its composting operations from its existing location at 782 Thompson Lane"
BayKeeper letter 10/19/99 -"a pattern of disregard for both California's water quality laws, as well as a chronic disregard of the requirements set forth in the facility's use permit..."
BayKeeper letter 11/1/99 -"Indeed, in my over ten years of advocacy on behalf of the Bay and its watershed, this is the first time I am aware of a local creek being literally cauterized by animal waste."
Hazardous Materials:
The Mushroom Farm is a heavy user of hazardous materials, with an average of 206 pounds per month being applied during a sample period (1/02-3/02).  This includes Diazinon (158 pounds per month), Pounce (4.35 pounds per month), Mertect (19.69 pounds per month), and Benlate (24.6 pounds per month); an average 2479 pounds (about 1.25 tons) of regulated toxics used per year. These figures are documented in records on file with the Sonoma County Agricultural Commissioner, see:Mushroom Farm's monthly Pesticide Report, Diazinon application, December 1998, page 1,Page 2. Note that 180 pounds of Diazinon were applied during this month. Lab tests of Wastewater Pond from 4/6/00, on file with WQCB, show that the wastewater contains 28.2 ug/l  Diazinon. Lab tests of Wastewater Pond from 12/26/01, on file with WQCB, show that the wastewater contains 51 ppb Diazinon. There has been no testing for the other 3 pesticides used by the Farm.
Petaluma Mushroom Farm Odor, as Described by Neighbors
Previous News:
  • January 6, 2003: "Compost permit extension denied, Mushroom grower could face fine for delay... A code enforcement official who visited the farm at 782 Thompson Lane on Thursday found piles of compost...They are not in compliance". See Santa Rosa Press Democrat 1/4/03.
  • July 23, 2002: The Board of Supervisors voted to give the Mushroom Farm its 3rd extension to move its compost (until December 31, 2002). See Press Democrat 7/24/02. Summary of previous deadlines:
    • September 23, 1999: The Mushroom farm was given a one year deadline by Sonoma County Superior Court to relocate its composting operation.
    • September 23, 2000: The farm failed to move its compost by the Court imposed deadline. A one year extension of time to November 1, 2001 was granted, with the stipulation that there be no further extensions, for any reason.
    • January 25, 2001: The Sonoma County Board of Zoning Adjusments voted to modify the Mushroom Farm's use permit to require its compost operation be removed by November 1, 2001.
    • October 25, 2001: The Mushroom Farm failed to remove the compost in accordance the use permit requirement. A one year extension of time to November 1, 2002 was granted by the BZA. The Sonoma County Board of Supervisors later reduced this extension to six months, July 1, 2002.
    • November 16, 2001: The Mushroom Farm failed to remove the compost in accordance with the Court's one year extension. The farm was fined an additional $10,000, and the case was closed.
    • June 10, 2002: The Mushroom Farm failed to remove the compost by the July 1, 2002 extended deadline, and was granted a 6 month extension by the Board of Supervisors until December 31, 2002.
  • June 10, 2002: Roblar Road Project Canceled. The Mushroom Farm announced it will abandon its plans for a second mushroom farm and compost making facility on Roblar Road. The Farm proposes to make compost in Colusa County, and import it to Thompson Lane. See Press Democrat 6/13/02 .
    • "Prohibit the creation of a condition of pollution or nuisance resulting from the management of wastes at your facility. 
    • Nuisance as defined in the California Water Code includes the occurrence of odors resulting from waste management practices which are offensive to the senses, so as to interfere with the public and their comfortable enjoyment of life or property."
  • The Water Quality Control Board has documented new violations by the Mushroom Farm. See: Inspection Report 12/21/01:
    • "Mr. David Cerini (owner/operator) confirmed that the facility was still hauling wastewater to the dairy wastewater holding pond.  Mr. Cerini appeared to understand that he did not have authorization to discharge to the dairy, but indicated that he was continuing to discharge there because he felt that discharging to the City’s treatment plant was cost prohibitive."
    • "the facility's wastewater holding pond is unlined and poses a significant threat to groundwater".
    • required: "installation of a sufficient number of appropriately located, screened and developed groundwater monitoring wells... Groundwater samples from the monitoring wells must be analyzed for the four pesticides used by the facility"
    • "neighbor to the north has stopped using her domestic well due to high levels of nitrogen in the well water." The Lab Report of Well at 1030 Thompson Lane, close to the Petaluma Mushroom Farm's unlined wastewater pond and discharge areas, shows Nitrate contamination of 92 mg/l, double the health standard of 45 mg/l.
    • "During several site inspections, Regional Board staff discovered wastewater and polluted runoff from the facility being discharged directly to Marin Creek."
  • September 23, 1999: the Mushroom Farm settled in Sonoma County Superior Court Case #222564 for of Pollution of a Waterway (Ca. Fish & Game Code #5650a6) and Unfair Business Competition (Ca. Business & Professional Code #1720). The Farm paid $15,000 in fines, and was required, as part of the settlement, to relocate the composting part of their operation within one year. See Baykeeper.
Petaluma Mushroom Farm in the News:

Petaluma Argus Courier July 31, 2002
"a marginal project gone bad." - Duane Butler, engineer hired by the Petaluma Mushroom Farm, describing the Thompson Lane farm at the January 25, 2001 Sonoma County Board of Zoning Adjustments Hearing.

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