Mule Creek State Prison Compliance Issues and Regulatory Strategy

Facility Background and Overview

The Mule Creek State Prison facility (MCSP) is owned and operated by the California Department of Corrections and Rehabilitation (CDCR). MCSP is located approximately 1 mile west of the City of Ione, California, and approximately 10 miles west of the City of Jackson. Mule Creek runs through the center of the facility.

The Central Valley Regional Water Quality Control Board (Central Valley Water Board) regulates the operations that occur at the MCSP facility with several water quality permits. Each permit has prohibitions, conditions, and requirements to operate and monitor the covered component such that beneficial uses are not impacted, and environmental health is protected:

  • The wastewater collection system is regulated under the Sanitary Sewer System General Order (SSO General Order), Water Quality Order No. 2006-0003-DWQ.
  • The wastewater treatment plant, effluent storage reservoir, and on-site land application areas are regulated by the Waste Discharge Requirements (WDRs) Order R5-2015-0129 from the Waste Discharge to Land Permitting Program.
  • The storm water discharge to Mule Creek is regulated under the National Pollutant Discharge Elimination System General Permit for Waste Discharge Requirements for Storm Water Discharges from Small Municipal Separate Storm Sewer Systems (MS4), WQ Order 2013-0001-DWQ, as amended (Small MS4 General Permit).
  • CDCR has also submitted a No Exposure Certification for the Industrial Stormwater General Permit (IGP).

The scope, primary concerns, and compliance strategy of each of these permits is described in the modules below, along with links to the program pages, permits, associated monitoring reports, enforcement actions, and program links.

Waste Discharge to Land Requirements

WDRs Order R5-2015-0129 defines the requirements, prohibitions, monitoring, and reporting associated with the wastewater treatment plant, effluent storage reservoir, and on-site land application areas. A blend of domestic and industrial wastewater is generated, treated, and disposed of at MCSP. Currently, MCSP houses approximately 4,000 inmates and employs 1,250 CDCR staff full time. MCSP generates an unknown volume of industrial waste from several industrial operations, which is discharged to the sanitary sewer system. These operations include a coffee roaster, meat processor and smokehouse, textile manufacturing operation, and a large-scale laundry operation that serves several other prisons across the state. In addition, MCSP receives an unknown amount of domestic waste flows from the California Department of Forestry Fire Academy and a small amount of wastewater from the closed Preston Youth Authority facility, both located adjacent to MCSP. These wastewater flows are combined and treated at the on-site wastewater treatment plant. Secondary disinfected effluent is stored in an effluent reservoir and disposed of the on-site land application areas, an effluent storage reservoir, or Preston Reservoir. CDCR has also built and periodically operates an effluent export pipeline to discharge effluent to the City of Ione tertiary plant for further treatment and irrigation of the Castle Oaks Golf Course. This off-site beneficial reuse is not described or permitted in the current WDRs.

Compliance Concern Strategy to Return to Compliance
Insufficient flow and composition data to determine threat to water quality and public health posed by the treatment and disposal of the industrial wastewater Revised Monitoring and Reporting Program (MRP) R5-2015-0129 was issued in October 2021 to require monitoring necessary to collect needed data. Based on that data, the WDRs will be updated to ensure beneficial uses are protected. Data will also be sent to the County to make public health recommendations.
Lack of treatment process for industrial waste Future WDRs will be developed using the data on the industrial waste stream collected under Revised MRP R5-2015-0129 and will include requirements and upgrades to the treatment train as needed to address industrial waste constituents.
Insufficient wastewater effluent disposal capacity The current WDRs require CDCR to develop additional disposal capacity to make up for the increased prisoner population and loss of spray fields caused by the 2015 prison expansion. However, the disposal plans of Sutter Creek and the City of Ione will change drastically in July 2022. Therefore CDCR, Ione, and Sutter Creek will be required to submit water balances consistent with each other to determine the disposal deficit.
Overloading of specific spray fields potentially causing subsurface seepage into Mule Creek Symptom of insufficient disposal capacity, see above.
Nitrate and VOC impacts to groundwater Symptom of insufficient disposal capacity, see above.

Land Discharge Waste Discharge Requirement (WDR) Permit Documents

Recent Enforcement Documents

  • 23 September 2020 Notice of Violation (will provide document, is not currently online)

Monitoring Reports

Please contact us for copies of these documents.

  • Monthly Waste Water Treatment Plant Reports required by WDRs (will provide document, is not currently online)
  • Quarterly Groundwater Reports required by WDRs (will provide document, is not currently online)
  • Annual Reports required by WDRs (will provide document, is not currently online)

Small Municipal Separate Storm Sewer System (MS4)

On 28 December 2017, Central Valley Water Board staff received a complaint of ongoing illegal discharge of wastewater from an unknown source into the storm water system and subsequently into Mule Creek. In response, Central Valley Water Board staff inspected MCSP on 4 January 2018 and collected samples. The results indicated that the discharge exhibited the characteristics of domestic and industrial wastewater, and exceeded several applicable regulatory limits, resulting in the issuance of a Water Code Section 13267 Order (13267 Order) on 14 February 2018. As part of the 13267 Order, CDCR completed monitoring and an investigation of the storm water and sanitary sewer systems to determine the source of the waste. It determined that both systems had numerous defects allowing liquid to infiltrate and ex-filtrate and that groundwater was mounded beneath MCSP as a result. CDCR’s Investigation Findings Report and Central Valley Water Board Staff’s Review Memo for that report are linked below.

During the investigation, Central Valley Water Board staff determined that the storm water system at MCSP may pose a threat to water quality and storm water discharges from MCSP should be regulated under the Small MS4 General Permit. On 8 February 2019 the Central Valley Water Board adopted Resolution R5-2019-0006 designating MCSP as a Non-Traditional MS4, and on 10 April 2019 MCSP was designated as a Regulated Small MS4 by the State Water Resources Control Board (State Water Board). The Small MS4 General Permit requires CDCR to develop and implement a storm water control program for MCSP to reduce the discharge of pollutants from its MS4 to Mule Creek and ensure compliance with applicable water quality requirements. Due to potential water quality impacts to Mule Creek while the MCSP storm water control program is being fully developed and implemented, and to ensure compliance with the Small MS4 General Permit requirements, the Central Valley Water Board determined that an interim monitoring and reporting program is necessary to monitor MS4 discharges from MCSP to Mule Creek. The Central Valley Water Board issued a 13383 Order to perform monitoring and reporting on 6 August 2020. The 13383 Order was initially updated on 16 December 2020, followed by an additional update on 30 November 2021.

On 18 February 2021, the Central Valley Water Board approved Settlement Agreement and Stipulation for Entry of Administrative Civil Liability and Administrative Civil Liability Order (Stipulated Order), Order No R5-2021-0001 regarding the unpermitted discharge of co-mingled storm water and wastewater to Mule Creek from the MCSP MS4. The scope of the Stipulated Order only included discharges occurring between the discovery of waste constituents in the discharge by Central Valley Water Board staff on 18 January 2018 and 10 April 2019, which is when MCSP enrolled in the Small MS4 General Permit. As part of the Stipulated Order, CDCR agreed to defer funds from the penalty amount to the following Enhanced Compliance Actions (ECAs): a Landscape Irrigation System Replacement Project to repair broken landscape irrigation pipes that are contributing to excessive dry weather flows into the MS4 and a microbiological study (Microbial Study) performed by the Southern California Coastal Water Research Project. The Landscape Irrigation System Replacement Project is expected to be completed in March 2025. The Microbial Study is complete but unfortunately was not performed with EPA-certified methods and was mostly inconclusive, although human biomarkers were detected in Mule Creek.

Compliance Concern Strategy to Return to Compliance

Insufficient flow and composition data to determine threat to water quality and public health posed by the discharges to Mule Creek from the MS4

The updated 13383 Order requires the collection of monitoring data needed to determine the threat to water quality and public health posed by MS4 discharge. The Small MS4 General Permit requires CDCR to address any illicit discharges occurring to the system once they are found.
Discharges from the MS4 have been occurring during long periods of dry weather As part of the 2021 Stipulated Order, CDCR is required to repair the landscape irrigation system. In addition, Central Valley Water Board staff reviewed CDCR’s Non-Storm Water Discharge Report and determined that the irrigation runoff from defects in the irrigation system does not meet the Small MS4 General Permit’s definition of incidental runoff. As required by the Small MS4 General Permit, CDCR submitted a Non-Storm Water Discharge Elimination Plan (NSWDE Plan) to eliminate the non-storm water runoff. This NSWDE Plan is currently under Central Valley Water Board staff review.
The Stormwater System Investigation Findings Report (Report) detailed numerous defects and locations of infiltration in the MS4 system The Report concluded that there are defects in the sanitary sewer and irrigation systems and MS4. For Non-traditional MS4s, the Small MS4 General Order requires that illicit discharges into MS4 be corrected once the source is identified.

Enforcement Documents

  • 14 February 2018 13267 Order (will provide document, is not currently online)
  • 1 November 2019 Stormwater Investigation Findings Report (will provide document, is not currently online)
  • 7 December 2020 Stormwater Investigation Findings Report Review Memo (will provide document, is not currently online)
  • 18 February 2021 Settlement Agreement Administrative Civil Liability Order R5-2021-0001
  • 18 February 2021 Board Presentation for ACL Adoption (will provide document, is not currently online)

Monitoring Reports

Industrial Stormwater General Permit (IGP)

CDCR filed a No Exposure Certification (NEC) on 22 May 2018, which certifies that all industrial activities occur indoors and therefore they should be exempt from certain Industrial Stormwater General Permit requirements. Stormwater staff inspected the facility on 27 January 2021 and determined that the NEC is applicable here. Therefore MCSP is not regulated under the IGP.

SSO General Order

On 2 May 2006 the State Water Board adopted the SSO General Order, Order No. 2006-0003-DWQ. This Order requires all federal and state agencies, municipalities, counties, districts, and other public entities that own or operate sanitary sewer systems greater than one mile in length and collect and/or convey untreated or partially treated wastewater to a publicly owned treatment facility to enroll and comply with the requirements described within.

As part of previous enforcement actions taken by the Central Valley Water Board for wastewater spills from the collection system to Mule Creek MCSP, CDCR was enrolled in the SSO General Order on 5 December 2014. The Order includes requirements for the maintenance, monitoring, and repair of the sanitary sewer system. Based on the 1 November 2019 Stormwater Investigation Findings Report, adequate maintenance and repair have not been performed, and the Board is evaluating enforcement.

Compliance Concern Strategy to Return to Compliance
The Stormwater System Investigation Findings Report detailed numerous defects and locations of infiltration in the storm water collection system Board staff is reviewing the most recent Sanitary Sewer Maintenance Plan and will provide formal communication to CDCR stating how to address these issues and come back into compliance with the SSO General Order.

SSO General Order Permit Documents

Sanitary Sewer Management Plans (SSMP)

  • 2020 SSMP (will provide document, is not currently online)

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