The Grassy Mountain Facility is a commercial, waste, treatment, storage, and disposal facility located near Knolls in Tooele County, Utah. It is approximately 80 miles west of Salt Lake City in the desert portion of the Bonneville basin near the Grassy Mountains. The site is one square mile and is remotely located. It is owned and operated by Clean Harbors.
Annual precipitation at the facility averages 6 inches, while the annual potential evaporation rate averages 40 inches. Relative humidity rarely exceeds 10 percent. There are no streams or rivers within a 40-mile radius of the facility; the nearest surface water is the Great Salt Lake, 30 miles to the northeast.
The facility is located on unconsolidated lacustrine sediments and salt deposits from former glacial Lake Bonneville. Depth to groundwater averages 10 feet. Due to high concentrations of dissolved solids (50,000-110,000 mg/L), the groundwater is not suitable for agricultural or domestic uses. Fresh water is trucked to the facility from Grantsville, Utah, nearly 60 miles away.
The Grassy Mountain Facility can manage liquid, solid or semisolid hazardous waste, PCBs, and non-hazardous industrial waste. The Grassy Mountain Facility has three active hazardous waste landfill cells, two of which are also authorized to dispose of PCB waste. There are ten closed landfill cells at the facility – three PCB cells, five hazardous waste cells, and two industrial waste cells.
A release of two low-level organic compounds from Industrial Waste Cell 1 was investigated from 1999-2003. A subsequent risk assessment concluded that risks to human health and the environment from the release are insignificant (below 1×10 -6 ).
The Director of the Division of Waste Management and Radiation Control reissued the facility’s hazardous waste Part B Permit on October 4, 2023.
Note that the online copy is not the official copy. Questions regarding the permit should be directed to the contacts identified below. The Compliance History for Clean Harbors Grassy Mountain lists any violations identified during inspections and the resolution reached.
Clean Harbors Grassy Mountain, LLC phone number is (435) 884-8900.
- Title Page
- Module I—Standard Conditions
- Module II—General Facility Conditions
- Module III—Storage and Treatment in Containers
- Module IV—Storage and Treatment in Tanks
- Module V—Surface Impoundment
- Module VI—Hazardous Waste Landfills
- Module VII—Groundwater Monitoring Protection
- Module VIII—Corrective Action Plan Development Procedures
- Module IX—Post-Closure Plan
- Module X—Waste Management Plan for PCBs
- Attachment II—WAP RCRA-TSCA Waste Analysis Plan
- Attachment II-1—Facility Plan View
- Attachment II-2—Security Plan
- Attachment II-3—Site Inspection Plan
- Attachment II-4—Personnel Training Plan
- Attachment II-5—Preparedness and Prevention
- Attachment II-6-A Contingency Plan Quick Reference
- Attachment II-6-B Contingency Plan
- Attachment II-7—Closure Plan
- Attachment II-8—Supplemental Waste Analysis Plan for F020-F023 & F026-F028
- Attachment III-1—Container Management Building and DFBWO Storage Area Drawings
- Attachment III-2—Policy and Procedures for Managing High VOC Waste Streams
- Attachment IV-1—Tank System & Drawings
- Attachment IV-2 Stabilization Reagent Lists
- Attachment V-1—Surface Impoundment B Drawings
- Attachment VI-1—Surface Impoundment Drawings
- Attachment VI-2–Stormwater Management
- Attachment VI-3–Construction Quality Assurance Plan
- Attachment VI-4–Closure Design and Engineering Report for Cell B/6 and 7
- Attachment VI-5—Design Engineering Report Cells 8 – 13
- Attachment VII-1—Potentiometric/Velocity Map
- Attachment VII-2—Groundwater Sampling and Field Analysis SOP
- Attachment VII-3—Groundwater Detection Monitoring
- Attachment VII-4—Detection/Compliance Monitoring Protocol
- Attachment VII-5–Site Map with Groundwater Wells & Piezometers
- Attachment VII-6—Existing Groundwater Well Specifications
- Attachment VII-7—Statistical Methods for Groundwater Monitoring including Gibbons, 1998
- Attachment VII-8—Annual Measurements of Groundwater Levels
- Attachment IX-A—Site Post-Closure Inspection Plan
- Attachment IX-B–Post Closure Inspection Forms
- Attachment X-1—PCB Training Manual
- Attachment X-2—PCB Tank Management
- Attachment X-3—TSCA Inspection Forms
- Attachment X-4—Spill Prevention Control & Countermeasure (SPCC) Plan – TSCA
- Attachment X-5—TSCA/PCB Coordinated Approval: Cell B6
- Attachment X-6—Coordinated Approval B6 Expansion
- Attachment X-7—Coordinated Approvals Cells B6 & 8
- Attachment X-8-Original 1990 TSCA Application – Chapter 4 (Closure Plan)
Comments or Questions
If you have any questions concerning the permitting or compliance of Clean Harbors Grassy Mountain Facility, please contact Kari Lundeen (klundeen@utah.gov) (385) 499-4923.