RCRA Part B Hazardous Waste Permit:
Clean Harbors Grassy Mountain LLC

The Grassy Mountain Facility is a commercial, waste, treatment, storage and disposal facility located near Knolls, Tooele County. It is located approximately 80 miles west of Salt Lake City, Utah, in the desert portion of the Bonneville basin near the Grassy Mountains. The site is one square mile in area and is remotely located, 25 miles from incorporated towns or permanent human habitation. It is owned and operated by Clean Harbors.

Because of its desert setting, the site is ideal for land disposal. Annual precipitation averages 6 inches, while the yearly potential evaporation rate averages about 48 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.

A shallow, non-potable aquifer is located in the lake deposits below the site. The depth to the groundwater averages about 17 feet, and the aquifer’s flow is generally west-northwest. Because of high concentrations of dissolved solids (55,000-110,000 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 is capable of managing hazardous wastes, PCB contaminated wastes and oils, industrial wastes and other non-hazardous wastes. The facility can accept liquid, solid or semisolid waste forms for treatment, storage, and/or disposal.

The Grassy Mountain Facility consists of six hazardous waste landfill cells, four PCB landfill cells, one hazardous waste/PCB landfill cell and three industrial waste landfill cells. Three hazardous waste cells and two PCB cells have been closed along with two industrial waste cells. Two hazardous waste cells have reached their permitted capacity and are currently undergoing closure. One TSCA cell and one industrial waste cell have never been used and currently are not permitted.

A release of two low-level organic compounds from Industrial cell 1 was investigated during 1999-2003; a risk assessment concluded that risks to human health and the environment are insignificant (below 1E-6).

The facility was reissued a hazardous waste Part B Permit by the Director of the Division of Waste Management and Radiation Control on September 28, 2012. 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 the violations identified during inspections and the resolution reached.

Clean Harbors Grassy Mountain, LLC phone number is (435) 884-8900.

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.

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