Region 8

Intermountain Waste Oil Refinery

Intermountain Waste Oil Refinery site location map Site Type: Final NPL
City: Bountiful
County: Davis
Street Address: 995 South 500 West
ZIP Code: 84010
EPA ID: UT0001277359
SSID: 085G
Site Aliases: Intermountain Oil
Congressional District: 1

What's New?

Updated May 2013

The second five-year review of the remedial actions performed at Operable Unit 1 (OU1) and Operable Unit 2 (OU2) of the Intermountain Waste Oil Refinery began in March 2013. The purpose of a five-year review is to make sure the cleanup actions selected for OU1 and OU2 remain protective of human health and the environment. This five-year review is scheduled to be completed by September 2013.

Ongoing semi-annual groundwater sampling revealed little change in improving groundwater quality. In March 2013, a well centrally located in the contaminant plume was modified to extract greater volumes of the vapor contaminants from the groundwater using a micro-blower powered by a solar panel. This enhanced removal system is referred to as dual-phase. EPA expects this modification to the well to improve the groundwater quality at a low cost. EPA will continue monitoring the groundwater.

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Site Description

The Intermountain Waste Oil Refinery site covers about two acres at 955 South 500 West in a residential/commercial area of Bountiful, Utah. Contaminants such as solvents have been found on the site and have contaminated the groundwater underlying the site. Drinking water has not been affected by this contamination.

A number of different reported operations have occurred at the site, including:

  • The site was originally part of a brick manufacturing facility, encompassing about 20 acres.
  • Handling and refining of waste oil at the site began in 1957 and continued for approximately 35 years before ending in May 1993.
  • In the 1950s, an asphalt business was operating on the site.
  • The Intermountain Oil Company (IOC) operation was originally a trucking business that hauled various petroleum products to customers from the site.
  • The oil blending business commenced in the 1970s.

At the start of the oil blending business, green bottoms (a fraction of crude oil) were blended with diesel fuel and sold for dust control at coal mines. Over subsequent years, used oil replaced the green bottoms and the end product was sold to cement kilns for use as fuel. The used oil was collected from facilities in Utah, Nevada, Idaho, and Wyoming. Waste sludge was reportedly disposed of in an off-site landfill and waste water that may have remained after the treatment process was boiled off at the site. Above-ground tanks used by IOC were located in an unpaved area surrounded by a soil berm.

The business was cited a number of times by the Davis County Health Department and the State of Utah. Neighbors of the site complained of odors and health problems, which they believed were associated with the wastes at the site. The owners took steps to resolve some of these problems. The company forfeited its permit to operate on May 3, 1993.

In 1993, the owners dismantled the refinery and consolidated some wastes into a pile, then covered some of the area with several inches of gravel.

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Site Risk

The site is organized into two Operable Units (OUs). OU1 addresses soils, subsurface soils and potential contaminant sources on site, including tanks, drums and containers; OU2 addresses groundwater.

Under OU1 a human health and screening level ecological risk assessment was completed to determine the risk from soil contamination. The risk assessment determined accumulation of contaminant vapors inside a building constructed on the site would likely create unacceptable risk.

EPA performed a human health risk assessment under OU2 to evaluate potential hazards from exposure to groundwater contamination at the site. The OU2 Baseline Human Health Risk Assessment calculates the risk from three potential exposure pathways:

  • Ingestion of groundwater as a drinking water source.
  • Inhalation of volatile organic chemicals (VOCs) that are released into the air from indoor water uses.
  • Inhalation of VOCs that are released from groundwater and migrate upward through the soil into indoor air.
  • Other possible exposure pathways were judged to be sufficiently minor and quantitative evaluation was not completed.

For each of the above pathways, non-cancer and cancer risk for current or future on-site workers, or future residents was calculated. The only chemical that contributed non-cancer or cancer risk above a level of concern was trichloroethylene (TCE). For non-cancer and cancer risk, the exposure pathway of chief concern is ingestion, with a contribution from inhalation of vapors during water use. Both the non-cancer and cancer calculated risk is only slightly above the values that indicate there could be a potential health impact. Exposure to TCE could cause various health effects depending on the contaminant concentration and length of exposure. Breathing small amounts of TCE may cause headaches, dizziness, lung irritation, poor coordination, and difficulty concentrating. Drinking small amounts of TCE over long periods of time may cause liver and kidney damage, impaired immune system function, and impaired fetal development in pregnant women. The extent of some of these effects is not yet clear.

Media Affected Contaminants Source of Contamination
liquid waste, soil, groundwater solvents petroleum processing wastes

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Cleanup Progress

The site was proposed for listing on the National Priorities List (NPL) in October of 1999 and finalized on May 11, 2000. In March, 2001, the field investigation began. A chronology of milestones follows:

1996 & 1998: The Utah Department of Environmental Quality (UDEQ) conducted sampling on the site. Several solvents (bromochloromethane, 1,1-dichloroethane, and 1,1,1-trichloroethane) were identified in the sump located east of the laboratory, and groundwater samples collected from an on-site monitoring well contained solvents (1,2-dichlorethane, 1,2-dichloroethene, and trichloroethene).

2001: In August, EPA removed and disposed of numerous containers and their contents. The removal included: all the chemicals located in the laboratory building; 55-gallon drums and 5-gallon containers holding various chemical or oily mixtures; two trailer tanks and their contents; the contents of an underground storage tank discovered during the investigation; and contents of the sump stored above ground in the southeast portion of the site. In addition, debris located in various portions of the site was removed. The debris removal included: miscellaneous piping located at various areas around the site; scrap equipment; and empty tanks.

2002: The Record of Decision (ROD) for OU1 was published. The remedy addressed reducing risk from indoor vapors due to soil contamination. It was determined these vapors might pose a health risk for anyone residing in a building constructed on the site. The ROD required any buildings constructed on the site to have a mitigation system that would prevent soil vapors from entering the building. The specifications of this requirement were formalized in a property notice filed with the Davis County Clerk and Recorder's Office.

2004: The Record of Decision for OU2, which outlined the selected remedy, was signed in August. The remedy addressed the groundwater contamination using extraction treatment coupled with Dual Phase Extraction (DPE). Using DPE, both groundwater and soil vapors are extracted and treated from the same well. The remedy combines the two technologies to optimize the effectiveness of the groundwater extraction and treatment of probable contaminant source areas. The Preliminary Closeout Report (PCOR) was signed in October 2006 indicating the completion of OU2 construction.

2006: In February, the groundwater pump and treatment system was shut down after sampling showed TCE remains below the drinking water standard which was the clean up objective. A three month period of groundwater monitoring was conducted to ensure the clean up objective had been achieved. A legal settlement has been reached for the site.

2008: Groundwater monitoring will continue for a period of time to ensure the groundwater contamination remains below the drinking water standards. Additionally, the site was sold in 2006 along with adjacent property. The new owner is working to put the site back into productive use.

Map of former site features and a current aerial view, August 28, 2012

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Community Involvement

Community involvement plays an important role in the Superfund process. EPA uses a number of different tools and resources to promote effective, on-going, meaningful community involvement. The goals of the Superfund community involvement program are to:

  • Keep communities affected by sites informed throughout the cleanup process.
  • Provide opportunities for communities to comment and offer their input about site cleanup plans.
  • Facilitate the resolution of community issues tied to a site.

EPA and UDEQ routinely conduct public meetings, issue fact sheets, and interview citizens to ensure that the community is heard by the regulatory agencies. Community interviews are being conducted during the current five-year review process.

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Bountiful Irrigation supply and design business is evidence of reuse at the IWOR Superfund Site
Reuse at the Superfund site by Bountiful Irrigation

EPA places a high priority on land reuse as part of its Superfund response program mission. The agency tries to select cleanup options that encourage and support future use of a site. EPA uses two fundamental methods to facilitate reuse of Superfund sites:

  • Exploring future uses before the cleanup remedy is implemented, an approach that gives the Agency the best chance of designing cleanup remedies to support the likely future use of a site.
  • Working with landowners and communities to remove barriers not considered necessary for the protection of human health or the environment at those sites where remedies are already in place.

One option for reuse is the siting of clean and renewable energy projects on contaminated (or formerly contaminated) lands. As part of this effort, EPA is evaluating the potential for energy projects on these properties and working with landowners and communities to identify ways to remove barriers to such projects.

In 2006, the property was purchased with commercial use intended. The current owners conducted additional remediation efforts and redeveloped the property for use as an irrigation supply and design business.

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Land Use Controls and Other Institutional Controls

Land use controls are the most common type of institutional control (IC). ICs are administrative or legal controls that help reduce the likelihood for human exposure to contamination. ICs can also help protect the integrity of the remedy. Examples of ICs are:

  • Zoning ordinances.
  • Environmental covenants.
  • Deed notices.
  • Well-drilling restrictions.
  • Building permits.
  • Informational advisories.

Land use controls for Operable Unit 1 require any building constructed on the properties at this site to provide mitigation to prevent soil vapors from entering the building. Any soil excavated during building or other construction will need to be managed appropriately. Other operations will be conducted in a manner that prevents any damage or destruction to any part of the groundwater or soil vapor treatment systems.

Groundwater is currently being treated at this site. Until groundwater meets drinking water standards, land use controls are being used to prevent the installation of a drinking-water well on this property.

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Five-Year Reviews

EPA or the lead agency conducts five-year reviews following the start of a Superfund cleanup when contamination is left on the site. These reviews are repeated every five years. We use these reviews to determine:

  • How the remedy is working.
  • If the remedy remains protective of human health and the environment.

The first five-year review was conducted in 2008. The report of that review is available in Site Documents below. The second five-year review is currently underway.

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Site Documents

You will need Adobe Reader to view some of the files on this page. See EPA’s About PDF page to learn more.

Map of former site features and current aerial view, August 28, 2012

Update to the Five-Year Review, January 2011

First Five-Year Review Report (PDF), September 2008 (72 pp, 8.1 MB)

Update Fact Sheet, October 2006

OU2 Record of Decision (PDF), August 2004 (52 pp, 1.4 MB)

OU1 Record of Decision (PDF), November 2002 (71 pp, 1.3 MB)

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Erna Waterman
Remedial Project Manager
U.S. Environmental Protection Agency, Region 8
1595 Wynkoop Street (EPR-SR)
Denver, CO 80202-1129
800-227-8917 ext. 312-6762 (toll free Region 8 only)

Site Information Repositories:

Davis County Library, South Branch
725 South Main Street
Bountiful, UT 84010

EPA Superfund Records Center
1595 Wynkoop Street
Denver, CO 80202-1129
To request copies of administrative record documents call:
800-227-8917 ext. 312-7273 (toll free Region 8 only)


Tony Howes
State Project Manager
Utah Department of Environmental Quality
Division of Environmental Response and Remediation
195 North 1950 West
Salt Lake City, UT 84116

Dave Allison
State Community Involvement Specialist
Utah Department of Environmental Quality
Division of Environmental Response and Remediation
195 North 1950 West
Salt Lake City, UT 84116

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Photo/Video Gallery

Click on a thumbnail below to view the full size image.

Micro-Blower removes vapor contaminants from the groundwater
Solar panels power the dual-phase Micro-Blower

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Utah Department of Environmental Quality Exit

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