The Burley Products Terminal is located along State Highway 81 about four miles east of Burley, Cassia County, Idaho. The Terminal is comprised of three adjacent properties owned and operated separately by Tesoro West Coast Company (formerly Amoco Oil Company) at 421 East Highway 81, Chevron Pipeline Company at 423 East Highway 81, and Sinclair Oil Corporation at 425 East Highway 81. Tesoro owns and operates a bulk fuel distribution facility with four large above-ground storage tanks and a loading rack for distribution to petroleum tank trucks. Sinclair owns and operates a bulk fuel distribution facility with seven large above-ground storage tanks and a loading rack. Chevron Pipeline Company owns a property between Tesoro and Sinclair where there was at one time above ground petroleum storage tanks, and they own the pipeline which supplies the Terminal and bisects the site. These three companies are known collectively for the purposes of this cleanup as the Burley Terminal Operators (BTO).
Approximately 500 feet to the north of the Burley Products Terminal is the Snake River. The Snake River is a "navigable water" of the United States. In 1974, petroleum was observed seeping into the Snake River immediately to the north of the Terminal. Petroleum seeps to the Snake River were also reported to the National Response Center in 1999 and 2000. The seep occurrences of 1999 and 2000 were noted during a time of abnormally low river water elevation, and were observed below the normal river water surface level.
There has historically been significant on-site contamination of soils and groundwater at the Burley Products Terminal. Investigation of groundwater hydrology at the site indicates that the predominant direction for flow of groundwater is in a northerly direction from the Terminal towards the Snake River. Petroleum compounds in groundwater and free phase product have been documented in both shallow and deep water bearing zones between the Terminal and the Snake River.
In October of 2001, the BTO jointly entered into an Administrative Order on Consent with EPA (Docket #CWA-109-2001-0200) to investigate and cleanup petroleum contamination causing discharge or threat of discharge to the Snake River. In accordance with the Order, a combination soil-vapor extraction/air sparging system was installed and has been in continuous operation in the western bench part of the site since January 2003, and in the eastern bench part of the site since August 2004, to remove petroleum contamination in upland soils and groundwater contributing to the seep.
In 2003, the BTO, through its contractor Maxim Technologies, performed sampling of beach and river bottom sediments to define the vertical and lateral extent of petroleum impacted soils and sediments capable of producing sheen on the Snake River. In November 2005, the BTO conducted removal of contaminated sediments at former seep areas along the Snake River, at a time when the River level was lowered to expose most of the contaminated area.
On November 4, 2005, BTO's contractor Maxim Technologies and their construction subcontractor, Northwest Technologies, mobilized to the site to begin the beach area cleanup phase of the overall project. Prior to that, Maxim had prepared, at the request of the EPA OSC, a Biological Assessment per the requirements of the Endangered Species Act, which was reviewed by the U.S. Fish and Wildlife Service. As a result it was determined that the proposed removal action was not likely to harm endangered species or critical habitat. Additionally, coordination was done with the U.S. Army Corps of Engineers with respect to use of the Clean Water Act Nationwide Permit #20.
The removal action was timed to correspond with a drawdown of the Milner Reservoir on the Snake River, where the site is located. The drawdown this year was greater than normal; approximately 6 feet below the usual high water level, which exposed all but a small portion of the contaminated area requiring excavation.
From November 4-12, 2005, the area was cleared, silt fence installed, and an access/haul road was constructed on property owned by Sinclair, from the top of the bluff down to the river level west of the western seep area. Using clean "pit run" fill material, a roadway was then constructed east on the exposed beach approximately 1,200 feet to access the eastern seep area.
From November 17-19, the eastern seep area was excavated. Approximately 87 cubic yards of contaminated sediments were removed. All of the work at the eastern seep area was done above the water level. There was no observed sheen or discharge to the Snake River. Also during this time, a coffer dam was constructed at the western seep area to expose a small portion of the contaminated sediments requiring excavation that would otherwise still be under water. The coffer dam was constructed by filling an elongated rubber liner with gravel and wrapping the liner, burrito style, around the gravel fill. The coffer dam extended only about 15 feet into the river, and maximum water depth was about 2 feet. Linear extent of the coffer dam was about 350 feet. Water inside the coffer dam was sampled. Laboratory results indicated all BTEX constituents below drinking water standards, and the water was subsequently pumped back into the River.
From November 21-29, the western seep area was excavated. Approximately 1375 cubic yards of contaminated sediments were removed. All removed material was taken to a DEQ approved land farm located just across Highway 81, at the southeastern corner of the Sinclair Burley Products Terminal property. Soils excavated below the normal water line, in the coffer dam area, were stockpiled on the beach to allow dewatering before transport to the land farm. Water that accumulated inside the coffer dam was pumped into a frac tank. This water was sparged for several days and then sampled. Analytical results indicated that BTEX constituents were below drinking water standards, and the water was discharged to the River. Excavated areas were backfilled with clean "pit run" material. The coffer dam and beach road were removed, and personnel and equipment demobilized by 11/29/05.
The BTO will submit for review a Final Report per the requirements of the Consent Order.
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