(The following article by Gordon Weixel was posted on the Bismarck Tribune website on February 18.)
BISMARCK, N.D. — BNSF Railway has ended its contract with Thermo RETEC for remediation services following settlement of a case by the state of North Dakota against the railroad for diesel fuel contamination of Mandan property.
According to BNSF Railway spokesman Gus Melonas, RETEC has been working for BNSF since 1998 in an effort to remove and rehabilitate soil contaminated by the fuel oil. Last year the state was awarded $30.25 million, $24 million of which was used to create the Mandan Remediation Trust. The city of Mandan has hired Leggette Brashears & Graham to clean up the fuel contamination, a process they began last fall with a survey of property owners. Cleanup operations will begin in earnest this spring.
“BNSF will continue to monitor conditions and take appropriate actions in cooperation with the state,” Melonas says. “The downtown property, city and privately owned, now has the jurisdiction to manage the cleanup per the settlement agreement. BNSF is cooperating with state requirements.”
RETEC’s Kurt Geiser, contacted at the company’s St. Paul, Minn., offices, had little to say about the end of its contract with BNSF other than RETEC’s accomplishments are a matter of public record.
RETEC is one of five companies BNSF has contracted with to remove fuel. The problem was first discovered at the site of the Law Enforcement Center in 1984. Other companies engaged to remove the diesel fuel were Soil Exploration Co. Inc. (1984-86), Earth Resource Technologies (1986-89), John Mathes & Associate Inc. (1989-91) and Radian Corp. (1991-98).
According to the North Dakota Health Department’s Scott Radig, about 100,000 gallons of fuel were recovered by RETEC using the trench recovery system from 2000 to 2004.
“Recovery rates were good when the system started in 2000, and 52,000 gallons of fuel were recovered by the end of 2001,” Radig said. “Recovery rates declined in 2002 and 2003, with approximately 25,000 to 30,000 gallons and 15,000 to 20,000 gallons of fuels recovered each of those years. The trench recovery system was discontinued in September 2004.”
RETEC’s pullout wasn’t unexpected, according to Mandan City Administrator Jim Neubauer. “They’ve been working strictly for BNSF,” he said. “We’d expected them to leave since, as part of the settlement, the city will be taking care of the problem.”
“I think they’ve roughly recovered 600,000 to 700,000 gallons of the free product from underground,” Neubauer added. “But the great unknown is, how much remains underground? We’re still finding free product in monitoring wells around town.”
Neubauer said RETEC used a process, the trench recovery system, by which they attempted to lower the ground water, which was treated and then pumped into the Heart River. An underground trench would be created where the fuel oil would concentrate and a belt skimmer was employed to which the petroleum free product would stick and be brought to the surface.
“They were using 11 belt skimmers in structures located on BNSF property on the south side of Main Street, but recently, only two or three were recovering any product. We know the aquifer is huge and they were pumping and treating about 2.5 million gallons of water a month.”
In 1987 ERT Inc. pulled 102,459 gallons of the fuel from the ground and followed that with 85,070 in 1988. From 1987 to 1994, more than 390,000 gallons were removed, then in 1995 only 1,694 gallons were recovered, followed by: 1996 — 2,936 gallons; 1997 — 8,421; 1998 — 4,167; and 1999 –10,466.