Source: http://siouxcityjournal.com, May 9m 2015
By: Bret Hayworth
State and local officials are looking for a new solution to the old problem of groundwater and soil contamination at the Woodbury County Law Enforcement Center.
The building, at 407 Seventh St., is on the site of a former gas station. The contamination was believed to have been adequately addressed when an air filtration system was installed in the building in 2003. But it has shown up again in recent testing.
After years of regular tests to ensure that existing levels of hazardous chemicals don’t pose a health risk, a sample taken late last year has raised concerns, said county Human Resources Department Director Ed Gilliland.
The sample, taken by consultant Northwest Environmental Services, of Alton, Iowa, and sent to the Iowa Department of Natural Resources, showed higher levels of benzene than had been seen previously. The amount was below statewide target levels, said DNR Environmental Specialist Matthew Graesch. County and state officials now are looking hard at the site.
The state agency has been doing twice-yearly testing of wells under the facility. All along, there have been substantial amounts of petroleum floating on top of the water under the building. The goal is to ensure that petroleum vapors won’t get into the facility, Graesch said.
The tests have been to check for chemicals such as benzene, which can damage the immune system or cause poisoning.
“Things aren’t necessarily getting worse, but (tests are) showing that it isn’t going away by itself. So we’re going to take an active role rather than a passive role,” Graesch said.
The building holds the jail, Sheriff’s Office quarters and courts. Sheriff Dave Drew and 3rd District Court Administrator Leesa McNeil said late last month they had not noticed any petroleum odors and that no employees had complained of symptoms.
A crew in April drilled holes around the building as a first step in designing a better solution for the property. Details about possible plans will be aired Thursday when the DNR meets with county officials.
“The situation is in pretty good control at this point,” Gilliland said. “The DNR has their nose right on it. They’ve got the expertise.”
Drew said the fact that problems keep popping up is a concern. He’ll remain skeptical until the May discussions play out.
“The question is, what if it isn’t OK? Does it make me feel better? No, it makes me concerned,” Drew said. “We just want to make sure everything is good here.”
Graesch said relatively dry conditions in 2012 and 2013 years made the petroleum more likely to move underground.
“It may have remobilized,” Graesch said.
Graesch said when the jail was built, officials didn’t take the usual step of carting away soil from the former gas station.
Building Services Director Mark Elgert said the existing filtration system is designed to pull more fresh air into the LEC. If benzene is detected, a series of exhaust fans kicks in.
That system was added after workers in the early 2000s complained about petroleum-like odors in the building’s basement. Environmental studies showed the odor was caused by benzene fumes.
The county was reimbursed for nearly all of the $240,000 paid for contamination cleanup in 2003. The reimbursement came from the Innocent Land Owners Fund, a pool of money collected by the state from petroleum companies.
Gilliland said similar ongoing cleanup issues occur on other old gas station properties. Another is in the 300 block of South Floyd Boulevard.
Gilliland said if more equipment is needed for a fix, it will be added this year. Any costs to the county would again come out of the Innocent Land Owners Fund.
Gilliland, Graesch and Woodbury County Board Chairman Mark Monson said aggressive action will be taken this year to address any problems.
“It is a safe place to work and will continue to be,” Monson said.