HILL AIR FORCE BASE — A whistleblower's claim that a 2007 spill of more than 60 pounds of mercury was not properly reported or cleaned up at this military base, where more than 24,000 military personnel and civilians work and live, has prompted a federal criminal investigation.

The Utah Department of Environmental Quality has backed up that claim, concluding after an investigation in September and October that the base violated permits because it failed to report the spill and cleanup, improperly stored the cleaned-up material, improperly labeled storage containers that were also not in good condition and failed to inspect containers storing the hazardous waste.

Base officials on Wednesday said they were preparing a public response to claims by the whistleblower and DEQ.

Scott Anderson, DEQ director of solid and hazardous waste, said the Environmental Protection Agency is also conducting a criminal investigation. The DEQ sent a notice of violations to the base in a March 2 letter, requesting a response by April 2.

The DEQ letter puts the base on notice that it could face civil penalties of up to $13,000 per day. Anderson said actual penalties would be negotiated with base officials later but  the clock on the potential for penalties began ticking when the spill occurred five years ago.

There are additional steps in the investigations, and any finding on penalties is a ways off. "We're not even close that yet because we haven't gotten their official response."

Salt Lake attorney Scot Boyd is representing the unidentified whistleblower, who is described as a former base employee.

Boyd said the Department of Defense and Department of Justice are also investigating, and said his client is protecting his identity because he is concerned about retaliation against family members who still work on base.

Boyd said that Hill workers in 2007 removed more than a dozen mercury-containing ring balance meters from boilers that were placed outdoors on pallets, and that the meters began leaking liquid mercury onto the ground. Patent documents describe a ring balance meter as a device for measuring fluid pressures.

"More than 60 pounds of mercury was spilled. As noted on the DEQ website, any time one pound or more of liquid mercury is released to the environment, the spiller must call the National Response Center," Boyd said, and that untrained workers used vacuum cleaners to try and clean the area.

"Workers were unable to recover all of the liquid mercury," Boyd said. "One of the questions that is still unanswered is whether they recovered all of the liquid mercury, and if not, where it is or how it was disposed of."

Mercury, a liquid at room temperature, is exceptionally dense, and 60 pounds would equal slightly more than one-half gallon, by volume.

Anderson said the DEQ's investigation has not corroborated the claim that 60 pounds of mercury was spilled. "I expect the containers may have held that much, but to say that much was spilled, I'd guess it was a lot less than that."

The whistleblower cooperated in the investigation, which started with the EPA, Anderson said. A call to the EPA investigator has not been returned.

"The stored mercury was recovered and steps were taken to protect the health of the military personnel and civilians at Hill AFB and the general public," Boyd said.

Anderson said Hill does have hazardous materials storage areas that are approved by permit, and that the recovered mercury has since been moved to approved storage areas on base.

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