Two chemicals that can lead to major health problems have been detected in the groundwater near city-owned property in downtown Boulder, prompting a monthlong study on how widespread the problem is.
Officials say they don't think the benzene and naphthalene -- common industrial agents -- are threatening the city's drinking water, but they are investigating how and when the chemicals seeped into the groundwater at 1717 15th St.
They are looking into whether the site's history as a coal gasification plant in the early 1900s, or its more recent use as a dry cleaner business, are possible causes of the contamination. Most experts are already pointing to the old gas plant as the likely culprit, which could mean the chemicals have existed underground for decades.
Regardless of the source of the potentially dangerous compounds, Xcel Energy and the city of Boulder have agreed to share the cost of a $30,000 study into the surrounding groundwater as well as the costs of a possible cleanup effort.
While the city manager first publicly acknowledged the problem in a brief memo sent Friday to the City Council, Boulder spokesman Patrick von Keyserling said the city has known about the contamination since mid-2009.
"The city is doing the responsible thing at the moment by investigating the source of the contamination," von Keyserling said.
He said a consultant working for the landlord of the former site of Art Cleaners told officials that benzene and naphthalene had been detected in the groundwater near the building.
Dennie "Chip" Wise, a Realtor who owns the building and hired the consultant, said the chemicals were first discovered in the early 2000s.
"When the Art Cleaners left the building, we required them to do a site analysis, and that's how it came up," Wise said.
It was not immediately clear Monday why the city wasn't alerted sooner about the contamination.
Wise said he's been spending his own money to clean the property since at least the early 2000s and that the work is still ongoing. He said no one from the city has contacted him about the planned study, but he's glad that the city and Xcel are "getting their act together" and looking at the site now.
Benzene and naphthalene have been associated with the dry-cleaning process, but Wise said his consultant believes the spill didn't come from his former tenant.
Art Cleaners' owner Brian Hansen said his company -- which has since moved over one building and no longer has its cleaning operations at the site -- never used the types of cleaning agents that could produce the chemicals that were found.
Walter Avramenko leads the Hazardous Waste Corrective Action Unit of the Colorado Department of Public Health and Environment, which is charged with overseeing the cleanup of hazardous-waste sites across the state. He said the source of the chemicals is more likely remnants of the industrial history of the downtown site.
From 1902 to 1952, the property surrounding 13th Street and Canyon Boulevard was owned by the Federal Gas Co., which operated a coal gasification plant that produced fuel for heaters and lanterns. The plant, which was owned by the Public Service Co. of Colorado, an affiliate of Xcel Energy, was torn down by the early 1960s.
Tom Henley, a spokesman for Xcel, said the company is researching the legal relationship between the former plant and Xcel. But regardless of the history, he said Xcel has committed to paying for half of whatever cleanup -- if any -- is required. Xcel will also pay for two-thirds of the $30,000 testing over the next month.
The company is not, however, admitting liability for the possible contamination by taking on the effort, he said.
Avramenko said the coal-to-gas process resulted in a sludge that often contained benzene and naphthalene, and because the solution was more dense than water, "when it leaks from a containment vessel, it sinks" into the soil.
He said similar spills have been contained to the footprint of the facility that caused it, but it is possible that the chemicals have moved with underground water over time.
Benzene can cause bone marrow to stop producing red blood cells, leading to anemia. It can also damage the immune system or cause cancer.
Naphthalene, which is used in the production of mothballs and has other industrial uses, can lead to anemia, damage to the liver and can cause neurological damage in infants. It's also a suspected carcinogen.
To find out how much of the chemicals are in Boulder's groundwater, and how widespread the chemicals may be, the city plans to begin testing groundwater in the area this week. Denver-based Environmental Resources Management has been hired to perform the series of tests.
The area of the testing will include the parking lot of the city-owned Dushanbe Teahouse and the Municipal Plaza where the Farmers Market is held, according to city officials.
Joe Castro, Boulder's facilities and fleet manager, said the consultant would begin drilling small wells as early as Wednesday. Castro said the work is not likely to affect the Farmers' Market or area businesses.
The results of the tests will help determine whether remediation work is needed, the extent of that work and how much it would cost.
Mark Williams, a water-quality specialist for Boulder County Public Health, said cleanup of the chemicals could consist of pumping up the groundwater, treating it and returning it to the ground.
"It's probably fairly readily treatable," he said, but likely an expensive effort.
Williams said there probably isn't a threat to the city's drinking water supply, but he said it is possible that the chemicals could seep into the nearby Boulder Creek.
From a legal perspective, neither Xcel nor the city may be responsible for cleaning the area because gasification plants from the early 1900s are specifically exempt from the Resource Conservation and Recovery Act that was passed in 1976 and governs hazardous waste.
It's more likely that the property falls under a voluntary cleanup standard, according to state health officials.
Contact Camera staff writer Heath Urie at 303-473-1328, or email@example.com.