An old oil tank buried under concrete was found to have contaminated soil under the old Co-op building.
“The tank had leaked over a period of time into the soils below,” said the city’s director of development services Marvin Kwiatkowski in an e-mail.
Test results show the tank’s contents were a diesel-like product. While much of the soil has been pulled to the top to aerate, more soil is expected to be excavated.
“We plan to excavate more contaminated soil, store on-site for a short time (up to one month) and then transport to Hazco’s soil remediation cells at the Terrace landfill,” said Kwiatkowski. “Treatment of the soil would be done by Hazco.”
The city of Terrace had set aside $47,400 in the co-op demolition budget to deal with unforeseen circumstances like this, he said.
The initial consultation fee is estimated to be $5,000, said Kwiatkowski, adding he’s not sure what the final cost to the city will be to deal with the soil. The tank was discovered in early November buried under nine feet of soil and concrete floor, and had small holes around the middle.
Kwiatkowski said it likely dates back to the 1940s when this type of tank was used to heat buildings and homes.
“The underground storage tank was likely used to heat one of the original buildings on the site,” he said. “It is likely the tank has not been in use since the 1960s.”
It was not found during initial ground penetrating radar tests because it was buried under concrete, said Kwiatkowski.