Goose Lake Road dump story has happy ending

About 3,200 tons of debris and contaminated soil have been excavated and removed from an old dump found during roadwork along Goose Lake in the Elm Creek Park Reserve.

A $735,000 Hennepin County grant was used to remove contaminants this fall and to reconstruct the steeply sloping Goose Lake shoreline. Special synthetic fabric was used to hold the bank.

A road construction crew found the former dump last year under part of a mile stretch of Goose Lake Road that was rebuilt north of 109th Street along the Champlin-Dayton border. The dump extended from under Goose Lake Road into a steep bank by the lakeshore.

The dump appeared to be from the early 1900s and consisted of mostly glass and metals with lesser amounts of wood, pottery, vehicle batteries and shingles. The dump materials were found to be contaminated with mercury, arsenic, cadmium, lead, selenium, petroleum and asbestos, county officials said.

"The extent and level of contamination turned out to be less than what we initially thought. A lot of material had contaminant concentrations that were not very high," said John Evans, a senior environmentalist for the county. "The hot spot was the mercury."

Tests found mercury at levels considered unsafe, though not hazardous, by the state Pollution Control Agency. Debris or soil with the mercury at that level is barred from Minnesota landfills, so about 750 pounds of mercury-polluted soil was sent to a landfill in Lake Mills, Iowa, Evans said.

The Three Rivers Park District, which runs Elm Creek, sampled nearby sediment in Goose Lake but found "no indication of impact from the dump, so no lake cleanup was needed," Evans said.

Most of the dump had lower-level contamination that can be accepted by Minnesota landfills, Evans said. He said samples taken from the clayish soil under the dump showed no significant pollutant leaching.

"I think it was a good example of various agencies working together to deal with an old contamination issue that could have impacted the lake, but luckily it didn't," Evans said. He said removing the contaminants took about two weeks, but restoring the road slope to the lake took several months.

Cleanup costs are being tabulated, but it looks like the price may be about $100,000 less than the $735,000 county grant, he said. It was the largest of $2.4 million in grants made this year from the county's Environmental Response Fund.

The grants, funded by a county mortgage registry and deed tax, pay for assessment and cleanup of polluted sites. Priority is given to projects involving green space, affordable or moderately priced housing, and economic development.

Jim Adams • 612-673-7658