State ready to dig in at Washington County landfill

Call it the big dig.

State officials have elected to clean up a Washington County landfill that's releasing toxic gases and polluting area groundwater by digging out the waste, lining the landfill and then burying the waste again.

The project will start later this summer and is expected to take three years. Its cost is estimated at $27.6 million, making it the most expensive landfill cleanup in the history of Minnesota's landfill remediation program.

From 1969 to 1975, Ramsey and Washington counties used the 35-acre landfill, in Lake Elmo, as a garbage disposal site.

3M Co. also used the site to legally dump materials, including the chemical PFBA, a coatings compound used in photographic films and other products.

In the past year or so, the Minnesota Pollution Control Agency (MPCA) has been weighing several options to clean up the site.

Recently, agency officials chose the dig-and-line approach, over the objections of some Lake Elmo citizens and city leaders. They had lobbied for removing the waste permanently, either by hauling it away in trucks to a different landfill or by incinerating it on site using a futuristic technology called plasma-torch incineration.

In addition, 3M has agreed to contribute $8 million.

"The cost of moving a landfill of that size could obviously be done at some point, but it may have taken years to secure the funding," she said. "It came to a point of balance, of making sure this issue was addressed as quickly as possible."

State Rep. Julie Bunn, DFL-Lake Elmo, the other co-author, said a provision in the law requires the MPCA to use a triple liner in the landfill for added protection against leakage.

Right now, the landfill is covered but not lined, said Peter Tiffany, a senior engineer with the MPCA. Typically, the agency uses a double-layer lining.

Tiffany said the cleanup will be in three phases. The plan is to first dig a hole into fresh soil and start installing a liner. Then workers will move the waste from the existing landfill into that liner. The waste that has just been removed will free up more land in the landfill and an additional liner will be installed, and more waste will then be removed.

"This is by far the biggest project we've done," he said.