Semi-truck traffic will be restricted in the alley next to the City Hall and parking garage construction site. 

“We’re keeping semis out as a precaution,” said Mike Cronquist, the city’s representative on the project. “We’re going to expedite the work on the foundation along the alley so we can have better access.”

The north and south ends of the alley will remain open for deliveries to businesses along the alley, but no through traffic will be allowed.

Cronquist estimates the closure will remain in effect for four to six weeks. Martel Construction will work to accommodate deliveries in the alley, Cronquist noted.

Concrete work on the project continues with pouring the foundation and basement for City Hall. Work is shifting more toward site prep and concrete pouring on the parking structure portion of the project. Recent drier conditions have improved the ability to pour concrete.

“Concrete is on an upswing with more and more happening,” Cronquist said. “We will be pouring something one to two times per week.”

Areas of contamination on the site have been contained. About 100 cubic yards of material was removed and is being tested to confirm that it is hydrocarbons. The city believes the contamination likely came from underground fuel storage tanks that were located across the street years ago when a gas station operated there.

The area was dug below grade and then sealed off, according to Cronquist, and an under-slab vapor removal system will be installed at the site.

The city’s consultant Applied Water Consulting, along with the advice of the state Department of Environmental Quality, recommended installing the system, which consists of a perforated piping grid to allow for removal of any residual vapors that may be left in the existing soils.

“It’s a precautionary measure at the recommendation of our consultant,” Cronquist said. “Contamination in the soil can take a long time to move and the cap will seal it off so it doesn’t go anywhere.”

The cost of removing the contaminated soils and installing vapor removal system is still being worked on with Martel Construction, according to City Manager Chuck Stearns.

An underground tank that once stored heating oil for the former City Hall was previously found and removed at a cost of $20,000.

The budget for the City Hall and parking garage is just over $16 million.