The Alaska Department of Transportation and Public Facilities has opened bids for restoring the pavement on the Sterling Highway through the center of Soldotna.

The project, estimated to cost between $2.5 and $5 million, will grade and resurface the Sterling Highway between approximately one-third of a mile south of the Kalifornsky Beach Road intersection and Devin Drive near Fred Meyer. Drainage, signals and curb ramps will be improved as well, according to the project plans.

The contractor will use a stronger type of pavement called hard aggregate that is meant to last longer, although it is more expensive. Traffic signals will also be more responsive to cars after their loop detection signals are replaced.

Although the project is scheduled to take place during the summer, when the highway sees some of its peak traffic, most of the work will take place at night. Traffic cannot be restricted between 6 a.m. and 8 p.m. from Monday through Sunday, near holidays and during the Kenai River Festival and the dipnet fishery.

The project does pass near several contaminated sites in the Soldotna area: The River Terrace RV Park site, the Soldotna “Y” Chevron site and the Cornerstone Marketplace site, all indexed by the Alaska Department of Environmental Conservation as polluted sites.

The Cornerstone Marketplace site is not much of a risk for the project — the contaminated soils, leftovers from an old undocumented sewage pipe, are about 20 feet underground, according to the Erosion and Sediment Control Plan for the project.

However, the other two sites are closer to the surface. The Soldotna “Y” Chevron site, which is contaminated with leftover petroleum from the removal of gas tanks, is closer to the surface and could interfere with the project, according to the plans.

The River Terrace RV Park site, which is on the northeast side of the bridge in Soldotna, is contaminated with tetrachloroethylene — widely used for dry cleaning — in two plumes. One of the plumes migrates toward the Kenai River, and the other toward the road, where it may interfere with the project.

The likelihood of hitting these sites during the project is fairly low — most of them are deeper beneath the surface, and the only excavating work required is for drainage. However, if the contractor does hit one of the contaminated sites, they will have to stop the project and call the Department of Environmental Conservation, said Kristen Kiefer, a project manager with DOT.

Although the contractor may not know if they hit a contaminant, the state has inspectors on site to make sure the contractor is following the specifications and he or she can help identify a problem if one arises, she said.

“Sometimes you’ll see a sheen on the water from oil,” Kiefer said. “But usually it’s the smell with these diesel sites.”

The project is slated to be complete by October 2016. Bidding ends Dec. 11.

Reach Elizabeth Earl at elizabeth.earl@peninsulaclarion.com.