Delaware Department of Transportation has agreed to clean up the rail bed before beginning work on Milton’s Rails to Trails extension.

Under a voluntary cleanup program prior to beginning work on the trail extension, DelDOT spokesman C.R. McLeod said, “We execute a volunteer cleanup agreement with DNREC on every railroad project we do. It allows us to determine if any impurities exist in the ground and if so, to what levels. It also allows us to determine a remedial path forward.”

McLeod said DelDOT has not heard of any problems so far and does not anticipate any delays in the construction schedule.

McLeod said barring last-minute complications, the design should be completed by summer with construction beginning in the fall.

The 1,600-foot trail extension has been in the works since 2010, when DelDOT proposed redeveloping the former rail line from Federal Street to Lavinia Street into a biking and pedestrian trail. A 700-foot section of trail from Chestnut Street to Federal Street was previously completed by the town.

According to Delaware Department of Natural Resources and Environmental Control documents, the rail line property contained concentrations of polycyclic aromatic hydrocarbons, material commonly associated with coal, ash or slag, associated with the site’s previous use as a railroad line. According to DNREC, railroad tracks were built along this line sometime prior to 1911.

DNREC spokesman Michael Globetti said the plan calls for placing an environmental covenant on the deeds for the site, requiring DNREC notification for certain conditional uses, which includes recreation.

Work has already begun to clear the site in anticipation of construction. The 10-foot-wide, $1 million trail is 80 percent funded by DelDOT. The remaining $200,000, which the town will pay, is being funded by $110,000 in municipal street aid, and a $90,000 grant from Delaware Greenways.

DelDOT has cleared 20 feet on each side, with the intention of leaving a 13-foot buffer between the trail and private property lines. The project will upgrade a former railroad bridge; DelDOT will maintain the bridge while the rest of the trail will be maintained by the town. DelDOT officials have said construction would take three to five months.