GORHAM – A swift response by two Gorham departments prevented an environmental catastrophe last week when a big rig loaded with thousands of gallons of fuel oil rolled over in Gorham.

A tractor-trailer owned by J.P. Noonan Transportation Inc., which has a terminal on lower Main Street in Gorham, tipped over on the roundabout on South Street (Route 114) on June 11.

Some spilled oil made it into a wetlands area and a trivial amount ran into Strout Brook, but most of the spilled fuel has been recovered. Ann Hemenway, oil and hazardous materials specialist with the Maine Department of Environmental Protection, said on Monday at the scene there’s no evidence that the Stroudwater River, wells at four nearby homes or wildlife have been impacted by the spill.

“Gorham Public Works and Gorham Fire Department can be credited with saving the day,” Hemenway said. “The response averted catastrophe.”

Town workers rushed to the scene with truckloads of sand to build dikes to impede the flow of oil that threatened the environment. The public works crew and Gorham firefighters shoveled sand by hand to shore up containment of the spill.

“There were shovels going everywhere,” Gorham Fire Chief Robert Lefebvre said on Tuesday. “It was all hands on deck.”

Lefebvre also said the timing of the incident, which came during a workday afternoon, played a role in the response time.

“Timing was right,” Lefebvre said.

Firefighters from several communities responded to the incident. Oil spilled onto the roundabout pavement was blanketed with Class B foam to eliminate the potential of it igniting.

The drama unfolded when the tractor-trailer landed on its side in mid-afternoon in the Gorham roundabout where South Street and the Bernard P. Rines Bypass intersect. Gorham Police Chief Ronald Shepard said on Tuesday that the cause of the rollover remains under investigation, and he believes a car was involved.

Scarborough Fire Chief Mike Thurlow said at the scene last week that the trailer was loaded with 9,500 gallons, including 3,000 gallons of K1 kerosene and 6,500 gallons of diesel fuel.

“When I got here, it was pouring out of that thing,” Lt. Christopher Sanborn of Gorham Police Department said.

A crew from Clean Harbors Environmental Services in South Portland responded to the scene and continued cleanup this week.

“J.P. Noonan has been fantastic,” Hemenway said about the trucking firm’s cooperation.

Hemenway said that 8,845 gallons spilled from the trailer.

“We’ve recovered at least 7,500,” she said, and more oil was soaked up in absorbent pads and some of the oil evaporated.

The smell of oil lingered at the scene early this week. “We’re looking at a couple hundred gallons on the loose,” Hemenway said on Tuesday.

She was at the scene on Wednesday morning and said by telephone that Shaw Brothers Construction Inc. of Gorham, which built the roundabout, had begun excavating the site where the rollover occurred.

In previous efforts to capture oil from the spill, two dams were built with one on each side of South Street.

Hemenway described them as underflow dams, which allow oil on the water surface to be recovered while water below can flow through PVC pipes extending over the dam.

Hemenway said 2,500 gallons of fuel oil were recovered at the dam near Washburn Drive, a short distance south of the roundabout. A pond of oil was sucked up with a vacuum truck, Hemenway said.

Hemenway said 4,000 gallons were recovered where the truck rolled over in the roundabout. Bagged absorbent pads soaked with oil sat near the roundabout on Monday,

“There’s a significant amount that evaporated,” Hemenway said.

South Street is the westerly border of the 3,600-acre Narragansett Game Sanctuary, a noted deer habitat, and Maine’s Department of Inland Fisheries and Wildlife has been notified about the spill.

Hemenway said a small amount of oil got into Strout Brook, a tributary of the Stroudwater River. The brook, Hemenway said, has American eels, but there’s no evidence of wildlife harm from the oil spill.

“We didn’t see any waterfowl,” Hemenway said.

Four private home wells near the spill area will be tested for contamination.

“We don’t expect any impact,” Hemenway said.

Gorham and state police are investigating cause of the rollover. Shepard said police believe a car was involved but he said there was no contact between the car and the truck. The car left the scene.

Sanborn cited a witness who said a car had pulled out in front of the tractor-trailer, which had been northbound on South Street, and appeared headed toward the bypass. Sanborn described the car as a dark-colored sedan.

According to police, the tractor-trailer driver and a passenger did not require transportation to a hospital. Shepard said both sustained minor bumps and scrapes.

The incident detoured and snarled evening rush-hour traffic. Traffic was bumper to bumper on McLellan Road as drivers were diverted to alternate routes.

Fire departments that responded to the emergency included Buxton, Scarborough, South Portland and Westbrook, in addition to state police and the Cumberland County Sheriff’s Office.

Hemenway did not have any estimated costs associated with response and spill cleanup.

She expected cleanup to wrap up by Thursday this week.

“There will have to be long-term monitoring here,” Hemenway said, at least to fall and possibly into spring.

Firefighting and public works crews were quickly on the scene of an accident last week when a truck loaded with oil rolled over in Gorham. There’s no evidence that the spill impacted local wells or the Stroudwater River.