DEQ, Newfields, Bishop move dirt

INFOIf you drove to the bridge south of Malta and smelled gas, don't worry it wasn't a leak from your car's fuel line.

The site now known as Tulip's and Treasures at the southernmost part of South Central Ave in Malta was once known as Packy's Convenience Store, a local gas station.

The Department of Environmental Quality (DEQ) from Helena worked with Newfields and Bishop Excavation to finish the weeklong project which removed 2900 cubic yards of dirt and near 1400 cubic yards of contaminated soil. The hole was around 27 feet deep.

Last Wednesday, April 19, the PCN caught up with Brandon Kingsbury from the DEQ, who was the project manager for the site. He is a Petroleum Brownfields Coordinator.

"It was a gas station for a few decades and then Tulips and Treasures, a local floral shop bought it," Kingsbury said. "They are receiving Brownfields grant money as well as Petrofund money from the Petroleum Tank Release Compensation Board. With the two pots of money we are able to have Bishop Excavation out here to remove all of the source mass of contaminated soil."

In the previous years the lot was used as a fuel station, there was a gas leak that eventually contaminated the soil and impacted groundwater around the site.

"Our strategy is that once we take out the source mass of soil, then that will start cleaning up the ground water and that will keep the groundwater from impacting those houses across the street," Kingsbury said. "It was slow leaking over time that wasn't detectable. Back when this gas station was in place, they didn't have technology to measure pressure in pipes."

To remove the soil to ground level, the crews carefully measured the site and were able to move dirt in a safe and controlled environment.

"We will dig down to groundwater, which is probably 26-27 feet," Kingsbury said. "And of course we can't dig out this whole area because we slope down to protect the structural integrity of the building and the highway. For every one foot that we dig down, we have to slope it out a foot and a half."

Bishop Excavating not only removed the old soil, but replaced it with clean soil from their repository.

"Other than that little bit of rain, we were slow at the start but we should be over half done by the end of the day," Shane Bishop said on the second day of the project. "Rain never helps dirt unless you're a farmer."

The site was composed of 10 men, a pair of excavators, four haulers, one loader and one skid-steer.

Though the project finished the dirt fill last Monday, Kingsbury and Soil Scientist Wilhelm Welzenbach of Newfields will continue to monitor the site.

"What we will do after we are done digging, is put in wells and we will periodically test the effectiveness of this excavation off into the future and hopefully issue these owners a no further action letter," Kingsbury said.