LIBERTY (AP) — A Texas energy company says it has hauled away about 400 truckloads containing 7,000 tons of contaminated dirt from an oil well blowout site in Amite County.

Dallas-based Denbury Resources Inc. also says its investigation continues into the Dec. 16 blowout that shut down a highway and caused the evacuation of nearby homes.

The Amite County blowout caused carbon dioxide to escape the well. No fire was reported at the scene and officials said the blowout posed no imminent threat to residents. Local officials evacuated nearby homes as a precaution.

Denbury officials said the incident involved a well that was built in the 1970s and later revitalized using carbon dioxide infusion. The pressurized gas is used to loosen oil deposits from previous drilling and force them to the surface.

This past week, officials with the Mississippi Department of Environmental Quality and the U.S. Environmental Protection Agency toured the site with Denbury environmental manager Randy Robichaux.

Robichaux said Denbury has spent an estimated $3 million so far and also may face fines from the EPA.

‘‘It’s not out of the ordinary to receive a fine on any release,’’ Robichaux said.

The dirt was contaminated by crude oil and saltwater over a couple of acres to depths up to around 2 feet, Robichaux said. Denbury sank four groundwater monitoring wells at the site and checks a neighboring well and Northeast Amite County Water Association water.

‘‘We haven’t found anything elevated of any significance at all,’’ Robichaux said.

He said dirt removal should take a couple of more weeks. Then Denbury will spread fertilizer and hay to get grass growing, possibly followed by tree planting.