A California construction company has to pay at least $725,000 for illegal dumping of waste in a Ventura County, Calif., creek.

T. A. Staben Inc. of Moorpark, Calif., was ordered by the U.S. Environmental Protection Agency (EPA) to pay a $225,000 penalty for dumping imported material into the creek, and at least $500,000 on restoration and mitigation projects, the EPA said in a news release.

The agency said Staben filled Calleguas Creek with 40,000 cubic yards of material, or the equivalent of about 2,000 large dump truck loads. As part of the restoration, Staben will remove the fill and restore the creek’s natural functions.

Between 2005 and 2006, Staben filled approximately five acres of Calleguas Creek, also known as Arroyo Las Posas, without the necessary Clean Water Act permit. The illegal fill substantially reduced the active floodplain in that portion of the creek, increasing potential flooding of adjacent properties and contributing to the bioaccumulation problems that could harm the health of endangered species and other wildlife in Mugu Lagoon, for which the creek is the main source, the EPA said.

Staben, which has a history of noncompliance dating back to 1989, was cited by the Army Corps of Engineers on various occasions for unpermitted work in Calleguas Creek and the Ventura River.