Three companies have agreed to pay almost $4 million to restore habitat damage caused by mill and manufacturing operations in Everett that date to the early 20th century.

Weyerhaeuser Corp., Jeld-Wen Inc. and Kimberly Clark Corp. have operated pulp and paper mills, machine shops, casket builders and other endeavors in the Port Gardner Bay area near the mouth of the Snohomish River.

The federal government and Washington state filed a complaint Thursday against them in U.S. District Court in Seattle, on behalf of the Tulalip and Suquamish tribes.

The tribes blame the companies for pollution, including from oil, heavy metals and PCBs, that damaged shellfish beds and other natural resources.

According to a proposed settlement, the companies would pay $3.9 million for habitat restoration projects. The settlement is subject to a monthlong public comment period, however, and the tribes could pull out of the settlement if further environmental damage is revealed during that time.