A federal environmental agency has ordered the owner of two hardware stores on Hawaii island to shut down four illegal large cesspools.

The U.S. Environmental Protection Agency has announced Maui Varieties Investments, Inc. will close large capacity cesspools at the Naalehu and Kamuela HouseMart Ace Hardware stores and at a Hilo commercial property where a farm supply store is located. The company also has been ordered to pay a $134,000 fine.

The agency found three large cesspools at the Naalehu and Kamuela sites during inspections conducted in 2016. The owner informed inspectors of a fourth cesspool at the Hilo property.

Maui Varieties Investments is slated to replace two cesspools that serve the Naalehu store with a wastewater treatment system approved by the state health department. The Kamuela store will be connected to a private sewer system and the Hilo commercial property will be connected to the county’s sewer system.

Large capacity cesspools that serve multiple residential dwellings or a commercial facility have been banned since April 2005 under the federal Safe Drinking Water Act. The cesspools discharge waterborne pollutants like untreated raw sewage into the ground where harmful bacteria can contaminate groundwater, streams and the ocean.

The federal agency said cesspools are “used more widely used in Hawaii than in any other state.”