The Lapwai School District performs maintenance and repair of school buses and equipment at the Bus Transportation and Maintenance facility. The facility contains a building with two bus repair/equipment bays and an office.
In June 2012, the EPA Region 10 Underground Injection Control (UIC) Program conducted an inspection at the facility. The inspection identified a floor drain in the bus and equipment bay and a drain from a shop sink that reportedly emptied into a nearby drywell located underneath an asphalt parking lot next to the building. In followup to the inspection, the UIC Program required that the school district stop discharging fluids into the drywell, and that the drywell be exposed and sampled. A sample of drywell soils was collected by Nez Perce Tribe Water Resources Division personnel on October 23, 2012. The sample was collected from sludge approximately 18 inches below the surface in the drywell. The drywell itself is made of concrete blocks and is 4’ in diameter and 6’ deep, with the top approximately 4’ below ground surface.
On December 7, 2012 the Nez Perce Tribe provided a report with analytical results from the sample taken in the drywell. The results show elevated concentrations in the well of chlorinated solvents including tetrachloroethylene at 22.5 milligrams/kilogram (mg/Kg), trichloroethylene at168 mg/Kg, as well as lead at 1,840 mg/Kg. On the same property within approximately 150 feet of the contaminated dry well is one of two public drinking water supply well installed and operated by the Bureau of Indian Affairs (BIA). The BIA wells supply drinking water for approximately 300 people in Lapwai, including the Lapwai Elementary School that is adjacent to the school district bus maintenance facility. The BIA wells were recently sampled for volatile organic compounds (VOC) and semi-volatile organic compounds (SVOC), including the contaminants found in the drywell, in January, 2013. As of that time the BIA wells, including the one closest to the contaminated drywell, did not indicate of any contamination above a level of concern.
On January 16, 2013, EPA Region 10 issued a CERCLA Unilateral Admiistative Order (UAO) requiring the Lapwai School District to remove and properly dispose of contaminated sludge and soils in the drywell, remove the drywell itself and remove contaminated soils adjacent to and below the dry well. The UAO also required cleanup confirmation sampling of the excavation pit sidewalls and bottom. The required work was initiated on February 4, 2013.
