In May 2010, the US Environmental Protection Agency (EPA) responded to a complaint regarding the placement of fill material contaminated with asbestos cement pipe (ACP). The complainant alleged that in 2009, as part of a waterline improvement project for a rural central Idaho community, a contractor (Owyhee Construction) placed excavated soil containing ACP as fill material on a vacant lot in the community.
In June 2010, EPA conducted a removal evaluation of the vacant lot and observed many scattered pieces of suspected ACP laying on the ground surface. The sizes ranged from 2 to 3 inches in length and width to greater than 6 inches in length and 3 to 4 inches in width. All ACP pieces appeared weathered, the edges were crumbled, and potential asbestos fibers were observed at the edges. Three random grab samples of suspected ACP were analyzed using Polarized Light Microscopy (PLM) analysis to determine asbestos form variety and percent concentration. The data showed asbestos concentrations of 8%, 9%, and 9% chrysotile mineral fibers.
EPA entered into an Administrative Order on Consent (AOC) with responsible parties for an interim removal action to be conducted at the property. The AOC required the respondents to control for fugitive dust, construct a temporary fence around the area where asbestos contaminated material was placed as fill, and install appropriate signage on the fencing to discourage trespass. An interim gravel cover and fence with signage were installed in September, 2010
In the fall of 2010, EPA identified another 21 separate properties in and around Orofino where asbestos contaminated fill had also been placed by Owyhee Construction. Collectively, these 22 sites where asbestos contaminated material had been placed are referred to as the "Orofino Asbestos Site." In 2010 and 2011, EPA cleaned up asbestos contaminated material at 20 of those properties. At the Orofino First Baptist Church, which is another property where a large volume of asbestos contaminated fill had been placed, EPA constructed, with the consent of the property owner, a permanent repository for containing and isolating asbestos contaminated material. See Orofino Asbestos Site web site for more information regarding that property and the overall cleanup - epaosc.org/Orofinoasbestossites. This web site provides specific information on the Riverview Construction Asbestos Unit (RCAU) of the Orofino Asbestos Site.
In April 2016, the EPA OSC conducted a follow-up removal site evaluation at the RCAU with START and ERRS contractors, and IDEQ, to thoroughly evaluate the long-term protectiveness of the “interim” cover that was installed by PRPs in 2010. The EPA found that there were exposed ACP containing soils along the slope that forms the northern boundary of the repository, and that the previously placed gravel cover was uneven and less than the design criteria of 4 inches thickness in 10 of 40 test locations. The EPA OSC concluded that additional removal work was necessary at the RCAU to mitigate a potential exposure of the nearby population to asbestos from the Site.
