The Ambler Asbestos Piles site is located in the southwestern portion of the Borough of Ambler, Montgomery County, Pennsylvania. Land around the site is used for industrial, residential, commercial, and transportation purposes. The site consists of four distinct areas of asbestos contamination. The waste piles of concern are the Locust Street Pile and the Plant Pile. The K&M Company owned and operated the site from the late 1800s to 1962, and produced asbestos products such as paper, millboard, electrical insulation, linings, conveyor belts, and high pressure packings. The primary wastes generated and disposed of in the Locust Street and Plant Piles during that period were spent magnesium/calcium (from pharmaceutical operations) and asbestos process waste. In 1962, CertainTeed Corporation purchased a portion of the site and facilities from K&M and manufactured asbestos-cement pipe at the plant. EPA and the Pennsylvania Department of Environmental Resources conducted their first investigation of the site in 1971, noting visible emissions and substantial dust concentrations attributed to asbestos. Subsequent investigation of the surface water, bulk waste samples and air samples in 1983 revealed asbestos contamination. The selected remedial action for this site is given.