EPA uses the information available, including community input, regarding the boundaries and geographic areas of waste that may have been deposited or where contaminated soil may have been placed. The team selects its soil sampling locations based on those areas and consults historic aerial images that help depict those boundaries.
For a site investigation, there are specific criteria under the Hazard Ranking System (HRS) that dictates what media in the natural environment need to be sampled in order to establish a potential exposure to human health and the environment. For Norwood, the media include surface soils, surface water and sediments. EPA will also evaluate groundwater as a potential pathway of exposure. The groundwater is not being consumed for drinking water in Norwood, as residents are connected to the public water supply; however, the groundwater sampling will help to determine if there is potential for contaminants in groundwater to impact indoor air.