Why is soil gas monitored at landfills?
There are many reasons for monitoring levels of contaminants in soil gas at or near landfills. The three main reasons that such monitoring is performed are reviewed below, though soil gas monitoring might be conducted for other reasons. Information about sampling methods and the relevance of the monitoring results to public health is presented later in this chapter. • To meet regulatory requirements. According to EPA regulations under RCRA (Subtitle D), MSW landfills must conduct soil gas monitoring for methane. Depending on the date of construction, some MSW landfills may be exempt from these RCRA regulations. EPA regulations provide flexibility for how states and Indian tribes implement these regulations. As a result, landfills operating in some states or tribal areas might be subject to different regulations than landfills operating in other areas. The data collected in fulfillment of these regulations serve two important purposes: they provide environmental regulators with informat
