The ETV Programs's AMS Center conducts third-party performance testing of commercially available technologies that monitor, sample, detect, and characterize contaminants or naturally occurring species across all matrices. The purpose of TEV is to provide objective and quality-assured performance data on environmental technologies so that users, developers, and regulators, and consultants can make informed decisions about purchasing and applying these technologies. Stake holder committees of buyers and users of such technologies recommend technology categories, and technologies within those categories, as priorities for testing. The research described in the QAPP is focused on evaluating LD technologies in general to produce a TA that is not specific to a vendor or LD technology category. The purpose of this QAPP is to specify procedures for gathering data to inform the TA and the UST LD community as a whole.