Quality assurance and quality control are required for all water quality monitoring programs using EPA funding, but should be followed for all monitoring programs. BY law, any EPA funded monitoring project must have an EPA-approved QAPP (see below) before it can begin collecting samples. Water Quality agencies will not use monitoring data unless the methods of data collection, storage, and analysis can be well documented.
Quality Assurance (QA) is the overall project management system and includes the organization, planning, data collection, quality control, documentation, evaluation, and reporting or the monitoring activities. QA provides the information needed to 1) determine the quality of the data and whether they meet the requirements of the project and 2) ensure that the data will meet defined standards of quality with a stated level of confidence.
Quality Control (QC) refers to the routine technical activities whose purpose is, essentially, error control. Because errors can occur in either the field, the laboratory or in the office, QC must be a part of each of these functions.
Quality Assurance Project Plan (QAPP) is the written record of your QA/QC program. A QAPP documents the planning, implementation, and assessment procedures for a particular monitoring project, as well as any specific QA or QC activities. It integrates all the technical and quality aspects of the project in order to provide a “blueprint” for obtaining the type and quality of environmental data and information needed for a specific decision or use.