Field Support for the National Performance Evaluation Program (NPEP) for EPA Region 8

ARS’ independent audit team provides audit support for the PM_2.5 Performance Evaluation Program (PEP) and National Performance Audit Program (NPAP) for the Rocky Mountain region.

The EPA operates the NPAP in order to independently assess the ability of monitoring agencies to operate National Ambient Air Quality Standards (NAAQS) criteria pollutant gas monitors that are utilized for determining attainment of NAAQS. The NPAP program ensures that imprecision and bias are low enough that criteria pollutant concentrations measured by State and Local Air Monitoring Systems (SLAMS), Tribal networks, the CASTNET program, Special Purpose Monitor (SPM) sites, and NPS sites are representative of ambient concentrations. ARS’ certified auditing team performs this function for Region 8 via through-the-probe (TTP) auditing to evaluate the entire sampling and analysis system. We coordinate directly with the EPA and the regions’ Primary Quality Assurance Organization (PQAOs) to schedule and complete audits using a mobile auditing laboratory.

The PM_2.5 PEP is a quality program that independently evaluates the measurement system bias of the national PM_2.5 monitoring network to help quantify the quality of data collected via SLAMS and Tribal monitoring networks, the National Core (NCore) Network, the Photochemical Assessment Monitoring Station (PAMS) network, and SPM sites that are used to make PM_2.5 NAAQS determinations. ARS’ certified auditing team performs this function for Region 8 via 24-hour sampling events utilizing a collocated FRM sampler. We coordinate directly with the EPA, the regions’ PQAOs and analytical laboratories to complete PEP audits using our mobile auditing laboratory.