Air Pollution:

EPA's Actions to Resolve Concerns with the Fine Particulate Monitoring Program

RCED-99-215: Published: Aug 12, 1999. Publicly Released: Aug 27, 1999.

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Pursuant to a congressional request, GAO reviewed the National Academy of Sciences March 1998 report on the Environmental Protection Agency's (EPA) plans to monitor particulate matter smaller than 2.5 microns (PM2.5), focusing on: (1) EPA's actions in response to the Academy's concerns with the planned PM2.5 monitoring program; and (2) the challenges that state and local agencies face in establishing and operating the PM2.5 monitoring program, as well as EPA's response to these challenges.

GAO noted that: (1) EPA has taken a number of actions to address the concerns raised in the Academy's March 1998 report, including allocating 57 percent of its monitoring budget to efforts designed to better understand PM2.5 scientific uncertainties--a primary concern in the Academy's report; (2) although one of the Academy's concerns was that the agency was moving forward rapidly with too narrow a focus on mass-only monitors, EPA continued its rapid deployment of over 800 mass-only monitors by December 31, 1998, on the basis that 3 years of monitoring data were needed to determine attainment with the standards; (3) agency officials also explained that they deployed these monitors in response to presidential and congressional directives to expedite the monitoring network, as well as extensive public comments regarding the thousands of premature deaths and serious illnesses annually from PM2.5 pollution; (4) the officials also said that they deployed these monitors only after the monitors and the network design were peer-reviewed; (5) largely due to EPA's rapid deployment of mass-only monitors, state and local agencies have encountered problems operating nearly one-third of their monitors--problems that have increased labor costs and impacted the agencies' ability to meet EPA's data quality requirements; (6) the officials explained that, due to EPA-imposed time constraints, they had to purchase mass-only monitors based on prototype design and manufacturer specifications without full field evaluation under actual operating conditions; (7) while deployment was rapid, EPA officials said the agency's monitor certification process was followed and that EPA has taken other actions to help states address these challenges, including requesting warranty extensions from the affected manufacturers and increasing funding for operation and maintenance activities; (8) however, state and local agencies remain concerned that the future deployment of the more complex and costly speciation monitors without adequate field testing would present even greater challenges; and (9) as a result, EPA has reevaluated its monitoring plans and delayed deployment of the more complex and costly speciation monitors an additional year--to December 2000--to allow more time for field testing.

Recommendation for Executive Action

  1. Status: Closed - Implemented

    Comments: EPA agrees with the recommendation and has acted to implement it. According to EPA documents, EPA has deployed over 300 chemical speciation monitors throughout the country.

    Recommendation: The Administrator, EPA, should ensure that all remaining monitors planned for the PM2.5 network undergo and successfully pass full laboratory and full field testing and evaluation under actual operating conditions to ensure that the monitors meet data quality objectives before large-scale deployment of these monitors is authorized.

    Agency Affected: Environmental Protection Agency


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