Air Pollution:
Reliability of EPA's Mobile Source Emission Model Could Be Improved
RCED-90-138: Published: May 14, 1990. Publicly Released: Jun 18, 1990.
Additional Materials:
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Pursuant to a congressional request, GAO examined the: (1) reliability of the Environmental Protection Agency's (EPA) mobile source emission factor model (MOBILE4); and (2) effect of budget constraints on MOBILE4 reliability.
GAO found that: (1) in order to enhance MOBILE4 reliability, EPA needed to define MOBILE4 assumptions; (2) although EPA had not determined the overall reliability of MOBILE4, EPA believed that its statistical reliability should surpass the previous version's; (3) EPA continued to develop and update model assumptions, which should improve the reliability of the next version; (4) MOBILE4 remained an important tool to understanding efforts to limit and decrease air pollution; (5) funding constraints limited EPA ability to perform emission testing of later motor vehicles, so MOBILE4 estimates were less reliable than its projections for earlier model years; (6) EPA addressed funding inadequacies by providing increased funds in fiscal year (FY) 1989 and FY 1990; and (7) EPA funding for MOBILE4 increased from $807,000 in FY 1988 to $1.5 million in FY 1989 and $2.1 million in FY 1990.
Mar 1, 2021
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Man-Made Chemicals and Potential Health Risks:
EPA Has Completed Some Regulatory-Related Actions for PFASGAO-21-37: Published: Jan 27, 2021. Publicly Released: Mar 1, 2021.
Jan 22, 2021
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U.S. Army Corps of Engineers:
Information on the Navigation and Ecosystem Sustainability ProgramGAO-21-240R: Published: Jan 22, 2021. Publicly Released: Jan 22, 2021.
Jan 19, 2021
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Chemical Assessments:
Annual EPA Survey Inconsistent with Leading Practices in Program ManagementGAO-21-156: Published: Dec 18, 2020. Publicly Released: Jan 19, 2021.
Jan 15, 2021
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Environmental Liabilities:
NASA's Reported Financial Liabilities Have Grown, and Several Factors Contribute to Future UncertaintiesGAO-21-205: Published: Jan 15, 2021. Publicly Released: Jan 15, 2021.
Jan 13, 2021
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Nuclear Waste:
Congressional Action Needed to Clarify a Disposal Option at West Valley Site in New YorkGAO-21-115: Published: Jan 13, 2021. Publicly Released: Jan 13, 2021.
Jan 7, 2021
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Hanford Cleanup:
DOE's Efforts to Close Tank Farms Would Benefit from Clearer Legal Authorities and CommunicationGAO-21-73: Published: Jan 7, 2021. Publicly Released: Jan 7, 2021.
Dec 18, 2020
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Drinking Water:
EPA Could Use Available Data to Better Identify Neighborhoods at Risk of Lead ExposureGAO-21-78: Published: Dec 18, 2020. Publicly Released: Dec 18, 2020. -
Recycling:
Building on Existing Federal Efforts Could Help Address Cross-Cutting ChallengesGAO-21-87: Published: Dec 18, 2020. Publicly Released: Dec 18, 2020.
Dec 9, 2020
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Environmental Protection:
Action Needed to Ensure EPA's Enforcement and Compliance Activities Support Its Strategic GoalsGAO-21-82: Published: Dec 9, 2020. Publicly Released: Dec 9, 2020. -
Oil and Gas:
Onshore Competitive and Noncompetitive Lease RevenuesGAO-21-138: Published: Nov 19, 2020. Publicly Released: Dec 9, 2020.
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