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Air Emission Measurement Center (EMC)

Proposed Revisions to Method 202

ACTION

  • On August 23, 2017, the U.S. Environmental Protection Agency (EPA) proposed technical revisions and editorial changes to clarify and update the procedures specified in Method 202.
  • Method 202 describes the procedures that stack testers must follow to measure condensable particulate matter (CPM) emissions from stationary sources. It is known as the “dry impinger” method.
  • This proposal does not modify the method significantly. It is in line with steps EPA has taken since 2010 to improve the implementation of the method and promote consistency in the measurement of CPM.
  • EPA is proposing the following revisions to Method 202:          
    • Revisions to the procedures for determining the systematic error of the method, which is used to correct the results of the measurements made using this method;
    • Removes some procedural options to the method to standardize the way method is performed while also eliminating the potential for additional blank contamination;
    • Revise overly prescriptive requirements for the method specific reagents and equipment with more flexible performance based criteria; and
    • Revise the method to correct inconsistent terminology, improve the readability, and to simplify the text to aid in consistent implementation of the method.
  • EPA will accept comment on the proposal for 60 days after publication in the Federal Register.

BACKGROUND

  • In 2010, the EPA revised Method 202 for determining condensable particulate matter (PM) from stationary sources to improve the measurement of fine PM emissions. These revisions increased the precision of Method 202 and reduced potential bias. The revisions improved the consistency in the measurements obtained between source tests performed under different regulatory authorities.
  • In 2014, the EPA issued interim guidance on the treatment of CPM results in the Prevention of Significant Deterioration (PSD) and Nonattainment NSR Permitting Programs. The guidance addressed concerns that the use of source-specific CPM test results obtained with Method 202 could include a positive bias -- resulting in the overestimation of emissions due to the potential for blank contamination associated with the implementation of Method 202. As part of this guidance, the EPA announced plans to issue guidance on best practices for Method 202 implementation and to revise Method 202 as necessary.
  • In 2016, EPA issued the Best Practices Handbook to mitigate the bias concern, which was developed with significant input from stakeholders and trade groups. The proposed technical revisions incorporate the findings from the handbook.

HOW TO COMMENT

  • EPA will accept comment on the proposal for 60 days after publication in the Federal Register. Comments, identified by Docket ID No. EPA-HQ-OAR-2016-0456, may be submitted by one of the following methods:
  • Federal eRulemaking Portal: http://www.regulations.gov. Follow the online instructions for submitting comments.
  • Email: A-and-R-Docket@epa.gov. Include docket ID No. EPA-HQ-OAR-2016-0456 in the subject line of the message.
  • Fax: (202) 566–9744.
  • Mail: Environmental Protection Agency, EPA Docket Center (EPA/DC), Mailcode 28221T, Attention Docket ID EPA-HQ-OAR-2016-0456, 1200 Pennsylvania Avenue, NW., Washington, DC 20460.
  • Hand/Courier Delivery: EPA Docket Center, Room 3334, EPA WJC West Building, 1301 Constitution Avenue, NW., Washington, DC 20004. Such deliveries are only accepted during the Docket’s normal hours of operation, and special arrangements should be made for deliveries of boxed information.

FEDERAL REGISTER

Proposed Revisions to Method 202 - Dry Impinger Method for Determining Condensable Particulate Emissions from Stationary Sources - Preamble and Rule Text 

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