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Visibility and Haze

Regional Haze Guidance Technical Support Document and Data File

Section 5 of the Draft Guidance on Progress Tracking Metrics, Long-term Strategies, Reasonable Progress Goals and Other Requirements for Regional Haze State Implementation Plans for the Second Implementation Period includes references to a Technical Support Document (TSD) and a data file containing results for each IMPROVE monitor. This page contains these supporting documents and files, including an updated version of the data file.

  • RH TSD - Data File (XLSX)(1 pg, 16 MB)  This is the original data file posted along with the draft guidance document.
  • RH TSD - thru 2015 (ZIP)(1 pg, 23 MB)  This is an updated and revised version of the above data file. This data file includes values for all days of the year, includes 2015 IMPROVE data, corrects a small technical error that affected a small number of Class I areas, combines data for sites in close proximity where sampling has moved to a nearby location (labeled as the new site), and for a few Class I areas uses a different (or additional) IMPROVE monitoring site to represent the areas. The posting of this data file does not indicate that EPA has completed its review of the public comments on the draft guidance document or decided to finalize the recommendations in the draft document.
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