Regional Haze Planning Work Group

Haze Event, Strawberry Mountain Class I Wilderness Area, Oregon Station Fire, Sunset, California Mount Rushmore National Memorial, South Dakota Sycamore Canyon Class I Wilderness Area, Arizona Sioux Falls, South Dakota
Regional Haze Planning Work Group


The purpose of the WRAP Regional Haze Planning Work Group (RHPWG) is to prepare the framework to support regional planning for the 15 western states, so that needed elements will be available for RH SIP submissions in a timely fashion, to meet the July 2021 deadline for the second planning period of the federal Regional Haze Rule for visibility protection at 118 Class I areas in the 15 western states.

The RHPWG is forming several topical subcommittees from among its members to coordinate and track work by other WRAP Work Groups and contractors.
  • Inventories: current and future (growth projections methodologies by source categories)
  • Develop a transparent and complete monitoring data metric for planning and model projection purposes
  • Database management (including the TSS database)
  • 4-factor analysis
  • Regional photochemical modeling
  • Assessment of “unknowns” and uncertain categories (natural conditions, international emissions, fire and dust emission, et cetera)
  • Development of Regional Haze SIP package content and progress report template
  • Develop control strategies menu for major western state sources

Regional Haze Planning Work Group

2018 Calls and Meetings

April 4, 2018 RHPWG call recording (MP4 format)

2017 Calls and Meetings

June 29th

IMPROVE data and interpretation for Regional Haze planning July 27th

Glide Path and Natural Conditions Teach-In #2 recording (MP4 format) August 31st

Emissions (categories and forecasting) Teach-In #3 recording (MP4 format) October 19th

Modeling Teach-In #4 recording (MP4 format) November 16th

Source Apportionment & Source Control Evaluation (4-factor) Teach-In #5 recording (MP4 format) December 5-7, 2017

Western and National Regional Haze Planning Workshop, Denver (final interactive agenda)
  • December 5 recording (MP4)
  • December 6 recording (MP4)
  • December 7 recording (MP4)