Availability of Reports on Progress Made Toward the National Visibility Goal in Montana and South Dakota

Résumé

Federal regulations require states to develop a long-term strategy for achieving the National goal of preventing any future and remedying any existing manmade visibility impairment in mandatory Class I Federal areas. The long-term strategy must be periodically reviewed, and revised as appropriate, and a report must be provided to the public and the EPA Administrator. Since Montana and South Dakota never adopted long-term strategies, EPA incorporated a federal long-term strategy into their State Implementation Plans (SIPs) which commits EPA to periodically review the strategies and report its findings to the public. EPA has conducted the required reviews and is announcing the availability of the reports. In Montana, visibility data were available for about half of the 12 mandatory Class I Federal areas. There were no clear visibility improvement or degradation trends at any of the areas for which data were available. Although optical data for Glacier National Park showed no trend through 1996, there was an apparent decline in visibility in 1997. Additional data are required to determine if 1997 marks the beginning of a trend or represents an anomaly. In South Dakota, visibility data