DEQ plans for possible Ozone advisories
In the Upper Green River Basin
by Wyoming Department of Environmental Quality
December 22, 2010
Elevated levels of ozone have been observed in previous years during the months of February and March in the Upper Green River Basin, resulting in the Air Quality Division (AQD) of Wyoming’s Department of Environmental Quality (DEQ) issuing ozone advisories.
Ozone is an air pollutant that can cause adverse respiratory health effects especially to children, the elderly and people with existing respiratory conditions. On days when elevated ozone levels are expected, people in these sensitive groups should limit strenuous or extended outdoor activities, especially in the afternoon and evening. More information on ozone and the health effects of ozone are available at the Wyoming Department of Health website, http://www.health.wyo.gov.
In preparation for the winter of 2011 and the possibility of elevated ozone occurring in the Upper Green River Basin, the AQD is again initiating in-house weather forecasting. Forecasting by the AQD’s meteorologists will consist of evaluating whether a strong temperature inversion in conjunction with low winds, snow cover and clear skies is likely to occur. This is the combination of factors which, together with the presence of ozone forming emissions, appear to result in elevated ozone levels.
If it is determined that conditions favorable for the development of ozone are likely to occur, AQD will issue an ozone advisory for the Upper Green River Basin. This information will be conveyed in three ways to the public. Beginning January 3, the main page of the WDEQ’s website, http://deq.state.wy.us, will carry a daily message (updated by noon every day) as to whether an advisory has been issued for the following day. Also, AQD will notify all media outlets in Sublette County when an advisory is being initiated for the next day. Media outlets include Sublette County newspapers, radio stations, and online news sources. Citizens may also call 1-888-WYO-WDEQ (1-888-996-9337) to hear a recorded message (updated by noon every day) regarding ozone advisory status.
In recognition of the presence of local emissions sources contributing to the formation of ozone, AQD requested short-term emission reduction contingency plans from gas industry representatives operating in Sublette County to be implemented in response to ozone advisories. Since 2009, oil and gas companies including those with production, drilling and service operations have volunteered to take long term actions which reduce ozone-forming emissions and short term actions to further reduce emissions in response to any AQD ozone advisory.
The AQD operates several monitoring stations in the Upper Green River Basin. Real-time monitored data, including current ozone levels being measured at these stations, can be found at www.wyvisnet.com.
This winter, AQD will continue to monitor winter ozone formation in the UGRB through the Upper Green Winter Ozone Study (UGWOS) program. Monitoring will take place Jan. 15 through March 30, 2011. This year’s study will focus on understanding the vertical structure of pollutants in the atmosphere when meteorological conditions are conducive to forming ozone.