The tie treatment plant has been operating in The Dalles since 1922. DEQ issued the first air quality permit for the plant in 1977. Kerr-McGee Corp. operated the plant from 1987 through 2004. Amenities West LLC is the current owner.
When Kerr-McGee took over the operations in 1987, it made several improvements at the plant that reduced emissions and the number of complaints decreased dramatically. However, during the permit renewal process in 2002, DEQ received numerous comments about odors and other issues. The permit was issued as proposed, but DEQ committed to work with the concerned residents and Kerr-McGee to try and resolve the issues.
A workgroup was formed consisting of concerned residents, DEQ staff, and plant personnel, and met for the first time in July 2002. Many concerns were brought to the table and discussed at the first meeting. Due to limited resources, many of the things people wanted done (including a health effects study, ambient monitoring program, immediate installation of capture and control systems, etc.) were beyond the scope of the workgroup. The workgroup decided to concentrate on collecting information that would be useful to the plant for identifying the root cause of the odors. With this information, the plant could possibly make changes to their operations or identify areas that need additional control to abate the odors. To this end, the workgroup agreed to coordinate a series of odor surveys.
The workgroup conducted a series of informal odor surveys between Nov. 2002 and Aug. 2004 to gather information about the frequency and strength of the odors. The surveys were initially mailed or delivered to those that attended the public hearing and those that lived near the plant. The surveys were also announced in the local paper. Those who participated in the surveys recorded several odor events ranging from mild to extremely unpleasant. An attempt was made to correlate the odor events with plant activities, but there was no consistent pattern. It appeared that the odor events were more likely to occur based on the weather conditions. In general, most of the odor events occurred on warm days when there was a light breeze.
The previous owner formed a Quality Action Team to evaluate odor causing activities and make recommendations for improvements to reduce odors. Several improvements were implemented that may have reduced odors. An odor questionnaire was mailed to all residences in The Dalles in early Sept. 2005 and DEQ held a public meeting on Sept. 14, 2005. Of the 8,757 surveys mailed, DEQ received 724 and 288 of the respondents clearly identified the tie treatment plant as a source of odors.
DEQ continues working with residents and the tie treatment plant to reduce odors and emissions coming from the facility.