In the late afternoon of 20 February 2015, EPA Region 10 began receiving complaints from the public regarding a noxious odor in the air in the area around LaConner, Washington. Upon coordinating with the Washington Department of Ecology (Ecology), Skagit County Emergency Management, and Swinomish Tribal Police, it was discovered that Shell Refinery in Anacortes, WA, was responsible for the odor release. By the late evening of 20 February 2015, after receiving additional information of the release and concerns from the Swinomish Tribe regarding the length of time of the odor lingering in their area, ER Chief Terada and OSC Boykin deployed to meet with Shell Refinery officials regarding the nature of the release. ER Chief Terada and OSC Boykin confirmed through discussions with Shell that a scrubber unit connected to the East flare was being decontaminated, as part of routine maintenance, when the release occurred. Weather conditions in the area may have exacerbated the release and caused some areas to be more affected by the odor than others, in particular the Shelter Bay and Swinomish Village areas. According to Shell, air monitoring results around the community during the time of the odor complaints were found to be below thresholds that could impact public health. Upon conclusion of the briefing with Shell personnel, ER Chief Terada and OSC Boykin drove around Marchs Point (area of the Shell and Tesoro Refineries), City of LaConner, Shelter Bay, and Swinomish Village to confirm air quality levels.