WALLA WALLA - Monday afternoon, the United States Postal Service (USPS) announced the temporary closure of the Walla Walla main post office located at 128 N. Second Avenue. This closure is just the latest in a string of events that began last week with a report of strong odors of volatile chemicals emanating from the basement of the Marcus Whitman Hotel and Conference Center.

On Thursday, Sept. 14, Walla Walla Fire Department (WWFD) investigators responding to the Marcus Whitman were able to link the odors to a concentration of volatile organic compounds (VOCs), which led to the immediate evacuation and closure of the hotel. Eventually, with help from the Washington State Department of Ecology (DOE), crews discovered pure gasoline in a 10-foot-deep basement sump. The hotel has hired Clean Harbors Environmental Services, a cleanup company, to help mitigate the situation. Efforts have been made to ventilate the affected areas, making it possible to clean and further investigate the source of the gasoline.

Initial suspicions were placed on a 10,000-gallon fuel tank buried beneath the Chevron Station across the street from the hotel on the corner of Rose and 2nd. However, crews have since performed tightness tests on the suspected storage tank which indicate it is not the source of the gasoline leak. Currently, DOE is leading the investigation of the leak, focusing on additional fuel tanks on the Chevron property as well as those under the Circle K station at 315 N. 2nd Ave.

While making air quality checks of the surrounding buildings, WWFD crews discovered an equally dangerous situation in the basement of the vacant building at 106 N. 2nd Ave., next to the Chevron station, including high levels of VOCs and gasoline collecting in a sump. Further tests over the weekend revealed the concentration of VOCs in the basement of the Post Office next door, which led to Monday’s closure decision.

In a statement from the USPS, Walla Walla Post Office Box customers are advised that they will be able to collect their mail at the College Place Post Office, which is located at 500 South College Ave. Outgoing mail collection boxes along Sumach Street on the northern corner of the Walla Walla Post Office have been closed. Other collection boxes in the city remain open, while mail carriers for the city will operate out of the West Richland Post Office.

Pedestrian and street traffic has been closed along N. 2nd Avenue between West Cherry and West Rose Street, as well as Sumach Street between N. Second Avenue and North Colville Street.

The Walla Walla Public Works Department is working closely with the DOE to monitor the city water system and ground waterways for any evidence of gasoline seepage. As of now, none has been detected. Air-quality monitors have also been placed in several areas to alert to increased concentrations of VOCs inside and outside the affected buildings.

The City of Walla Walla is providing detailed updates to this developing situation on their website at https://www.wallawallawa.gov/services/advanced-components/list-detail-pages/news-list