Lab analyzing samples from Walla Walla gasoline storage tanks

News release from city of Walla Walla

WALLA WALLA – On Thursday, Sept. 21, 2023, Walla Walla Fire Department personnel delivered samples from each of the gasoline storage tanks at the Chevron and Circle K stations to a lab in Portland for forensic “fingerprint analysis.” Leak testing of the gasoline lines and storage tanks at both stations is tentatively scheduled for Tuesday, Sept. 26.

Two more wells were put in on Thursday and more hole drilling and well placement is planned for the weekend. Samples will be collected by Department of Ecology staff and sent off for testing, which will help the investigation team track down the source of the gasoline.

A subcontractor, GeoEngineers, has taken on the drilling operations for the wells and for sub-slab vapor testing. In the sub-slab testing, 3/4″ holes are drilled through the sidewalk slab to allow for the use of photoionization detectors (PIDs), which detect and measure volatile organic compounds present.

Clean Harbors crews continue their ventilation and pumping operations at the Marcus Whitman Hotel and 106 N. 2nd Ave. The situation at these buildings continues to be stable.

Environmental Protection Agency personnel continue to be on site to provide technical advice regarding groundwater and Mill Creek. There continues to be no evidence of gasoline contamination entering Walla Walla’s waterways.

WWFD continues to perform regular air quality monitoring at buildings around the area, with no changes detected.

The response team appreciates the flexibility of the community as we learn more about the situation and adjust our approach to changing conditions.

City staff will continue to provide these updates on the City website (https://www.wallawallawa.gov/gasoline) as the situation changes.

Photo shows Clean Harbors and the Washington State Department of Ecology inspecting a stormwater utility access on 2nd Avenue on Thursday.

---

Elkhorn Media Group

---

---