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Release of natural gas odorant part of South Plant valve work, Sept. 10


Five projects that will help improve air and water quality in the Duwamish Basin earned $102,875 in funding through King County Wastewater Treatment Division’s Green Grants program.


An odorant that helps people identify natural gas leaks will be released briefly during a valve replacement project on the gas scrubbing system at King County’s South Treatment Plant in Renton.

The work is scheduled for Tuesday, Sept. 10 at 8 a.m., and is expected to take about 20 minutes. There will not be an actual release of natural gas.

Representatives from Puget Sound Energy will be onsite with a carbon truck to capture the released mercaptan, which is the odorant added to natural gas as a safety measure. The nearby community is unlikely to experience nuisance odor associated with the project.    

King County notified the Renton Fire Department about the project.  

Since the early 1980s, King County has captured the biogas created as natural byproduct of the treatment process. South Plant’s gas scrubbing system removes carbon dioxide and other impurities, creating natural gas that is used onsite or sold to Puget Sound Energy.

Additional information about the Wastewater Treatment Division’s resource recovery efforts is available on the website.