Read the full article by Lauren Ellenbecker (The Columbian)
“The city of Vancouver’s latest sampling results show that ‘forever chemicals’ have lessened in its drinking water — though officials are unsure why.”
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“Samplings from late November show Water Station 14, one of nine water stations in the city, contained PFAS concentrations exceeding Washington’s action levels for perfluorooctanoic acid and perfluorooctane sulfonic acid, two of 29 monitored substances. The chemicals are measured in parts per trillion — one part being a single drop in 20 Olympic-sized swimming pools worth of water.
Washington’s action levels have a threshold of 10 parts per trillion for PFOA and 15 parts per trillion for PFOS. Vancouver’s Water Station 14 measured 11½ parts per trillion for PFOA and 18.6 parts per trillion for PFOS. The results indicate a slight drop from previous samplings, and the reason why is hazy.
‘There’s no clear explanation,’ said Tyler Clary, Vancouver water engineering program manager. However, he has some theories.
Water managers currently adjust operations to prioritize stations with lower PFAS levels while diluting stations with higher concentrations. Water demand typically lessens during colder months, which may also contribute to the lower sample results, Clary said.” …