As we previously noted in an earlier post, residents and businesses in the Pierpont area of Ventura, CA, were notified by city officials earlier this week not to use or drink their water due to gasoline contamination.
However, that order has been officially lifted as of Wednesday, November 26, at 12:15 PM. City officials now say the water is safe to drink and that the original order was made due to a false positive for gasoline during routine testing.
Subsequent tests on several additional water samples have shown no such contamination. According to the city, the laboratory doing the testing, Eurofins Calscience, explained the false positives were caused by "carryover from unrelated high-concentration samples tested earlier in the batch. Reanalysis (and analysis of additional new samples) showed no detection of gasoline."
In short, Eurofins Calscience said the contamination of the Pierpont samples was due to contamination from samples from another, unrelated site that were done before the Pierpont samples were analysed. Retesting showed no contamination.
Such an error does raise questions about quality control procedures during the analysis of samples from different sites.
You can see Eurofin Calscience's explanation here: False Positive letter from Eurofin Calscience to Ventura
