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OHA Drinking Water Services
Contact Report Details |
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| PWS ID: | OR41 00731 | ||
| PWS Name: | SALEM PUBLIC WORKS | ||
| Who Was Contacted: | Lacey Goeres-Priest | ||
| Contact Phone: | 503-361-2224 (Email address hidden) | ||
| Contact Date: | 08/12/2019 | ||
| Contacted By: | BAIRD, GREGG (DWP) | ||
| Contact Method/Location: | Phone | ||
| Assistance Type: | OTHER WATER QUALITY - Total Microcystins detection in entry point sample below health advisory level | ||
| Reasons: | Cyanotoxins |
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| Details: | Lacey notified the department that total microcystins were detected below the health advisory level at the entry point to the distribution system (finished water at Aldersgate) in a sample collected Sunday 8/11/19 that was analyzed by Salem's in-house lab. The level detected was 0.18 ug/L which is below the health advisory level of 0.3 ug/L for vulnerable people. Salem's in-house lab uses a detection limit of 0.15 ug/L which is lower than the detection limit of 0.3 ug/L used by the DEQ lab to analyze regulatory samples. In addition to reanalyzing Sunday's sample as a double-check, Salem will collect their routine daily raw and finished water samples today to be analyzed by their in-house lab, as well as their regulatory raw and finished water samples that get sent to the DEQ lab for analysis. Four samples will also be collected at representative locations out in the distribution system today and tested for microcystins by their in-house lab. In response, Salem is also modifying their treatment to reduce cyanotoxins by increasing the powdered activated carbon dose from 10 mg/L to 20 mg/L, and increasing the free chlorine residual from 3-3.2 ppm up to 3.75 ppm in the chlorine contact segment. Update: Lacey called later in the day to report that the rerun of Sunday's sample came back non-detect for microcystins. Today's entry point sample was also non-detect for microcystins. Update 8/13/19: Lacey reported that all four distribution samples collected yesterday were non-detect for microcystins. | ||