OHA Drinking Water Services
Contact Report Details |
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PWS ID: | OR41 00055 | ||
PWS Name: | ASTORIA, CITY OF | ||
Who Was Contacted and Phone: | Gary McLauchlin (503) 325-3524 | ||
Contact Date: | 12/29/2009 | ||
Contacted By: | HOFELD, EVAN (REGION 1) | ||
Contact Method/Location: | Office | ||
Assistance Type: | WATER QUALITY ALERT RESPONSE | ||
Reasons: | Disinfection Byproducts DBPs |
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Details: | SUMMARY: Single result above the HAA5 MCL DETAILS: Gary McLauchlin called to verify if they needed to issue a public notice or take further action after a DBP sample taken 12/10/09 resulted in a single result of 0.1039 mg/l for HAA5, above the MCL of 0.060 mg/l. I told him that since the MCL is calculated based upon a running annual average, no further action was needed at this time, other than to report the result in the 2009 CCR. I asked if he knew what may have caused the high result and he theorized that it may have been due to tannins in the source water, due to a noticeable drop in pH and a need to increase the chlorine dose to maintain the same residual. ACTION NEEDED: Report the result in the 2009 CCR. No further action needed at this time. System is in the process of covering open reservoirs, which is thought will help mitigate DBP formation in addtion to meeting LT2 requirements. | ||
Associated Alerts: | CHEM3871 - 12/18/2009 - TOTAL HALOACETIC ACIDS (HAA5) |