OHA Drinking Water Services
Contact Report Details |
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| PWS ID: | OR41 00359 | ||
| PWS Name: | CORBETT WATER DISTRICT | ||
| Who Was Contacted and Phone: | Jim Jans (503) 695-2284 | ||
| Contact Date: | 09/20/2013 | ||
| Contacted By: | NUSRALA, JAMES (REGION 1) | ||
| Contact Method/Location: | |||
| Assistance Type: | OTHER REGULATORY - REGULATORY ASSISTANCE | ||
| Reasons: | Operations SWTR |
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| Details: | SUMMARY: Change to calcium hypochlorite and low chlorine readings after clearwell DETAILS: Jim and I spoke on 9/11 and on 9/20 to discuss the Districts recent change from sodium hypochlorite to Accutab 70 % calcium hypochlorite tablets in August 2013, and a corresponding reading of 0.12 mg/L chlorine residual after the clearwell on 8/13. Jim indicated the Accutab system was having trouble deliverying a consistent amount of the chemical which triggered the alarm due to the low chlorine on 8/13. System was fixed and chlorine residual increased to above 0.2 on 8/14. Jim was concerned if he should indicate on Augusts CT form that 1st user residuals did not meet a minimum 0.2 mg/L every day. I clarified that the minimum chlorine residual of 0.2 mg/L applies after the reservoir (which were always > 0.2), at the first user, and that low levels after clearwell and prior to first user are not considered in that evaluation. I also verified NSF Standard 60 certification for Accutab and requested Jim notify DWS prior to major modifications at plant in future ACTION NEEDED: Jim will continue to work with vendor to ensure consistent chlorine dose and notify DWS if the District makes future changes to chlorine residual practices. | ||