OHA Drinking Water Services
Contact Report Details |
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PWS ID: | OR41 00199 | ||
PWS Name: | BEAVER WATER DISTRICT | ||
Who Was Contacted: | Troy Trute and Larry Chitwood | ||
Contact Phone: | 503-392-3966 (Email address hidden) | ||
Contact Date: | 11/30/2022 | ||
Contacted By: | HOFELD, EVAN (DWP) | ||
Contact Method/Location: | |||
Assistance Type: | WATER QUALITY ALERT RESPONSE | ||
Reasons: | Disinfection Byproducts |
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Details: | On 11/29/22 an alert was generated for an HAA5 result of 0.0695 mg/l for the sampling completed at 24325 BUNN CR RD (SM #2) on November 15, 2022 for Beaver Water District. On 11/30/22, I e-mailed the results to Larry Chitwood and Troy Trute and explained to them that, although this was not considered an MCL violation they would need to: 1) Begin monitoring at 24325 BUNN CR RD (SM #2) every quarter starting 1/1/23 for at least 4 consecutive quarters, ending 12/31/23. Although the individual result from November 15th was over 0.060 mg/l, because they are on annual sampling, this is not considered an MCL violation requiring public notice. Violations of the MCL will be based on subsequent quarterly monitoring in 2023. 2) Complete an Operational Evaluation Level (OEL) report form and sent a link to our website on how to complete it. Upon review of the DBP results, the predominant species was due to organics rather than source bromide. I spoke to Troy Trute later on 11/30/22 about moving the chlorine injection point to after the filter rather than before. I sent a copy of the survey Oct 2021 survey report, which had identified an alternative chlorine injection and evaluated the contact time to ensure that disinfection was not adversely affected. 12/12/22 update - chlorine injection had been moved the previous week from prior to filtration to a point after the filter effluent turbidimeter and just prior to soda ash injection (a cationic polymer is now the only thing added prior to filtration). 65.6 minutes of contact time at 90 gpm (5,901 gallons of total pipe volume) is achieved in two parallel pipelines located after soda ash injection and prior to entering the distribution system and the first user. 12/15/22 updated - The OEL report was submitted on 12/15/22, which indicated that they had moved their chlorine injection from pre-filtration to post-filtration, thereby reducing the amount of chlorine needed. |
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Associated Alerts: | CHEM10010 - 11/29/2022 - TOTAL HALOACETIC ACIDS (HAA5) |