OHA Drinking Water Services
Contact Report Details |
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PWS ID: | OR41 00041 | ||
PWS Name: | AMITY, CITY OF | ||
Who Was Contacted and Phone: | Matt Johnson (971) 237-6683 | ||
Contact Date: | 02/03/2016 | ||
Contacted By: | HOFELD, EVAN (REGION 1) | ||
Contact Method/Location: | Office | ||
Assistance Type: | WATER QUALITY ALERT RESPONSE | ||
Reasons: | Lead or Copper Lead/Copper |
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Details: | SUMMARY: Copper AL Exceedances DETAILS: Actions taken to resolve intermittent copper action level exceedances in Sept2008, Dec2011, and Nov2013 are as follows. Alert generated 1/9/09 prompted first response from DWS followed up in a formal LTR dated 2/20/09 requesting City to issue public notice in CCR, complete source L&C & WQP monitoring, and investigate treatment options. 4/27/11 - City was requested to update sampling plan and increase monitoring to 20 sites every 6-mo (City has been on increased monitoring beg. Dec2011 ever since). 1/11/31 LTR requested City to submit corrosion control plan. On 5/30/12 DWS received a plan for a stepwise approach to raise the pH to 7.8 and then 8.3 using soda ash and then, if copper exceedances persist, the installation of zinc phosphate. Conditional Approval was granted for corrosion control under plan review #87-2012. City was adding soda ash seasonally pre-filtration at the time of the 2014 survey for which the survey letter dated 5/7/14 directed the City to submit a design for zinc phosphate if the City decided to discontinue soda ash. City has had trouble stabilizing pH due to interferences with treatment when injected pre-filtration (later switched to after filtration and pre-clearwell) and, more recently, due to differing source water pH when switching between drawing water through the perforated pipes below the river bed of the S. Yamhill R. to drawing water using a submersible pump resting on the bed of the S. Yamhill R., especially with storms. ACTION NEEDED: Resolve soda ash treatment to obtain stable pH or pursue orthophosphate according to Keller and Assoc. plan, submitted on behalf of the City. City to continue on 6-mo tap sampling & issue Tier 3 notice until treatment is working, two 6-month demo rounds are below the action level for both lead and copper, and minimum water quality parameters have been set by DWS. | ||
Associated Alerts: | CHEM6122 - 12/30/2013 - COPPER SUMMARY |