OHA Drinking Water Services
OHA Drinking Water Services
Contact Report Details

PWS ID: OR41 01479
PWS Name: TWILIGHT VIEW ESTATES
 
Who Was Contacted: Reggie Boltz
Contact Phone: 541-218-5555
Contact Date: 02/05/2021
Contacted By: CIVIL WEST ENGINEERS, INC (DWP)
Contact Method/Location: Phone
 
Assistance Type: CIRCUIT RIDER ASSISTANCE
 
Details: Background/Problem Identification:
Twilight View Estates water system was tested for copper content and exceeded the copper action level (AL) of 1.3 mg/L. The results were first received by the state on May 3rd, 2002 and subsequently on October 8th, 2010 and September 1st, 2016. Notice of exceeding the AL was sent to the water system on February 1st, 2018. Part of the requirement of this notice was that the water system needed to receive a recommendation from a water system engineer for an optimal corrosion control treatment.

Assistance Provided:
Based on the EPA OCCT, and the source water quality parameters, we recommend adding caustic soda to increase the pH to 7.5 and to add an orthophosphate product.

https://www.epa.gov/sites/production/files/2016-03/documents/occtmarch2016.pdf
We recommend injection of the caustic soda immediately downstream of the pressure tanks with chemical metering pump. The same pump that TVE has purchased to inject the orthophosphate (LMI PD041-828SI) may also be employed for the caustic soda injection. We recommend using 25% liquid caustic soda to both avoid freezing issues, and to limit operator exposure. The operator MUST read and follow all SDS recommendations for caustic soda. To push the raw water pH of 6.5 to the target pH of 7.5, the operator should slowly adjust feed quantity from the pumpís minimum setting until a pH of 7.5 is reached. This may take some time to establish. We recommend making changes of no more than 5% and waiting a day or two to test for the resultant pH in distribution.

Follow-Up Actions Needed:
The circuit rider is available as needed for follow-up assistance.

Technical Reports to be Prepared and Expected Timeframe:
This technical assistance contact report was sent out on February 5th, 2021.



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System Info :: Report for Lenders :: Alerts :: Violations :: Compliance & Enforcement :: Contacts & Advisories :: Site Visits :: Public Notice
Coliform Summary :: Coliform Results :: Sampling Schedule for Coliform :: Groundwater/GWUDI Source Details :: Plan Review :: Annual Fee
Chemical Group Summary :: Latest Chemical Results :: Entry Point Detects :: Single Analyte Results 
Chemical Schedule Summary :: Chemical Schedule Details
Lead & Copper :: Corrosion Control (LCR) :: Nitrate :: Arsenic :: Radionuclides :: GWR 4-Log :: LT2 :: Cyanotoxins :: PFAS
DBPs :: TOC & Alkalinity :: DBP Sample Sites :: FANLs :: MRDL :: Turbidity :: SWTR :: RAA :: LRAA For SDWIS: 4399