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HomeMy WebLinkAbout16 Water Supply Permit Agenda Item # 16 F Public Utility Distri.-.- WORKSHOP To: Board of Directors From: Mark Thomas Date: February 17, 2010 Subject: Review the Status of Water Supply Permit 1. WHY THIS MATTER IS BEFORE THE BOARD The Board asked for a review on the status of the water supply permit for Glenshire Drive Well. 2. HISTORY On December 3, 2008, the Glenshire Drive Well was sampled for arsenic as part of normal water quality sampling. The results for this arsenic sample came back at 13ppb which was over the State of California Department of Public Health (CDPH) maximum contaminant level (MCL) of 10ppb. Staff then notified CDPH of the arsenic result over the MCL. On February 18, 2009, the District received written notice of increased monitoring for arsenic at Glenshire Drive Well. This notice increased the monitoring for arsenic at Glenshire Drive Well from once every three years to one sample per calendar quarter, starting with the first calendar quarter of 2009, for the next nine months. The results of the quarterly testing were 12.1 ppb which ended in September of 2009. On October 21, 2009, staff reported the CDPH compliance order issue for the Glenshire Drive Well to the Board. As part of the compliance order, the District was required to send out a public notification for the arsenic MCL exceedance to all the District's water customers. This notice was mailed out on October 30, 2009, and then published in the Sierra Sun on November 11, 2009. 3. NEW INFORMATION On October 26, 2009, staff began blending testing of Glenshire Drive Well with Prosser Village Well and Old Greenwood Well. The blending testing was then completed on November 25, 2009. The test results showed that the best rate of flow is 1,500gpm from the Glenshire Drive Well with Prosser Village Well at 850gpm and Old Greenwood Well at 900gpm. At these flow rates, the arsenic at the blending sample points is 7ppb. Staff also ran a blending test with Glenshire Drive Well at 1,200gpm with only Prosser Village Well on at 860gpm and Old Greenwood Well off. The results were again 7ppb. From these results, staff began the water supply permit amendment process for the District's Main System. The permit amendment is to allow the blending of Glenshire Drive Well at two different flow rates; one at 1,500gpm and the other at 1,200gpm. The 1,500gpm flow rate requires that both Prosser Village Well and Old Greenwood Well be running at the same time with Glenshire Drive Well. The 1,200gpm flow rate requires that either Prosser Village Well or Old Greenwood Well be running at the same time with Glenshire Drive Well. Also as part of the permit amendment, staff is required to sample for arsenic each month at the blending point, and at the 3 wells; and to provide a written report to the CDPH each month that blending is taking place. On December 15, 2009, staff went to Redding to meet with the CDPH District's Engineer Richard Hinrichs and Associate Sanitary Engineer Gary Schultz. As a result of the meeting, verbal approval was received for the proposed water supply permit amendment, and lifted the compliance order for Glenshire Drive well. On February 9, 2010 the District received the written approval from the CDPH (Attachment 1). 4. FISCAL IMPACT There is no direct fiscal impact associated with this workshop item. 5. RECOMMENDATION Receive and comment on this report. _ Michael D. Holley General Manager/ Water Utility Manager STATE OF CALIFORNIA AMENDMENT TO THE DOMESTIC WATER SUPPLY PERMIT ISSUED TO Truckee Donner Public Utility District (TDPUD Main-Public Water System No.2910003) ORIGINAL WATER PERMIT NO. 82-015 DATE OF ISSUE: March 5, 1982 PERMIT AMENDMENT NO. 01-21-10(P)82015A1 EFFECTIVE DATE: February 9,2010 WHEREAS: 1. The Truckee Donner Public Utility District (TDPUD) submitted an application to the State of California Department of Public Health (CDPH), dated December 7, 2009, for an amendment to the Domestic Water Supply Permit issued to the Truckee Donner Public Utility District for the Main Water System on March 5, 1982. 2. The purpose of the amendment, as stated in the application, is to allow the TDPUD Main Water System to use the Glenshire Drive Well that produces water that exceeds the current USEPA and State of California Maximum Contaminant Level (MCL) for arsenic (running annual average cannot exceed 10 parts per billion). TDPUD has documented that operation plan measures can be implemented in the public water system to ensure that the water pumped from the Glenshire Drive Well will at all times be blended with other well water, and that the blended water delivered to all customers served by the distribution system will meet the arsenic MCL. The blending operation is considered to be a form of treatment. TDPUD must follow an approved blending operations plan that will document the measures to be implemented when the Glenshire Drive Well is used. The Glenshire Drive Well Blending Operations Plan on file with CDPH currently specifies that the following measures will be implemented for the use of the Glenshire Drive Well: a. Fairway Drive Valve 1 and Glenshire Drive Valve 1 will be closed (as shown on Attachment 4 of permit amendment application), b. SCADA system protocol will be programmed for the Prosser Village Well and the Old Greenwood Well to be lead wells and the Glenshire Drive Well to be the third well (lag) behind the other two wells, c. A throttling valve will be installed in the Glenshire Drive Well discharge piping to lower the flow from 1,800 gallons per minute(gpm)to 1,500 or 1,200 gpm, d. Well water will mix at the mixing cross(Attachment 4 of permit amendment application) and arsenic compliance samples will be taken at the mixing cross East Sampling Point and the West Sampling Point. 3. TDPUD has submitted all of the supporting information required to evaluate the Glenshire Drive Well blending operation permit amendment application. Truckee Donner Public Utility District-Main Water System PWS No. 2910003 Permit Amendment 01-21-10(P)82015 A 1 February 9, 2010 Page 2 of 2 4. The CDPH has evaluated the permit amendment application and the supporting documentation and has determined that TDPUD may use the Glenshire Drive Well on a routine basis,but only subject to TDPUD following a CDPH approved blending operations plan (referred to as the Glenshire Drive Well Blending Operations Plan). TDPUD has documented that a blending operation can successfully blend water from the Glenshire Drive Well with other wells to deliver a blended water to the distribution system that will comply with all applicable State drinking water requirements and the arsenic MCL. 5. As responsible agency, the CDPH has considered the Worksheet for CEQA Exemptions prepared by TDPUD. The CDPH hereby makes the following findings for the permit amendment: a) The project will not result in any significant impacts. b) There are no recommended CEQA permit conditions. THEREFORE: 1. The Domestic Water Supply Permit issued to the Truckee Donner Public Utility District for the Main Water System on March 5, 1982,is hereby amended as follows: TDPUD may use the Glenshire Drive Well on a routine basis for a source of supply, but only in conjunction with TDPUD implementing measures in a CDPH approved Glenshire Drive Well Blending Operations Plan that establishes the blending operation that is to be followed to meet the arsenic MCL. 2. This permit amendment is subject to the following special conditions: a) TDPUD shall comply with the CDPH approved Glenshire Drive Well Blending Operations Plan (Plan) when operating the Glenshire Drive Well under normal operating conditions. TDPUD may deviate from the Plan without CDPH approval when using the Glenshire Drive Well under emergency conditions,but shall notify CDPH within 24 hours of the Plan deviation. This permit amendment shall be appended to and shall be considered to be an integral part of the Domestic Water Supply Permit issued to the Truckee Donner Public Utility District for the Main Water System on March 5, 1982. FOR THE CALIFORNIA DEPARTMENT OF PUBLIC HEALTH Date Richard L.Hinrichs,P.E. Valley District Engineer Drinking Water Field Operations Branch