The OSL water system does not have adequate source of treatment capacity. In addition, the distribution system is unable to adequately distribute treated water and meet summer water demands. To prevent water outages, Hillview utilizes two sources that do not meet the primary drinking water standard for uranium. One of the two wells is treated; however, the existing treatment system cannot effectively remove the uranium to meet the drinking water standard. The distribution system does not have enough hydraulic capacity to efficiently distribute the treated water. Hillview has implemented mandatory water conservation measures.
The OSL System lacks adequate production, treatment, and distribution capacity, which have produced severe water shortages and the failure to meet certain safe drinking water standards. The water system pumps groundwater from 10 hard rock wells with a capacity of about 780 gpm. The water is treated at two locations (Sierra Lakes and Forest Ridge) to remove iron and manganese. At the Sierra Lakes location the water is treated to remove uranium as well. Treated water and water not needing treatment are distributed through 13 pressure zones and 18 storage tanks.
On May 2002, Hillview submitted to the Merced District Office of the Drinking Water Field Operations Branch a revised engineering report for the proposed project and the focused environmental impact report. There are significant waste disposal issues associated with the uranium removal treatment process for the Sierra Lakes Treatment Plant upgrades that could not be satisfactorily resolved. Therefore, the project was revised to delete the uranium removal improvements and add the construction of five more wells to replace the source capacity of Sierra Lakes Well No. 4.
Hillview 's revised project as presented in its Revised Technical Project Report consists of:
New Wells
Includes the construction of ten new wells due to the elimination of the uranium treatment improvements. The wells would be constructed in an area that has not been previously utilized by Hillview. It has been confirmed that the area has the potential to produce good water. Hillview has drilled a test hole and obtained easements for at least five of the well sites and the transmission line from the well sites to the Sierra Lakes Treatment Plant. It is anticipated that the new wells will produce between 50 and 100 gpm each. The additional production capacity provided by the new wells is needed to meet current demands.
Raw Water Transmission Line
Approximately 11,500 feet of 8-inch diameter transmission line will be constructed from the new wells to the Sierra Lakes Treatment Plant. There will be no service connections off the transmission line. The line will allow the piping of raw water to a centralized treatment, storage, and distribution site. This will allow for optimization of the existing system to distribute treated water throughout the OSL system. The ability to treat the water from the new wells is necessary to assure that they can be used in the system.
Sierra Lakes Treatment Plant Upgrades
Several upgrades to the Sierra Lakes Treatment Plant are proposed. The upgrades include replacement of the media in the existing pressure filter and construction of new treatment facilities. The new treatment facilities would include up to four pressure filters (depending on new well production and water quality), 100,000-gallon reclamation tank, sludge press, booster pumps, telemetry system, and two standby generators. These improvements are necessary to remove iron and/or manganese from water currently produced from the existing wells and to improve production reliability. One standby generator will be used to provide backup power for the plant and the other standby generator will be used to provide backup power for Sierra Lakes Well No. 1A, which produces about 170 gpm. However, until the new wells are drilled and sampled, it is unknown whether additional filters will be needed. Therefore, the Sierra Lakes Treatment Plant upgrades would not be undertaken until the production and water quality of the new wells are determined. If all the upgrades are needed, it is anticipated that they will increase the treatment capacity of the treatment plant from 500 gpm to 1,000 gpm.
New Storage Tank
A 300,000-gallon steel tank is proposed to be constructed at the Sierra Lakes Treatment Plant. The tank would store treated water for distribution to Tank No. 1 or the Sierra Lakes area. Increased storage is necessary to reduce the duration of pumping from the new wells, thus conserving the resource. Since the Sierra Lakes Treatment Plant will provide 80 percent of the OSL water, additional storage is needed to optimize the operation of the distribution system.
Treated Water Transmission Line
To improve distribution of treated water, a new 12-inch diameter transmission line would be installed from the Sierra Lakes Treatment Plant to Tank No. 1, which is the system's main storage tank. Approximately 8,500 feet of 12-inch diameter PVC pipe would be installed and used exclusively as a transmission line with no service connections. The existing 6-inch diameter pipe, which has numerous service connections, would continue to be used as a water main. Improved distribution of the treated water from the Sierra Lakes Treatment Plant is necessary since this plant would account for more than 80 percent of OSL system's total production.
Forest Ridge Treatment Plant Upgrades
Three of Hillview's proposed upgrades to the Forest Ridge Treatment Plant are not eligible for funding at this time. The remaining elements consist of the addition of an automatic chlorination system and a standby generator. The eligible upgrades will improve the reliability of the treatment plant. The upgrades are necessary to assure a continuous production of water on a reliable basis.
On August 19, 2002, DHS issued its Notice of Application Acceptance for the Hillview project in the maximum amount of $3,408,447. Because the estimated total cost of the project is $4,084,241, the proposed project will be prioritized and funded as follows:
1. The focused EIR, new wells, new raw water transmission line, new storage tank, new treated water transmission line, and related project costs (i.e., land, easements, legal, administration, engineering, and contingencies) are the highest priority project components and must be funded and completed before the following lower priority project components are funded. The total estimated cost of the high priority project components is $2,293,741.
2. The Sierra Lakes Treatment Plant upgrades ($1,727,000) and the Forest Ridge Treatment Plant upgrades ($62,500) should be funded as prioritized below if funding is available after completion of the highest priority project components specified in Recommendation 2.a.
a. Installation of additional filters at the Sierra Lakes Plant as needed based on the production and water quality of the new wells.
b. Installation of a 100,000-gallon reclamation tank, sludge press, and booster pumps at the Sierra Lakes Plant.
c. Installation of two standby generators at the Sierra Lakes Plant.
d. Installation of a telemetry system at the Sierra Lakes Plant.
e. Installation of an automatic chlorination system at the Forest Ridge Plant.
f. Installation of a standby generator at the Forest Ridge Plant.
Total Estimate
Pursuant to the supplemental data to the Application, Hillview's estimated construction costs are as follows:
Description Total
Focused Environmental Impact Report $ 113,045
New Wells 460,000
New Raw Water Transmission Line 209,296
Sierra Lakes Treatment Plant Upgrade 1,727,000
New Storage Tank 180,000
New Treated Water Transmission Line 408,400
Forest Ridge Treatment Plant Upgrades 62,500
Land and Easements 145,000
Legal and Administration 125,000
Engineering 150,000
Contingencies 503,000
Total Project Cost $4,083,241
Due to the financial status of the OSL water system, DHS has set a maximum loan amount for Hillview of $3,408,447. Therefore, the project components as stated previously, are to be prioritized since the estimated cost of the proposed project is over $4.0 million.
Environmental Impact
Because Hillview is a private utility, DHS is the lead agency for compliance with environmental impact regulations. DHS has completed an initial study for the project and recommended the completion of a focused environmental impact report. DHS completed a Notice of Preparation of a Draft Environmental Impact report and an Administrative Draft EIR is now under review and comment.
