Jackpot - Uranium Mitigation & Water System Improvements Project
BACKGROUND
 The Town of Jackpot is located on US 93 at the Idaho-Nevada border about 50 miles south of Twin Falls, Idaho. This community was the first casino boomtown in Nevada after Las Vegas. There are approximately 1,250 permanent residents in Jackpot now, and although the town lacks a cemetery, it does have a school, a golf course, a magnificent enclosed swimming pool, tennis courts, over 100 RV spaces and an airport. Collectively Jackpot-area casinos are the largest employer in southern Idaho.
The Town currently has 5 wells. Wells 1, 2, and 3 together only provide approximately 1,200 gpm. Well 4 is currently disconnected from the system and provides irrigation for the golf course only. Well 5 is the largest well and operates at approximately 2,400 gpm. Chlorination is supplied to the distribution system at Wells 1 and 5.
The system has 1,400,000 gallons of storage across three storage tanks: Tank #1 - 1-million gallons, Tank #2 - 300,000-gallon, and Tank #3 - 100,000-gallon. The Jackpot water system was inspected by the Nevada Bureau of Safe Drinking Water (BSDW) in June, 2007, and the BSDW observed that the concrete underground Tank No. 1 has openings that could allow contamination to enter the tank. They recommend abandonment and/or replacement of the underground concrete tank due to a cracked seam, visible rebar, and holes in the tank.
In March 2004, High Desert Engineering prepared a "Water System Master Plan" for the Town of Jackpot. In July 2008, ECO:LOGIC prepared a Preliminary Engineering Report that updated costs and alternatives for the water system to come into compliance with the requirements of the Nevada Administrative Code (NAC). Costs were again up-dated in June 2009.
Well 5 is powered by a 250-horsepower vertical, hollowshaft motor. The motor is started across-the-line without reduced voltage starting and causes voltage dips in the vicinity of the well on start-up. It also contributes to high power bills due to the "demand charge" portion of the electric bill, which is based on the peak power consumption observed at the service during the start-up period. In addition to the voltage dips, the start-up can contribute to hydraulic surges in the distribution system.
Water quality testing has revealed that uranium is present in all of the Town wells and is above the drinking water standard in Well 2. Uranium is a naturally occurring element found at low levels in virtually all rock, soil and water. Alpha radiation is not particularly dangerous unless ingested into the body, which is why uranium is a concern in drinking water.
The existing water system is unmetered. Based on the average day usage during the summer months, the usage rated per equivalent residential unit appears to be nearly double the typical peak demand for systems of similar size and environmental conditions.
Under the NAC, the Jackpot system needs to have a total capacity sufficient that it can supply: (1) maximum day demand, fire flow, and fire demand when all the facilities of the system are functioning; and (2) average day demand, fire flow and fire demand when the most productive well of the system is not functioning. Based on the analysis, the system has adequate supply with all existing facilities operating to meet the maximum day demand scenario. However, the system cannot meet the average summer day demand with the largest well (Well 5) out of service.
If the Town elects to do nothing, the system will remain in non-compliance with NAC requirements for system pressure and the ability to operate with the largest well out of service. Due to the limited amount of storage available, it is also likely that a sustained power outage in the summer could require emergency actions by the operator to avoid losing all storage and loss of system pressure. Jackpot receives its power from Raft River Electric in Malta, Idaho, and according to residents, when a power outage does occur it is not uncommon for the electricity to be off for several hours at a time. If a prolonged power outage were to occur in July or August, as often happens, and the well with the standby engine generator were off line for some reason, the system would not be able to meet the demand and would rapidly deplete the available storage. Well 2 has been determined to be above the uranium MCL, and cannot be used without some form of mitigation. These conditions result in a deficiency of adequate water supply to the Town.
PROJECT DESCRIPTION
The recommended project includes a new well (Well 6) to allow the system to operate and meet NAC requirements with the current largest well (Well 5) off-line, two small booster pumps to help alleviate low pressures in the north of the system, and abandonment of existing Well 2 which exceeds the uranium MCL.
The project plans to drill Well 6 within approximately 1,000 feet of the existing Well 5. The geology and hydrogeology of this area is relatively complex. Recent studies have shown inconsistencies in the subsurface flow. Well logs in the vicinity of Well 4 and Well 5 indicate that the areas consist of either volcanic ash or sandstone to a depth of approximately 150 feet, underlain predominantly by massive or fractured rhyolite. The upper ash and sandstone are not productive and screened intervals are limited to the fractured rhyolite below a depth of 400 feet. Given the uncertainties, an exploratory well will be constructed, test pumped and sampled prior to installing a new production well.
Well 2 is above the MCL for uranium. This well will have to be blended or treated before the water can be used in the system. If the new Well 6 is successfully constructed, this will provide adequate supply so that the water system can afford to abandon Well 2. Since regulations can change in the future, and it is possible that the blending option may no longer be viable; therefore, it is recommended that this well be properly abandoned and the water rights relocated to the new Well 6.
Two small booster pumps, at the new Well 6 site, are included in the project to alleviate low pressures in the northern portion of the community. The two pumps will not be designed to provide fire flow, since this can be provided from the existing system through a check valve. The installation of these pumps will create two pressure zones to avoid the low pressure issues in the northeast portions of the town.
Well 5 will also be provided standby power through a cable run from the proposed Well 6 back to Well 5. In this fashion, either well will be able to be run by the generator.
In July 2009, the Board approved a grant for a uranium mitigation & water system improvements project for the Town of Jackpot in an amount not to exceed $1,432,000 (approximately 50% of the total eligible project cost of $2,864,000). The match funding is provided by the Drinking Water State Revolving Loan Fund (DWSRF) and the US Department of Agriculture - Rural Development. The DWSRF principal forgiveness loan are funds provided by the federal government under the American Recovery and Reinvestment Act of 2009 (ARRA).
PROJECT STATUS
The new well was bid in January 2010 with the contract being awarded to Humboldt Drilling. Drilling is expected to begin in February 2010.
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