Lander County - Town of Battle Mountain Arsenic Mitigation PER
BACKGROUND
 Battle Mountain is located approximately 225 miles northeast of Reno and is the county seat for Lander County. Lander County is named after General Fredrick W. Lander who was a prominent road builder for the Department of the Interior. He played an important role in negotiating a peace settlement with American Indians during the Pyramid Lake War of 1860. The Lander County region attracted prospectors fanning out across the Great Basin after the 1859 discovery of the Comstock Lode. In October 1868, the railroad established Reese River Siding and made Argenta its principal station and point of departure for the busy mining camps to the south. In January 1870, Argenta was moved five miles west, Reese River Siding was renamed Battle Mountain Switch, and the town of Battle Mountain sprang into existence. Nevada's most prominent mining camps in the 1870s were served by the railroad at Battle Mountain.
From 1880 to 1938, Battle Mountain was the operating headquarters for the Nevada Central Railroad, as well as the Battle Mountain and Lewis Railroad (1881-1890). The town's first copper boom developed in 1897 in the Galena (Battle Mountain) Range. By the middle 1930s, most of the mines that generated traffic at Battle Mountain were shut down and boarded up. Some 30 years later, the DuVal Company (now known as the Battle Mountain Gold Company) invested more than $20 million in the development of large copper ore bodies in the hills to the south. Battle Mountain became a boomtown, the schools overflowed, the sewer system burst its seams and the municipal wells started pumping sand.
Battle Mountain's mines now produce gold instead of copper and significant improvements have been made to the water and sewer system. Battle Mountain receives its water supply from a confined aquifer source via three groundwater wells. Arsenic in the water supply is reported at concentrations of 18 to 23 micrograms per liter (µg/L - also known as parts per billion, ppb), which exceeds the new maximum contaminant level (MCL) for arsenic of 10 µg/L. In May 2007, the State Environmental Commission granted the Battle Mountain Water System an exemption from the arsenic compliance requirement until January 23, 2009. The Battle Mountain water system serves less than 3,300 people. Based on population served and average arsenic concentrations, Battle Mountain was eligible for an extension to their exemption. This extension expires in January 2011.
A Letter of Intent (LOI) for a construction project was approved by the Board for Financing Water Projects (Board) in 2002 for a three phase project that included replacement of the cast iron water mains and laterals, addition of a new storage tank and arsenic treatment with total eligible project costs of $3,995,875. The original construction grant for Phase I of the project was awarded to Lander County for the Battle Mountain water system in December 2002 in the amount of $1,581,924.80 (64.6% of the total eligible project cost of $2,448,800). The scope of the Phase I project was the replacement of the old, leaking, undersized water mains in Battle Mountain.
Match funding for the Phase 1 project was expected to come from the Corps of Engineers (COE) and the US Department of Agriculture - Rural Development (USDA-RD). Money from the COE was not made available for the water project, and the County approached the Board for additional grant funding. An increase in construction grant funding for Phase I was approved by the Board in November 2005. That increase in construction grant amount was $1,483,843.91 bringing the total grant to $3,065,768.71 (64.6% of the total eligible project cost of $4,745,772). Phase I of the project was completed in July 2007. Project savings totaling $147,350.03 were returned to the grant fund from this Phase 1 project to be made available to other projects. To review information from the Phase 1 project, click here.
 Original map of the area wells & arsenic concentrations (courtesy of Shaw Engineering). Click Here or on image to the left to Expand View
In the fall of 2007, research on project alternatives was started in support of a Preliminary Engineering Report (PER) for arsenic mitigation. A PER is necessary to apply for funding with the USDA-RD and the AB-198 grant program. In the course of that research, a potential new water source that met the arsenic standard was identified. Initial information on three wells located south of Battle Mountain indicates the availability of groundwater with arsenic levels less than 10 µg/L.
Hydrogeologists from Newmont Mining Corporation provided well data and hydrogeologic knowledge of the groundwater and groundwater quality south of Battle Mountain. Newmont pledged their support to Lander County officials regarding this project and made their hydrogeologists available to assist at no cost to the County. Newmont is also assisting in water rights research.
All of the available area well logs on file at the State Engineer's office were reviewed. This review indicated that similar layers of gravels and sands should be found within the basin area south of Battle Mountain and pumping capacities from this basin, meeting the town's demands, should be achievable with a minimum number of new wells. In order to verify water quality and quantity and complete an engineering estimate for a construction project, Battle Mountain needs to drill and test an exploratory well(s) south of Battle Mountain and possibly within Hydrographic Basin 059.
If the exploratory well drilling effort is successful and a non-treatment option is identified, the PER will include the results of a contaminate source inventory survey within 3,000 feet of the proposed well(s) and the new well location(s) will be incorporated into Battle Mountian's Wellhead Protection Plan and submitted to the Bureau of Water Pollution Control, Groundwater Protection Branch for endorsement.
Pilot testing is not currently planned in this PER. The Nevada Division of Environmental Protection, Bureau of Safe Drinking Water (BSDW), is requiring a pilot test of any proposed arsenic removal system unless there is substantial information on the water type and the County can demonstrate that pilot testing has previously been conducted on such water type with successful removal of the arsenic and been approved by the BSDW. If non-treatment options are eliminated, the PER must include arsenic pilot testing and both capital and operation/maintenance costs of applicable treatment.
Lander County applied for a PER grant under the AB-198 program to assist with the costs of exploratory well drilling south of town. The grant was approved by the Board on March 20, 2008, for an amount not exceed $117,000 (the eligible project costs were estimated to be $175,000). The County's budgeted amount for the PER is $58,000.
 Exploratory wells map (courtesy of Shaw Engineering). Click Here or on image to the left to Expand View
In the fall of 2008, two exploratory wells were drilled south of Battle Mountain. Both were drilled to a depth of approximately 800 feet. The first exploratory well encountered fractured bedrock at approximately 240 feet while the second remained primarily in alluvial sands and gravels to depth. The water quantity and quality at both wells met the requirements set forth for the project; however, concern over drawdown of the aquifer was expressed by private wells users in the area of these two wells.
An exploratory well(s) is currently being drilled in Hydrographic Basin 059. After the results of this drilling are received, the County and its engineers will need to review costs of a potential non-treatment option and decide if it pilot testing potential arsenic treatment for the existing water system wells should be pursued.
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