The Altoona Mine is an abandoned mercury mine located approximately 11 miles (as the crow flies) west of the town of Castella in Trinity County, California. The approximate geographic coordinates of the mine are 41 E 8'12.7" north latitude, 122 E 32'51" west longitude. The mine is located on private land within the Shasta-Trinity National Forest. The Shasta-Trinity National Forest is administered by the United States Forest Service (USFS). The Altoona Mine site is comprised of an abandoned and backfilled vertical mine, with an adjacent ore processing area, former retort areas, and waste rock and tailings piles. There are collapsed remains of wooden structures at the ore processing area, and other collapsed wooden structures are scattered about the periphery of the mine site. The mine was comprised of six levels of horizontal shafts which branch out from the main vertical shaft, and two levels of horizontal shafts which branch out from the second vertical shaft. The eight horizontal shafts comprise a total of over 10,000 linear feet. The mine is located on an escarpment which faces southeast. The ore processing area is located immediately southwest of the surmised location of the main adit, and tailings piles are located southeast (downhill) of the processing area. The base of the tailings piles is approximately 80 feet below the elevation of the processing area. Water from the mine flows from under the tailings piles, down Soda Creek to the east fork of the Trinity River, which is approximately one mile to the southeast of the mine. As no flowing water was found immediately upgradient of the mine, the water source of Soda Creek is assumed to be an underground source, which likely flows through mine passageways.
9/7/09 - EPA: 1; ERRS: 6
In the morning, ERRS worked on draining the repository leachate into drums, yielding 650 gallons. ERRS also continued work on installation of the biolog trench and the coir matting around the biolog. ERRS placed straw wattle in trenches which had been installed by CCC.
Work was completed on rolling up of coir matting on the repository, and the dozer completed track walking the repository to break up slopes which had hardened. The dozer was deconned and walked down to the USFS 25 for pickup by the vendor.
ERRS attempted to attach the lids of the leachate boxes, and made some progress, but still needed some additional supplies to complete. Work began on installation of the drainage trench near the mine shaft and some additional work was done on the roads.
9/8/09 - EPA: 1; ERRS: 6; SHN: 1
In the morning, ERRS worked on draining the repository leachate into drums, yielding 400 gallons. A storage pad was cleared for the 1000 gallon tank and the tank was placed in that area. The contents of the full drums were emptied into the tank, so that drums could be used again for leachate collection. Another 100 gallons of leachate was collected in the late afternoon.
ERRS also began work on organizing and covering remaining erosion control materials which will be utilized when mobilizing in October with the USFS abandoned mine lands crew.
ERRS resumed work to attach the lids of the leachate boxes, once additional supplies had arrived. Work was also completed on installation of the mine shaft area drainage channel.
The surveyor was on site and completed gathering data for the site, including footprint on the new screen plant.
9/9/09 - EPA: 1; ERRS: 6
In the morning, ERRS worked on emptying drums into the tank, for a total of 17 drums transferred into the storage tank. 150 gallons of leachate was collected from the repository.
ERRS packed the box van of supplies and equipment being returned to Sacramento, including the ATV, which was demobed at the end of the day. The trailer was picked up to haul the gator, and another EQM truck was loaded with supplies and equipment for demobilization
ERRS completed work on the lids of the leachate boxes and installed insulation. Coir mat installation was conducted on the west side of the repository.
9/10/09 - EPA: 1; ERRS: 4
In the morning, ERRS emptied leachate from the repository and transferred full drums into the connex box. Approximately 150 gallons of leachate was collected from the repository. Some work securing materials was conducted and straw wattles were temporarily placed on the southern edge of the repository cap to assist with erosion control, even though they were not permanently secured.
ERRS packed the remaining supplies and equipment into the truck demobing to Portland and into the RMs truck and trailer. The site was secured, gates locked and all remaining personnel departed.
9/11/09 - The EPA OSC and ERRS demobilized from Dunsmuir.
9/14/09 – The OSC met with REAC contractors at the EPA warehouse to discuss their scope of work for the week and coordinate on logistics. After meeting with the OSC, the REAC contractors mobilized to Dunsmuir.
9/15 – 9/19/09 – ERT and REAC were on site performing tasks associated with hydrology and materials transport. ERT worked on installation of monitoring equipment into Soda Gulch, for stream flow, turbidity and rain gauging. ERT installed moisture probes to determine moisture content of the newly restored areas. ERT monitored the stream flow in various locations and constructed a dam and weir in order for monitoring equipment. A malfunction in the monitoring equipment occurred which prevented the equipment from being placed on line.
9/20/09 – ERT and REAC demobilized from the site.
1. Amend and seed disturbed areas
2. Complete installation of erosion control measures.
3. Empty leachate collection system.
4. Winterize site and roads.
5. Hydroseed repository.
Empty leachate collection system.
Amendment of soils and installation of erosion control measures.
Prepare for demobe.
Leachate management.
Restoration and revegetation.
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