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Fall 2003 Since the last issue of PITWATCH, Montana Resources has decided to resume operations. With the mine going again and with the water treatment plant coming on line, there have been many questions from the community. Here are some answers to reader questions. Q: How much total water went into the Berkeley Pit since the suspension of mining at Montana Resources? A: About 7.5 billion gallons of water or an average of 6 mgd has gone into the Pit since MR suspended operations. An average of 3.4 mgd of this total was from the underground workings and storm water flow. An average of 2.6 mgd of this total was from the Horseshoe Bend discharge. Q: How much water will go into the Pit once mining operations resume completely and the water treatment facility is operating? A: The Horseshoe Bend drainage flow will be treated in the new treatment plant, and presently, this water will be entirely consumed in the mining operations. The remaining 3.4 mgd of flow from the underground workings and storm water flow will still flow into the Pit contributing to the rising level there. Eventually, when the water level approaches 5,410' above sea level (expected about 2018), water will have to be pumped from the Berkeley Pit and treated at the Horseshoe Bend facility. Having the plant in place provides assurance that the capability is there when it becomes necessary to treat Pit water. Q: Where will the treated water go? A: Current plans are to treat
the entire Horseshoe Bend drainage flow at the treatment plant,
and then route all of the treated water to the concentrator for
use in mine operations. As a result, and for as long as the treated
water is used in the mining circuit, there will be no discharge
off-site. In the event the mine was to suspend operations again,
Horseshoe Bend drainage water would be treated to discharge standards
at the plant. Then it would be transported by a pipeline, being
constructed along the historic Silver Bow Creek channel (Metro
Storm Drain), to its confluence with Blacktail Creek, just west
of the Visitor's Center on George Street. Priority Soils: The Other Superfund
cleanup project in the Butte area Where is the Butte Priority Soils cleanup site? Generally, the project includes the residential yards and mine dumps on the Butte Hill and in Walkerville, and the water drainages weaving down the Hill to Silver Bow Creek. The site is about five square miles and includes most of the urban area from Walkerville on the north to Silver Bow Creek on the south, along with the Clark Tailings below Timber Butte. It's also important to understand what the Priority Soils does NOT include. It's separate from the Berkeley Pit and underground mine flooding project, which, as we've reported in PITWATCH for several years, is the responsibility of Arco and Montana Resources. The Priority Soils is also separate from the Montana Pole cleanup and the Streamside Tailings project along Silver Bow Creek, both of which are ongoing and the responsibility of Montana Department of Environmental Quality. In the big picture, all these cleanup activities will have to fit together, but for now, Priority Soils stands alone. What is the cleanup task? The job is two-fold: 1) to eliminate direct contact with mine waste on the Hill, thus protecting human health; and 2) to prevent the heavy metals in those mine waste materials from getting into storm water and groundwater and finding their way to Silver Bow Creek, thereby protecting life in the stream and the DEQ's $85 million creek cleanup project. Is some work already complete? Yes. In fact, a substantial amount of the cleanup of Priority Soils has occurred - about $50 million of work by current estimates. Over the past 15 years, several projects have been completed, with the understanding that all this work will be reviewed as part of the final decision. Major projects (refer to the map) include: the Alice Pit/Dump (1998); several areas in Walkerville (1988, 1994, 2002); the Missoula Gulch, Buffalo Gulch and Kelley ditches and retention ponds (1997-99); railroad corridors (2001-03); and Lower Area One, including the reconstructed Silver Bow Creek, the Colorado Tailings removal, and the Clark Tailings project (1993-2000). In all, more than 175 mine
dumps covering more than 400 acres have been partially removed
and capped, and more than 180 residential yards have been cleaned
up (lead soil removals). The caps generally consist of placing
18" of clean soil materials with organic amendments over
the wastes and planting native vegetation to hold the soil in
place and minimize erosion. To complement the caps, a system
of storm water collection facilities - the new drainage ditches
and retention ponds - has been installed to collect water that
may still contain heavy metals and prevent those contaminants
from reaching Silver Bow Creek. In addition to cleanups, other issues include deciding what type of water treatment system should be used to ensure groundwater, surface water or storm water leaving the area will not pollute Silver Bow Creek heading west of town. Another big decision will be to determine whether the projects already completed were done satisfactorily and will be permanent, or whether additional work is needed. Perhaps the most important issue is to determine how the reclaimed areas and water management facilities will perform in the long term and be effectively maintained. As part of the Record of Decision, it will be critical to set the right performance standards for treatment and long-term care, and then determine how much money it will take to get the job done properly. Is Butte on the hook for the Priority Soils cleanup? Unlike every other cleanup around Butte, where the citizens have been protected from any Superfund liability, Butte-Silver Bow was named as a Potentially Responsible Party or PRP to conduct the Priority Soils cleanup. In 1990, EPA decided that since the publicly owned storm water system carried wastes off the Hill to the creek, the community was partly liable for the problem. However, Arco is also a PRP
for Priority Soils, and for the most part over the past 15 years,
Arco has paid all costs for cleanup work. As part of the upcoming
Record of Decision and then a Consent Decree for the Priority
Soils project, Butte's "share" will be determined. The Committee awarded $50 savings bonds to four grade-school students and a $250 bond to one high school student who competed in the 2003 Montana Tech Science and Engineering Fair. Each of their Fair projects explored important topics related to the Berkeley Pit and mine waste cleanup technologies. The Committee will offer awards again at the 2004 Science Fair, and students are encouraged to choose projects related to the Pit and mine waste cleanup for that competition.
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Also in 2004, the Committee will
introduce new educational posters, which will be displayed in
special stands on the deck of the viewing stand. The Committee
and staff have finalized details for four posters. The first
is a historical look at the types of mining used in the Butte
area. The second examines the history of the Berkeley Pit itself,
and offers some wonderful images of Butte. Poster three focuses
on the water in the pit, and the science and history of how it
got there. The pictures on poster three offer a visual timeline
of water rising in the pit. Finally, the fourth poster focuses
on cleanup at the Pit, water quality and treatment and microorganisms
in the Pit. 
