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In 1992, the EPA (Environmental Protection Agency), under the Clean Air Act, awarded
the Alaskan Department of Environmental Conservation a grant to fund the reclamation of an
abandoned placer mine. This project was called the “abandoned placer
reclamation project.”
For the past 100 years, Alaska has been the site for extensive mining. The
majority of active mining in Alaska occurs on state and federal land. The US Mining
Laws, specifically 43 CFR 3809 on the federal level, define the reclamation standards for
mines operated since 1981. An Alaskan State law regulates the reclamation procedures
on private, state, and federal lands for mines operated since mid-October 1991. The
Department of Natural Resources and Division of Water and Mining issued the reclamation
requirements. Briefly, it required all mined land be returned to a stable state,
that post-mining erosion be minimized, and that the potential for natural revegetation be
enhanced. Before a mining permit can be issued, the mining company must first submit
a plan for reclamation.
Many of Alaska’s abandoned mines are not covered under existing laws.
Unreclaimed settling ponds and disturbed areas are a likely source for nonpoint
pollution. Many of these abandoned mine sites are in popular and heavily traveled
areas. It is for this reason that many people may have a negative viewpoint of the
mining industry.
The abandoned placer reclamation project was a cooperative effort among many
governmental agencies on both the state and federal levels. The selected site was
located on the Steese Highway, which connects Fairbanks with Central and Circle
City. This area was chosen for several reasons. The most significant of these
was the fact that this was a heavily mined area in the past, and the results of the mining
activity were visible along a heavily traveled stretch of highway. In addition, the
location of this site favored the development of a recreational area as a result of the
reclamation.
Goals of the project were defined from its beginning. These included: data and
cost analysis, determining the impact mining/reclamation had on water quality,
establishing guidelines for methods and techniques, documentation of the reclamation
process, and monitoring the site for several years afterward.
Monitoring stations were constructed at several different locations. These
stations contained equipment to analyze the discharge and total amounts of suspended
sediments, in addition to testing the water quality. Reclamation plans were designed
to stabilize the channels to accommodate the sediment and discharge loads. Other
research areas were implemented to sample the natural vegetation on the abandoned
site. Soil samples were taken and analyzed for pH, extractable nitrogen, phosphorus
and potassium, cation-exchange capacity, organic matter, electrical conductivity, and
particle-size distribution.
40+ plant species were observed to have naturally colonized the
site. It was determined that although the plant species naturally colonized
this territory, the rate at which this occurred may have been much slower than in
comparable southern areas. In addition, data indicated a lack of nutrients in the
floodplains of the mined areas. It was hypothesized that the planting of grasses and
willows would contribute to the quality of the soil, stabilize the bank and improve the
appearance of the site. This project was successful in the reclamation of this
site. In addition, because of the in-depth analysis, reclamation techniques were
formatted for mines in northern climates.
Source: SME CD, Technical articles from Mining Engineering magazine
1980-1996. Volume II: Article: “Reclaiming an abandoned placer mine site in
Alaska” by Michael G. Nelson, Edmond C. Packee Jr. Dot J. Helm.
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