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| Reclamation of the Redex Mine Site on Whitewood Creek |
Lawrence County, South Dakota |
Primary Project Type: Instream Restoration
Secondary Type: Riparian Restoration |
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Whitewood Creek flood, 1995. During the 1995 flood, Whitewood Creek eroded late... |
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Primary Problem: Mining
Secondary Problem: Mining |
| Main Restoration Action(s): Channel reconstruction, Floodplain reconnection |
| Native Fish Focus: N/A |
Is this project part of a watershed scale restoration? No
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| Project Dates: Late summer 1996 to October 1996 |
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Initial Monitoring: 1995
Restoration Implementation:
Follow-up Monitoring: ongoing |
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Lead Agency:
Mussetter Engineering, Inc.
Owen Ayres and Associates, Inc.
Harner and Associates, Inc.
Chadwick Ecological Consultants, Inc.
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| Project Partners: |
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Homestake Mining Company, Inc.
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| Project Location:
The project reach of Whitewood Creek is located within Lawrence County, in the Black Hills of South Dakota. It is approximately two miles downstream of the town of Deadwood, and about 1.5 miles downstream from the Highway 14 crossing of Whitewood Creek.
To view a map of the project area, click here.
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Project Description:
The following case history is taken from the following reports:
DESIGN REPORT: Reclamation Plan for the Redex Mine Reach of Whitewood Creek, South Dakota, by Mussetter Engineering, Inc, et al. Prepared for Homestake Mining Company, Inc. July 1996.
WHITEWOOD CREEK RECLAMATION PLAN: A Sound Basis for Design. Mussetter, R.A., Harvey, M.D., Wolff, C.G., and McDowall, D.G., 2000. 2000 Joint Conference on Water Resources Engineering and Water Resources Planning and Management, Minneapolis, Minnesota, July 30-August 2.
Between 1880 and 1977, approximately 100 million metric tons of fine-grained, arsenic and sulphide mineral rich tailings from gold mining were discharged into the upper reaches of Whitewood Creek. The bulk of the tailings were deposited downstream in the approximately 22-mile-long reach between Crook City and the confluence with the Belle Fourche River. However, significant quantities of tailings were also deposited within the canyon-bound reach upstream of Crook City. The project reach is a wide and low gradient reach in the canyon that, over time, was a deposition zone for the sediment. Much of the transported sediment became chemically cemented by ferric arsenate as a result of oxidation of sulfide minerals, including arsenopyrite and pyrite.
The tailings and placer gold deposits in the primary project reach were intermittently placer-mined between the late 1930s and the late 1970s. In about 1939, the New Era Mining Company relocated the stream channel to the east side of the valley into the cemented alluvium, causing the creek to become over-steepened due to straightening of its course. The creek eventually broke through the cemented material, creating a headcut, sloughing banks and undercutting of the valley slope near the upstream end of the project reach. The relocated channel remained along the east side of the valley until a large flood in May 1995 caused the channel to avulse into one of five large pits (Pit 1) that were created in the middle of the valley during the mining operations. This pit was subsequently filled with sediment transported by the flood flows, and the new channel formed over the length of the pit.
During the 1995 flood, the alluvial fan at the mouth of an east bank tributary of Whitewood Creek incised, delivering a significant quantity of sediment to the creek. The creek also eroded laterally into an abandoned railroad embankment along the west bank near the downstream end of the project reach, resulting in the loss of an eight–foot section of the culvert that previously drained Slaughterhouse Gulch under the railroad grade embankment into Whitewood Creek.
Prior to the restoration project, Whitewood Creek was classified as a marginal, coldwater fishery, with limited populations of brown and brook trout due to low cover (five percent), high proportion of eroding banks, and riffle and run dominated channel characteristics – physical habitat features, which limit the quality of fish habitat. |
| Project Goals: The objectives of the design were to provide a geomorphically stable system in the project reach that would require minimal maintenance, maintain water quality in the creek, and enhance the habitat-limited trout fishery. The design would provide an integrated landscape in which both the valley floor and the channel of Whitewood Creek function to pass a range of flows and their sediment loads in a manner that would not cause excessive lateral channel erosion, significant deposition of the inflowing bedload material within the channel, or excessive erosion of the regraded and revegetated valley floor. Reconstruction of the toe of the railroad grade embankment and its subsequent protection, and improving fish habitat to the extent that is compatible with the stability requirements of the reach were also important goals of the project. |
| Project Methods:
The reclamation plan focused on the removal of visual evidence of mining-related activity, stabilization of certain reaches of the creek to prevent damage to existing infrastructure and habitat, minimization of reclamation-related construction disturbance, and restoration of the appearance and function of the area to as close to natural conditions as possible. The goals of the project were accomplished by: (1) Constructing a two-stage compound channel in some portions of the reach, with the lower stage sized to accommodate the mean annual flood (about 500 cubic feet per second) and the upper stage to accommodate the 8 to 10 year flood (about 2,000 cubic feet per second). (2) Constructing step drop structures (step-pool channels) to enhance the vertical stability of the channel and, secondarily, to enhance fish habitat. (3) Regrading and revegetating the floodplain to a physically stable configuration that would withstand out-of-bank flows in excess of the 2,000 cubic feet per second channel capacity. (4) Constructing buried rock spur dikes in the area of the pit that was filled-in during the May 1995 flood event to prevent erosion into the railroad embankment along the west side of the valley and to prevent erosion into the abandoned channel and east valley side. (5) Integrating the two east bank tributaries to the reach to prevent excessive deposition within the reclaimed channel or errosion of the floodplain. (6) Reconstructing the toe of the railroad embankment and providing adequate protection against further stream-induced erosion. (7) Constructing boulder edge lining to prevent excessive lateral erosion into the west floodplain. (8) Functionally integrating the reclaimed reach with the downstream, confined reach and the upstream, unmined reach. (9) Designing the channel bed and bank stabilization measures to incorporate fish habitat improvements where possible.
For details on reclamation methods and a reclamation video clip, click here.
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Restoration design included constructing step-drop structures (step-pool channel... |
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To prevent further erosion of an abandoned railroad embankment along the west ba... |
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| Monitoring Data and Collection
Methods: Fish and benthic invertebrate populations were sampled, and in-stream physical habitat measurements were taken by the South Dakota Department of Game, Fish and Parks (SDGFP) in September 1995 at two sites within the Redex Mine Reach of Whitewood Creek. This study was conducted for two purposes. The first was to determine if there was potential for biological enhancement of this section of Whitewood Creek in response to stream stabilization and habitat improvements. Data on the existing fish and invertebrate populations provided an evaluation of the potential effects of stream reclamation and the identification of factors that may have limited the expected positive effects of this stream work. The second purpose was to determine the current, baseline biological conditions in this section of stream in order to gauge changes that might occur in the future, after stream reclamation.
For more information on fish and macroinvertebrate monitoring, click here.
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| Was this project effective
and how was this determined? The goals of the reclamation efforts were achieved. Channel restructuring, valley floor regrading, and vegetation planting removed visual evidence of mining-related activity. Certain reaches of the creek were stabilized to prevent damage to existing infrastructure and habitat, and the appearance and function of the area was restored to as close to natural conditions as possible. However, fish population response has not been documented due to the lack of data collection following the initial baseline data collection in 1998. The South Dakota Department of Game, Fish and Parks conducted fish monitoring on the Redex reach of Whitewood Creek in the fall of 2005.
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(Before) Regrading and revegetating the floodplain was a considerable challenge ... |
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(After) Revegetation efforts on the regraded floodplain were a success.... |
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| Confounding Effects/Additional
Information: South Dakota Game, Fish and Parks conducted fish monitoring on the Redex reach of Whitewood Creek in the fall of 2005. However, there are at least three complicating variables that will make it difficult to quantify fish population response in the Redex Reach of Whitewood Creek: (1) The Black Hills are in the fifth or sixth year of a fairly significant drought and stream base flows have been reduced. (2) Homestake Mine is now closed and the water diversions from the Spearfish watershed that were routed through the mine and discharged into Whitewood Creek have ceased, thus reducing the base flow in Whitewood Creek. (3) The Lead-Deadwood Sanitary District has recently been pursuing a controversial approach to discharge of treated water during certain times of the year creating significant short-term pulses in the flow regime affecting the Redex reach. |
| Project
Specs (all specs are estimates): |
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Overall Estimated Cost:
$3 million
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| For more information on this project
contact: |
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Bob Mussetter, Mussetter Engineering, Email: bobm@mussei.com
Ron Koth, South Dakota Department of Game, Fish and Parks, Email: ron.koth@state.sd.us
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| This information
was collected by: Kristin Keith |
| Project last updated on: 6/27/2007 |
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