The Marysville Road/Silver Creek project is located within the boundaries of the Omaha District of the Corps of Engineers. The federal partner with the Corps for this project is the Federal Highway Administration. Other stakeholders include the Montana Department of Transportation, the Montana Department of Environmental Quality, and the Lewis and Clark County Public Works Department, Water Quality Protection District, and Weed Board.
Silver Creek and Marysville Road are located about 18 miles northwest of Helena. Silver Creek, which begins at the town of Marysville, runs eastward six miles before dumping into Prickly Pear Creek.
Project Description
Mining operations have impacted surface water quality in Silver Creek to the point where fish are not suitable for human consumption. Marysville Road is a gravel road that is narrow and winding in places, more so in the upper portion near Marysville. In a current project for MDT, Marysville Road will be widened and straightened first and then paved last. Work on widening and straightening will be done in sections. The Omaha District survey crew will install control points and survey in their locations in accordance with MDT specifications. In addition, the Omaha District survey crew will stake the boring locations for the roadbed fill sampling in the Montana State Plane Coordinate System NAD 83 datum. Soil borings will be continuously sampled from the road surface to a maximum depth of ten feet below ground surface or refusal for soil logging, geotechnical bag sampling, split-spoon blow counts, and composite analytical sampling. Twenty-one composite analytical samples and two quality control samples will be analyzed to determine whether or not road fill or road are potentially contributing to degradation of surface water quality.
Project Goals
One goal of this project was to establish survey control points throughout the drainage for use in design of the upgraded road and in ongoing environmental investigations occurring within the drainage. The second goal of the project was to identify possible areas of contamination from mine wastes possible used as road fill or road base that may be contributing to surface water contamination and will need to be removed during road reconstruction.
Current Status
A site visit occurred in late June 2002, and work plans were prepared based on discussions with stakeholders during that visit. The survey control points were installed by the Corps survey crew in August 2002. In the later half of that month, the Corps drill crew drilled all of the soil borings and sent chemical analytical samples to the laboratories. The Corps prepared the draft report. No comments were received, and the final report has been issued.
Existing Documents
As documents for this project become available, they will be provided in PDF format that can be accessed by clicking on the title of the document below. The General RAMS Work Plan and General Site Safety and Health Plan are referenced in project work plans. These documents may be accessed from menu to the left. Adobe Acrobat Reader is required to view these documents and may be downloaded free of charge from the Adobe Acrobat web site by clicking on Adobe Acrobat Reader above. Disclaimer: The appearance of an external hyperlink does not constitute endorsement by the U.S. Army Corps of Engineers (USACE) of this web site or the information, products, or services contained therein. USACE does not exercise any editorial control over the information you may find at this location.
Documents
1. Attachment 1
2. Attachment 2
3. Attachment 3
4. Attachment 4
5. Attachment 5
6. Attachment 6
7. Draft Report