Comment Period: May 20 to June 20, 2016
SUBJECT: The U.S. Army Corps of Engineers, Sacramento District (Corps), is evaluating a permit application to expand coal mining operations at an existing coal mine located in western Colorado. The nature and extent of impacts are more specifically described below. This notice is to inform interested parties of the proposed activity and to solicit comments.
AUTHORITY: This application is being evaluated under Section 404 of the Clean Water Act for the discharge of dredged or fill material in waters of the United States.
APPLICANT: Tri-State Generation and Transmission Association, Inc., Attn: Barbara Walz, PO Box 33695, Denver, CO 80233, Phone: (303) 452-6111, Email: bwalz@tristategt.org
AGENT: Colowyo Coal Company, Attn: Mr. Tony Tennyson, 5731 Highway 13, Meeker, CO 81641, Phone: (970) 824-1532, Email: ttenyson@tristategt.org
LOCATION: The project area is located in and around five waterways (i.e., Taylor Creek, Wilson Creek, Jubb Creek, Little Collom Gulch, and Collom Gulch), 4 miles west of the existing Colowyo Mine, 5731 State Highway 13, approximately 22 miles north of the Town of Meeker, Sixth Principal Meridian, located centrally at 40.27076° north latitude, -107.90231° west longitude, Moffat County, Colorado.
PROJECT NEED AND PURPOSE: The applicant states that permitted coal seams at the existing mine site will be depleted (mined out) in the near future, and expanded coal mining operations are necessary to 1) meet company production demands and 2) provide coal for the regions numerous coal-powered power plants. Further, the applicant has stated that once the existing permitted coal resource is exhausted, there will be a negative impact to the local economies of Moffat and Rio Blanco Counties, where the majority of the tax base is derived from the extraction of natural resources. Based on available information, the Corps has determined the basic project purpose is expansion of an existing coal mining operation.
PROJECT DESCRIPTION: The applicant is proposing to expand an existing surface coal mining operation. The applicant’s preferred alternative, known as the Collom Expansion project, would result in the filling of 0.16 acre of wetlands, 0.26 acre of open-water stock ponds, and 0.38 acre (11,643 linear feet) of ephemeral drainages (0.80 acre total impact to waters of the U.S.). These impacts will occur in Collom Gulch, Little Collum Gulch, Wilson Creek, and Jubb Creek. The Collom Pit would be mined with overburden material stockpiled in Little Collom Gulch. The project includes two road-crossings for the Collom Haul Road across Jubb and Wilson Creeks. A total of 0.80 acre of waters of the U.S. would be impacted under this alternative.
The volume of fill required to construct the culvert crossings across Jubb Creek and Wilson Creek is approximately 4,000 cubic yards. The fill used in the mine area to replace the wetlands would consist of backfilled non-toxic spoil material overlain with 4 inches to 4 feet of salvaged topsoil depending upon slope position and the vegetative community to be established. In addition, a rock-lined channel would be built to convey water through the reclaimed area to serve as a replacement drainage for Little Collom Gulch.
The area to be mined within the Collom Pit covers an area of two long ridge lines at about 7,900 feet in elevation which is bisected by a 100 to 200 feet deep valley formed by the ephemeral stream channel of Little Collom Gulch. Ultimately the Collom Pit is expected to encompass approximately 880 acres and may be 600 to 650 feet deep in places. The proposed disturbance areas, with the exception of the wetlands and other waters of the U. S. located in, abutting, and adjacent to Collom Gulch, Little Collom Gulch, Jubb Creek, Taylor Creek, and Wilson Creek, are uplands and will be returned to upland conditions via the reclamation process.
Initially, Colowyo will construct a downstream sediment control pond and sump near the eventual toe of the proposed temporary spoil pile in order to establish sediment control in the area. Temporary and permanent drainage ditches of various types, functions, and configurations will be constructed to control erosion, route stormwater from undisturbed areas around disturbed areas, and capture stormwater generated from areas within the disturbance footprint.
Prior to any mining related disturbances, topsoil will be removed from planned disturbance areas and redistributed or stockpiled as necessary to satisfy the needs of the reclamation timetable. Mining is anticipated to be conducted in an up-dip direction (north to south) using conventional truck/shovel mining techniques with the potential for utilization of draglines and highwall mining equipment.
After the removal of overburden (interburden), individual coal seams would be exposed and cleaned using auxiliary equipment. The coal seams would then either be drilled and shot with explosives, or ripped to prepare the coal for loading and removal. Once the coal has been prepared for loading, a rubber-tired front-end loader or excavator will load the coal into haulage trucks. Haulage trucks will transport the coal via in-pit haulage routes to the primary crusher located just outside the pit. Coal from the primary crusher will be loaded into trucks and transported on a paved haulage road to the train loadout.
The project is scheduled to commence in 2016 with final reclamation in approximately 2034.
ADDITIONAL INFORMATION:
Background and History: Coal mining activity (primarily underground mining initially) has occurred in the area since the late 1800’s. Commercial surface coal mining activities began in this area in the mid-1970’s.
The predominant land uses identified in the project area are rangeland and as habitat for fish and wildlife. Additional land-uses in the vicinity of the project area include coal exploration and recreation.
The applicant has prepared a functional assessment (FACWet) of the project area’s wetlands. The Composite Functional Index Score for emergent wetlands at the Jubb Creek and Wilson Creek crossings are “Highly Functioning,” while emergent wetland associated with Little Collom Gulch and area stock ponds are rated “Functioning Impaired.”
Area Description: The 2,384-acre project Area occupies the south-central portion of the Lower Yampa River basin in northwestern Colorado. Elevations in this area range from approximately 6,400 feet above mean seal level (msl) to approximately 8,567 feet msl. Headwater stream gradients typically range from 3 to 5 percent, and are generally 1 to 3 percent along the colluvial floodplains lower in the watershed. Adjacent upland drainage side slopes range from moderately steep to steep (>35%), whereas the benches between drainages generally exhibit flatter slopes with a northeasterly aspect between 1 and 5 percent.
The climate in the region is semi-arid, characterized by low precipitation, large daily temperature fluctuations, low humidity, and abundant sunshine. Prevailing winds are westerly. The growing season is approximately 90 days. Precipitation averages about 18 inches per year, with most precipitation falling in the form of snow generally between the months of October and April. Surface flows in the general area are primarily ephemeral and dominated by runoff events resulting from either snowmelt or rainfall.
Vegetative communities in this landscape include sagebrush-perennial grass, and other shrub/woodland types such as oak brush, snowberry, serviceberry, mountain mahogany, pinyon-juniper, and aspen. Vegetation cover ranges between 35 and 75 percent. A few aspen groves grow at the higher elevations and scattered juniper trees occur in the northern part of the Project Area. Emergent wetlands occur along the fringes of stock ponds, Little Collom Gulch, and Wilson and Jubb creeks and their tributaries
Alternatives: The following list of alternatives has been provided by the applicant, and has not been vetted or otherwise evaluated at this time. The Corps will perform an alternatives analysis of both onsite and offsite alternatives as part of the project evaluation.
Alternative A (Maximized Collom Pit and Little Collom X Pit): Under Alternative A, the entire extent of the Collom Pit and Little Collom X Pit would be mined to the largest extent that is economically feasible for coal removal. A total of 2.49 acres of waters of the U.S. would be impacted under this alternative, including the placement of overburden material within the reaches of Little Collom Gulch, and two road-crossings constructed across Jubb and Wilson Creeks. Additional quantitative impacts of this alternative include increased interception of rain and snowmelt, construction of sediment control structures, increased impacts to confined and unconfined groundwater aquifers, reduction in the base flows associated with Jubb Creek and Collom Gulch (which support wetlands downstream), and impacts to downstream water rights. This alternative has a total disturbance footprint of 3,315 acres, mining approximately 184 million tons from the larger Collom Pit and approximately 4 million tons from the Little Collom X Pit.
Alternative B (Collom Mine and Little Collom X Pit): This alternative includes a plan to mine the Collom Pit, place overburden material in a temporary stockpile within the reaches of Little Collom Gulch, mine the Little Collom X Pit, and construct two road-crossings across Jubb and Wilson Creeks. A total of 1.19 acres of waters of the U.S. would be impacted under this alternative. Under this alternative the overall pit shell for the Collom Pit was minimized to reduce impacts from mining within the watersheds of Jubb Creek and Collom Gulch. Additional quantitative impacts of this alternative would include increased interception of rain and snowmelt, increased impacts to confined and unconfined groundwater aquifers, and temporary reduction in the base flows associated with Little Collom Gulch, which support wetlands downstream. This alternative has a total disturbance footprint of 2,071 acres, mining approximately 60 million tons from the Collom Pit and approximately 4 million tons from the Little Collom X Pit. To avoid and minimize impacts, this alternative was eliminated from consideration to due impacts to a Greater Sage Grouse lek. Environmental analyses determined that a significant impact would occur to Greater Sage Grouse if this alternative was implemented and through a cooperative effort between the OSM, the Bureau of Land Management (BLM), and Colowyo this alternative was eliminated.
Alternative C (Collom Mine, Applicant preferred): The applicants preferred alternative, as described above under PROJECT DESCRIPTION, would impact a total of 0.80 acre of waters of the U.S. Additional quantitative impacts of this alternative would include increased interception of rain and snowmelt, increased impacts to confined and unconfined groundwater aquifers, and temporary reduction in the base flows associated with Little Collom Gulch, which support wetlands downstream. This alternative has a total disturbance footprint of 2,384 acres, and operations would mine approximately 60 million tons of coal from the Collom Pit.
Alternative D (No Action): Under Action D, no impacts to waters of the U.S. would occur. To implement a viable mine plan to avoid all impacts to wetlands, the temporary spoil piles would be stockpiled on the upland portions of the ridges. This would require a redesign of the temporary stockpile into two stockpiles (84 million cubic yards each). The overburden material in the stockpiles would not be able to be constructed to a high elevation due to geotechnical stability of being constructed on an upland feature without the valley walls to help stabilize the temporary stockpile. To accommodate the revised disturbance from the two temporary stockpiles, it is estimated that 7 sediment ponds and associated ditches would be constructed to route surface water runoff from disturbed areas to the sediment ponds. The applicant would avoid and mine around aquatic resources and not directly impact them. Under this alternative, approximately 20% of the Collom Pit could be mined; however, this alternative is considered cost-prohibitive by the applicant.
MITIGATION: The applicant’s preferred alternative was B; however, this alternative was eliminated to mitigate for a Greater Sage Grouse lek that is in close proximity to the Little Collom X Pit. Indirect and direct impacts from mining activities were considered, and Colowyo was required to eliminate mining of the Little Collom X Pit, reconfigure the temporary stockpile, and finalize necessary mining related disturbances. With these changes Colowyo was able to mitigate impacts to the Greater Sage Grouse, and decrease waters of the U.S. impacts from 1.19 acres to 0.80 acre, avoiding 4,523 linear-feet of Little Collom Gulch.
Regulations of the Colorado Mined Land Reclamation Board for Coal Mining require reclamation to a post-mine surface that is similar to the pre-mining condition. Please see Figure 12 for the post-mining topography for the project area. Characteristics of the postmine surface will vary due to regulatory requirements and general site and operating limitations. Overall, the wetlands impacted by the Project would be reconstructed in a manner similar to the pre-mine condition. Additionally, post-mining reclamation land uses will mirror pre-mining land uses.
The Corps requires that applicants consider and use all reasonable and practical measures to avoid and minimize impacts to aquatic resources. The applicant has proposed purchasing of mitigation credits from the Finger Rock Preserve mitigation bank to offset impacts to waters of the U.S.
OTHER GOVERNMENTAL AUTHORIZATIONS: Authorization from the Colorado Department of Reclamation, Mining and Safety (CDRMS) and the federal Office of Surface Mining (OSM) are required for the proposed activity. The Colorado Department of Public Health and Environment (CDPHE) issued Section 401 Water Quality Certification for the proposed activity on April 22, 2016.
HISTORIC PROPERTIES: A Class III cultural resource inventory has been performed within the Area of Potential Effects (APE), and consultation with the State Historic Preservation Office (SHPO), as required under the National Historic Preservation Act (NHPA), has been initiated by the OSM. In order to insure compliance with the NHPA, a Corps permit will not be issued until all required consultation is completed, and any agreements or stipulations which may result from that consultation are finalized.
ENDANGERED SPECIES: Formal consultation, as required under Section 7 of Endangered Species Act (ESA), and request for concurrence with effects determinations for 11 plant and animal species, has been reinitiated with the U.S. Fish and Wildlife Service (USFWS) by the OSM. The USFWS has expressed concern regarding the deposition of mercury and selenium as byproducts from the combustion of coal at the Craig Generating Station in Craig, Colorado, which were not considered in previous consultations and are being analyzed as an indirect effect of mining. In order to insure compliance with the ESA, a Corps’ permit will not be issued until all required consultation is completed, and any agreements or stipulations which may result from that consultation are finalized.
EVALUATION FACTORS: The decision whether to issue a permit will be based on an evaluation of the probable impacts, including cumulative impacts, of the described activity on the public interest. That decision will reflect the national concern for both protection and utilization of important resources. The benefit, which reasonably may be expected to accrue from the described activity, must be balanced against its reasonably foreseeable detriments. All factors which may be relevant to the described activity will be considered, including the cumulative effects thereof; among those are conservation, economics, aesthetics, general environmental concerns, wetlands, historic properties, fish and wildlife values, flood hazards, floodplain values, land use, navigation, shoreline erosion and accretion, recreation, water supply and conservation, water quality, energy needs, safety, food and fiber production, mineral needs, consideration of property ownership and, in general, the needs and welfare of the people. The activity's impact on the public interest will include application of the Section 404(b)(1) guidelines promulgated by the Administrator, Environmental Protection Agency (40 CFR Part 230).
The Corps is soliciting comments from the public, Federal, State, and local agencies and officials, Indian tribes, and other interested parties in order to consider and evaluate the impacts of this proposed activity. Any comments received will be considered by the Corps to determine whether to issue, modify, condition, or deny a permit for this proposal. To make this decision, comments are used to assess impacts on endangered species, historic properties, water quality, general environmental effects, and other public interest factors listed above. Comments are used in the preparation of an Environmental Assessment and/or an Environmental Impact Statement pursuant to the National Environmental Policy Act. Comments are also used to determine the need for a public hearing and to determine the overall public interest of the proposed activity.
SUBMITTING COMMENTS: Written comments, referencing Public Notice SPK-2012-00515, must be submitted to the office listed below on or before June 20, 2016.
Travis Morse, Senior Project Manager
US Army Corps of Engineers, Sacramento District
Colorado West Regulatory Branch
400 Rood Avenue, Room 224
Grand Junction, CO 81501
Phone: 970-243-1199, ext. 14
Email: W.Travis.Morse@usace.army.mil
The Corps is particularly interested in receiving comments related to the proposal's probable impacts on the affected aquatic environment and the secondary and cumulative effects. Anyone may request, in writing, that a public hearing be held to consider this application. Requests shall specifically state, with particularity, the reason(s) for holding a public hearing. If the Corps determines that the information received in response to this notice is inadequate for thorough evaluation, a public hearing may be warranted. If a public hearing is warranted, interested parties will be notified of the time, date, and location. Please note that all comment letters received are subject to release to the public through the Freedom of Information Act. If you have questions or need additional information please contact the applicant or the Corps' project manager Travis Morse at 970-243-1199 ext. 14, or by email at W.Travis.Morse@usace.army.mil.
8 Attachments:
- Figure 1: Location Map
- Figure 2: Collom Project
- Figure 4: Jubb & Wilson Creek Crossing
- Figure 8: Collom Pit Cross Section Locations
- Figure 9: Collom Pit Cross Sections
- Figure 10: Temporary Spoil Pile Cross Section Locations
- Figure 11: Temporary Spoil Pile Cross Sections
- Figure 12: Collom Project Post-Mining