Rocky Mountain Region; Grand Mesa, Uncompahgre and Gunnison National Forests; Grand Valley Ranger District; Mesa County, Colorado; Enlargement of Monument No. 1 and Hunter Reservoirs

AGENCY:

Forest Service, USDA.

ACTION:

Notice of intent to prepare a supplemental draft environmental impact statement.

SUMMARY:

The Grand Mesa, Uncompahgre and Gunnison National Forests (GMUG) intends to prepare a Supplement to the June 2007 Draft Environmental Impact Statement (DEIS) for the Hunter Reservoir Enlargement to also include enlargement of the Monument No. 1 Reservoir in the Proposed Action. The original notice of intent (NOI) for the Hunter Reservoir Enlargement was published in 70 FR 61781 on October 26, 2005; and the notice of availability (NOA) was published in 72 FR 39808 on July 20, 2007. Both reservoirs are owned by the Ute Water Conservancy District (Ute Water) and are located on National Forest System (NFS) lands in the Leon Creek watershed in the eastern portion of Mesa County, Colorado.

DATES:

Comments concerning the expanded scope of the analysis must be received by February 12, 2016. The supplemental DEIS is expected to be released in April 2016 for comment and the final environmental impact statement is expected in October 2016.

ADDRESSES:

Send written comments to Ute Water Reservoir Enlargement Projects, Grand Valley Ranger District, 2777 Crossroads Boulevard, Unit 1, Grand Junction, CO 81506. Comments may also be sent via email to comments-rocky-mountain-gmug-grande-valley@fs.fed.us, or via facsimile to 970-263-5819.

FOR FURTHER INFORMATION CONTACT:

Linda Bledsoe, Project Manager, at 970-263-5802 or via email at lbledsoe@fs.fed.us. Individuals who use telecommunication devices for the deaf (TDD) may call the Federal Information Relay Service (FIRS) at 1-800-877-8339 between 8 a.m. and 8 p.m., Eastern Time, Monday through Friday.

SUPPLEMENTARY INFORMATION:

A DEIS analyzing effects from the enlargement of Hunter Reservoir was issued in 2007. In 2009, Ute Water acquired the rights to Monument No. 1 Reservoir and subsequently commissioned a raw water study to be completed to analyze all of its water rights (storage and flow), how those rights are currently used and what additional rights or facilities might be needed in order for Ute Water to have sufficient water to meet increased municipal water demands for the next several decades. That study identified the need for additional high mountain storage, especially during times of drought. In February 2012, Ute Water submitted a proposal for the enlargement of Monument No. 1 Reservoir to be considered along with the enlargement of Hunter Reservoir.

With new alternatives and additional information brought forward, as well as the length of time that has passed since issuance of the DEIS in 2007, the Forest Service has determined that a supplemental draft environmental impact statement (SDEIS) that included both reservoir enlargement proposals was appropriate (FSH 1905.18.2, Chapter 10).

Purpose and Need for Action

The purpose and need for the Forest Service action on the Monument No. 1 and Hunter Reservoirs enlargement project is to respond to a request by the Ute Water Conservancy District for special use permits to expand the dams for these two reservoirs, which were submitted under the Forest Service's special use regulations (36 CFR 251.54).

Ute Water has proposed these expansions to meet the need for projected municipal water demand. Over the next 30 years, demand is expected to increase by about two and a half times the current amount of 14,300 acre-feet (AF). The Proposed Action is one of several actions that Ute Water has indicated it will need to meet its future demand for municipal water in its service area. Those actions include, but are not limited to, acquiring new water rights, perfecting existing water rights, and upgrading Ute's Colorado River pumping capacity and water treatment plant.

Proposed Action

Under the Proposed Action, the Forest Service would authorize the use of NFS lands by Ute Water to enlarge the existing Monument No. 1 and Hunter Reservoirs by increasing the size and height of the dams and spillways, along with the activities associated with those enlargements.

The reservoirs are located in Mesa County, Colorado, about 15 miles southeast of Collbran, Colorado. Hunter Reservoir is located in Section 27, T. 11 S., R. 93 W., 6th P.M. Monument No. 1 Reservoir is located in Sections 11 and 12, T. 11 S., R. 93 W., 6th P.M.

Construction associated with the Proposed Action would likely begin with the roads and trails, including necessary relocations, in advance of dam construction activities.

Both reservoirs hold irrigation water rights and are operated as irrigation reservoirs, meaning that the reservoirs fill each year and are typically drained in the summer after runoff has ended in order to irrigate the ranches below the forest boundary that have historically used the water. Depending on the amount of snowpack, the reservoirs fill during spring and early summer; and the water is stored in the reservoirs until later in the summer when the water is needed to irrigate the ranches or when a senior water rights holder places a call on the stream. The reservoirs are typically empty by late fall, and then the outlets are closed in order to capture water over the winter and the next spring.

For the enlargement of the two reservoirs, Ute Water applied for and received water rights decrees for primarily municipal uses, which would change how the reservoirs are operated. Because the reservoirs are located high in the watershed and existing senior water rights downstream are required to be satisfied first, it could take two to three years to fill each of the reservoirs. Once filled, Ute Water does not anticipate releasing the water stored in the reservoirs until it needs the water for municipal purposes or when there is a call on the stream by senior water rights holders downstream. Ute Water has identified the need for these reservoirs for periods of drought. The irrigation water rights would still be available for irrigation of the ranches, and that water would still be released. As the reservoirs would not be fully drained each year, the spring runoff would replace whatever irrigation water was released during the previous summer and the majority of runoff would generally pass through the reservoirs and spill downstream. Some municipal water could be released in late fall and/or winter in order to increase water quality in Plateau Creek prior to it being stored in the Jerry Creek Reservoirs and subsequent treatment as drinking water.

Access to both reservoir sites is primarily on the Park Creek Road (National Forest System Road (NFSR)) 262, which begins at Vega Reservoir below the forest boundary. The Forest Service holds an easement for the portion of the road crossing private lands from Vega Reservoir to the forest boundary.

Current Forest Service road management objectives (RMOs) classify NFSR 262 as a high clearance, four-wheel drive road; though most travel is presently done on all-terrain vehicles (ATVs). During spring runoff, NFSR 262, as well as other roads and trails in the area, are usually impassable because of high water at the stream crossings.

Substantial temporary and permanent improvements to the road would be required in order to accommodate all the traffic associated with the reservoir enlargements and to protect resources. Prior to dam construction, NFSR 262 would be narrowed back to its original width of 14 feet with 12-foot ditches and would have inter-visible (in sight of one another) pullouts. Drainage would be reestablished along the road, creek crossings would be hardened and surface rock added in order for the road to accommodate the increased traffic associated with the larger, heavier vehicles needed for construction of the reservoir enlargements. The intent of the road upgrades would be to improve the road structure and stability and not to allow for increased vehicle speeds.

Approximately three miles south of the forest boundary along NFSR 262, a “transfer area” would be established in an area that has historically been used as an ATV unloading area and livestock gathering site. The area is prone to holding water onsite and prevents proper drainage, which results in rutting and other resource damage. The area would be graded, sloped and hardened to allow for use of the site, while protecting or improving the condition of resources. This transfer area would be used for construction activities including unloading and storing material associated with both reservoir sites and would remain as a parking area for the Forest Service, permittees and the public following construction. The road would be upgraded to the transfer point to allow passage by street-worthy vehicles. From the transfer point to the reservoir sites, NFSR 262 would be used by off-road equipment and trucks, which would require less work on the road.

It is anticipated that road and trail work for both reservoirs would be done prior to the major construction work commencing on the reservoirs. The Park Creek Road (NFSR 262) to the Monument Trail (National Forest System Trail (NFST) 518) segment would need to be completed prior to the numerous construction vehicles accessing the construction site, although some breaching of the current reservoir could be done at the same time.

While construction work is ongoing at Monument Reservoir No. 1, improvements would be done on NFSR 262 to its intersection with the Hunter Reservoir Road (NFSR 280). Construction associated with the enlargement of the two reservoirs could last as long as 6 or 7 years; however, construction work on NFSR 262 should be complete within 3 or 4 years.

There would likely be delays for the public on the access routes to the reservoirs, but none of the routes would be closed to the public during construction activities.

Monument No. 1 Reservoir

Under the Proposed Action, Ute Water would enlarge the existing Monument No. 1 Reservoir by increasing the size and height of the dam and spillway. The existing earthen dam impounding Monument No. 1 Reservoir would be rebuilt and increased in size, expanding the water storage capacity of the facility from the current 570 acre-feet (AF) to 5,281 acre-feet. The current inundated area covers approximately 37 surface acres, which would be increased to about 160 acres following construction.

In order to accommodate construction vehicles and equipment, an administrative-use only road would be constructed over the existing Monument Trail (NFST 518) and would be widened, relocated and realigned, where needed, from its intersection with NFSR 262 to the new Monument No. 1 Reservoir dam site. About one-half mile of the road/trail at its start would be relocated to the north in order to avoid a cultural resource site. Relocating that portion of the route would result in road construction occurring in the Flattops/Elk Park Colorado Roadless Area.

The Forest Service would manage the realigned access route as a “coincidental road,” which would allow the designation of the route as both an administrative road and trail. As an administrative road, it would be gated and used for (1) operation and maintenance purposes necessary for the water right identified by Ute Water; (2) administrative purposes by the Forest Service; (3) fire; (4) emergency; or (5) law enforcement personnel. As NFST 518, it would remain open to the public as an ATV trail, open to vehicles less than 50 inches in width.

About 11/2 miles of the Monument Trail starting at the current dam would need to be relocated because the existing trail would be inundated by the water stored in the enlarged reservoir. The relocation would move the trail to higher ground along the northern shoreline of the newly-enlarged reservoir.

Approximately four miles of the Sunlight-Powderhorn (S-P) Snowmobile Trail would be relocated in order to avoid newly-inundated areas from the enlarged Monument No. 1 Reservoir. Instead of the trail following NFST 518 from NFSR 262, the trail would instead follow the East Leon Creek Trail (NFST 730) for about 11/2 miles and then go in an easterly direction to intersect the S-P Trail upstream of Monument No. 1 Reservoir. This trail is part of a popular 40-mile-long groomed trail system, and the new alignment would need to be about 22 feet wide in order to accommodate the groomer.

The existing dam is a homogeneous, gravelly clay embankment founded on glacial drift soils placed across Monument Creek, a tributary to East Leon Creek. It has a vertical height of 32 feet with a dam crest elevation at 10,206 feet, a crest width of 10 feet and crest length of about 500 feet. The proposed enlarged dam would increase the vertical height by 52 feet to a total of 85 feet with a dam crest elevation at 10,255 feet. The new crest width would be 25 feet and the crest length would be 1,850 feet.

The preliminary embankment design concept assumes a zoned earthen embankment with a 3:1 downstream slope and a 3.5:1 upstream slope. Six internal materials are associated with this type of dam construction. These materials include the upstream and downstream shells, a central clay core, sand chimney filter, gravel blanket drain, riprap and riprap bedding. A vertical tower positioned near the upstream toe would connect into a low level outlet works for use during normal operations and as a service spillway designed for storm events up to the 100-year interval. An emergency spillway would be located on the right abutment to convey storm events within the basin tributary to the reservoir greater than the 100-year storm event interval.

The soils beneath the enlarged embankment dam consist of deposits of glacial till overlying Uinta Formation siltstone, sandstone, and claystone. The proposed enlarged embankment would be constructed using material drawn from on-site borrow areas that would be ultimately inundated. The upstream slope of the dam would be surfaced with a layer of granular riprap bedding and riprap materials to protect against wave erosion. Riprap material, sourced from basaltic talus located throughout the reservoir, would be processed on-site.

A compacted clay core centrally located within the embankment would act as a barrier to seepage. The clay core would extend from the limits of foundation improvements (grout curtain) to the proposed normal water surface elevation of 10,250 feet above sea level (ASL). It is intended to minimize seepage, reduce pressure on the dam itself, and eliminate the soft soil conditions identified on the downstream toe of the embankment. The material necessary to construct the clay core exists within the reservoir footprint as identified during the Geotechnical Evaluation (URS, October 2011). A cutoff trench located beneath the clay core of the dam and consolidation grouting of this zone may be required.

The enlarged dam would have an internal drainage system to reduce pore pressures and to prevent internal erosion of embankment and foundation materials. The principal elements of the drainage system would include the filter and chimney drain immediately downstream of the clay core and the blanket drain constructed horizontally downstream of the central clay core along the footprint below the embankment shell. Toe drain collection piping would be constructed along the toe within the blanket drain to convey seepage safely through the embankment for monitoring and measurement. Materials necessary for construction of the internal drainage system are commercially available locally from the Grand Valley area and would need to be transported to the site.

The outlet works/service spillway tower would be constructed mainly of concrete, positioned near the upstream toe of embankment, and founded in strong, competent materials to prevent settlement. An access bridge would connect the tower to the dam crest for operation and maintenance equipment and personnel. The outlet works pipe would be sized as necessary to accommodate dam safety requirements for emergency drawdown or as necessary for the safe diversion of storm inflows during construction. The service spillway crest would establish the normal water surface elevation of the reservoir at 10,250 feet ASL and would pass excess water up to the 100-year storm event recurrence interval down the outlet works conduit into an energy-dissipating basin below the downstream toe of the dam.

The emergency spillway would be a new feature, located in a topographic saddle approximately 850 feet north of the right abutment. Releases from the emergency spillway in excess of the 100-year storm event would enter Monument Creek through an adjacent drainage approximately 500 feet downstream of the enlarged dam. Locating the uncontrolled releases from the emergency spillway away from the embankment is an important dam safety upgrade. The emergency spillway crest length and control sill elevation would be constructed based on the determination of the inflow design flood hydrology performed in accordance with the Colorado State Engineer's Dam Safety requirements.

Most of the materials for the construction would be derived, wherever possible, from the borrow areas and the nearby basaltic talus within the reservoir footprint to minimize haul distance, create additional reservoir storage, and minimize disturbed area. In addition, imported material necessary to construct the drainage collection system (crushed rock and sand), concrete materials including: aggregate, cement, and admixtures would be delivered for on-site batching from commercial locations. An estimated 40,000 cubic yards of sand, gravel, stone and other construction material would need to be imported for the dam enlargement, requiring an estimated 3,000 round trips using 25-ton end-dump haul trucks for an average of about eight round trips per day during the period of construction.

Because of the high site elevation and short construction season, construction of the dam enlargement and associated features could continue over three to four years. The first season would be used to improve access roads, develop borrow areas, stockpile embankment materials, import drainage materials, remove the existing dam, begin foundation grouting (if required), and establish the coffer dam, outlet works, and flood bypass structures. During the second year, construction of the outlet works/service spillway tower could be completed and embankment fill would begin. The third season would see the completion of the embankment, riprap placement, emergency spillway construction, and the access bridge to the tower.

All trees below 10,255 feet elevation surrounding the reservoir would need to be cleared prior to construction completion and reservoir filling. This work is necessary to reduce debris in the reservoir which could block spillway channels and impact reservoir operations.

About 40 acres of timber (predominantly spruce-fir) would be removed in order to accommodate the relocation of the Monument Trail (NFST 518), the S-P Snowmobile Trail and the enlarged inundated area for the reservoir.

Following construction of the new dam at Monument No. 1 Reservoir, the dam at Monument No. 2 Reservoir, which is located just northeast of Monument No. 1 Reservoir, would be breached, water control structures (outlet, concrete walls, etc.) would be removed and the area would be reseeded with native species. Additionally, willows would be transplanted from the impacted area of Monument No. 1 Reservoir.

The existing access route used for operation and maintenance of Monument No. 2 Reservoir would be rehabilitated to the extent necessary and closed to all uses. The water currently stored in that reservoir would be transferred to the newly-enlarged Monument No. 1 Reservoir. A wetlands mitigation plan to offset effects to wetlands caused by the enlargement of the Monument No. 1 Reservoir would be developed and would include the restoration of wetlands at Monument No. 2 Reservoir. Additional mitigation could be required by the Forest Service and/or U.S. Army Corps of Engineers.

A temporary workers' camp would be located near the construction site to reduce construction traffic and improve construction efficiency. The site would need to be large enough to accommodate six to ten camp trailers for the 15 to 20 workers and five to six trucks that would remain on-site. The camp could be located either at the reservoir site or on an old well pad near the intersection of NFSR 262 and NFST 518. Heavy equipment, including bulldozers, track hoes, road graders, and compactors would be stored near the construction site as work progresses. Temporary sanitary facilities and trash service would be maintained. A temporary special use permit would be required for the workers' camp.

As mitigation for effects to wetlands at Monument No. 1 Reservoir caused by the enlargement, Ute Water proposes to:

• Permanently drain Monument No. 2 Reservoir, remove the functioning dam, and transfer the water to Monument No. 1 Reservoir;
• Rehabilitate and permanently close the administrative access route to Monument No. 2 Reservoir;
• Reestablish or establish 19.37 acres of wetlands, including 3.18 acres of fen wetlands, within the drained basin of Monument No. 2 Reservoir. Work would include grading with excavators, roughening, and using seedling planting, transplants or seed plugs;
• Rehabilitate about 0.05-acre of wetlands just west of Monument No. 2 Reservoir degraded by the administrative access route; and
• Relinquish the Agriculture Irrigation and Livestock Watering System Easement issued by the Forest Service for Monument No. 2 Reservoir. Relinquishment of the easement removes a permanent encumbrance upon NFS lands.

Additional mitigation could be required by the Forest Service and/or U.S. Army Corps of Engineers.

Hunter Reservoir

The Hunter Reservoir Road (NFSR 280) intersects NFSR 262 and heads south along East Leon Creek to Hunter Reservoir and crosses streams in numerous locations. The current Forest Service RMO for NFSR 280 classifies the road as a high clearance, four-wheel drive road. Road improvements would include improving cross drainage by constructing rolling dips and lead-out ditches within and adjacent to the current road prism, removing extreme dips and bumps, adding rocks to perpetual soft areas of the road, and defining and hardening small stream crossings.

Approximately the last mile of the Hunter Reservoir Road (NFSR 280) would be relocated to eliminate current wetlands impacts in the creek bottom. This portion of the current road would be obliterated to the extent possible, as well as rehabilitating the wetlands in which the road currently lays. Signing by the Forest Service would be installed to direct the public and other users to the newly-relocated road.

The new road would leave the creek bottom and approach Hunter Reservoir in an upland location just west of East Leon Creek and go about 5,560 feet to the Hunter Reservoir dam. The road standard for this new route would be a Forest Service Traffic Service Level D, which includes a running surface ranging from 14 to 16 feet wide and an average corridor width, including the road, of 22 feet. The road would have native material surfaces with drainage structures and roadbed stabilization as shown on a plan and profile drawing. The design would show grades, structures, cross sections and alignments for the route, as well as estimated quantities of timber clearing acreage, seeding acreage, volumes of excavation, log deck locations, slash disposal areas, etc. Proposed road improvements and maintenance for the entire access route would be the responsibility of Ute Water during reservoir enlargement construction.

The new road would not be removed upon completion of the project but would remain in place and allowed to return to the specified high-clearance, four-wheel-drive condition and would be open to the public for use with full-sized vehicles, in accordance with the Grand Mesa Travel Plan. The final alignment of the relocated road would be approved in the field by the Forest Service prior to construction.

Because of the anticipated increase in traffic to Hunter Reservoir, commercial cattle guards would be installed and approximately one mile of fence relocated to the north at the junction of Leon Lake Road (NFSR 127), Hunter Reservoir Road (NFSR 280), and West Leon Trail (NFST 730). This would eliminate the need for two gates currently in place that need to be opened and closed by the public.

About a mile of the existing Leroux Creek Snowmobile Trail would be rerouted to avoid newly-inundated areas from the enlarged Hunter Reservoir. This trail is part of a groomed trail system, and the new alignment would need to be about 22 feet wide to accommodate the groomer.

The existing earthen dam impounding Hunter Reservoir would be rebuilt and increased in size, expanding the water storage capacity of the facility from the current 110 acre-feet to 1,340 acre-feet. The current inundated area covers approximately 19 surface acres, which would be increased to about 80 acres following construction.

The existing dam is a homogeneous, gravelly clay embankment founded on glacial drift soils placed across East Leon Creek. It has a vertical height of 11 feet with a crest elevation at 10,367 feet, a crest width of eight feet and crest length of 412 feet. The proposed enlarged dam would increase the vertical height by 26 feet to a total of 37 feet with a crest elevation at 10,393 feet. The new crest width would be 18 feet and the crest length would be 1,098 feet.

The new reservoir would require two saddle dams: The west saddle dam, an embankment located immediately west of the main dam, and the east saddle dam, located in a topographic saddle 600-700 feet east of the main dam. The saddle dams would have vertical heights less than 20 feet and crest lengths less than 570 feet (see Figure 2 below).

The soils beneath the enlarged embankment and the two saddle dams consist of glacial till overlying Uinta formation sandstone and claystone. The proposed saddle dams and enlarged embankments would be constructed using material drawn from on-site borrow areas that would ultimately be inundated. The upstream slope of the dam would be surfaced with a layer of riprap comprised of basalt boulders. The riprap would be taken from basaltic talus located just south of the reservoir and processed on-site. New outlet works would include replacement of the existing 18-inch outlet conduit with a 24-inch conduit.

A clay blanket cutoff, consisting of a 3-foot-deep layer of extremely clayey soil that acts as a barrier to seepage, would be located on the face of the dam upstream of the existing embankment. The cutoff would extend into the bedrock or to an elevation of 10,314 feet, whichever is reached first. It is intended to minimize seepage, reduce pressure on the dam itself, and eliminate the soft soil conditions identified on the downstream toe of the embankment.

The new dam would have two spillways, a replacement service spillway and a new emergency spillway. The new service spillway would control normal pool and pass routine floods downstream. Set in the west saddle dam, the spillway would establish normal pool at 10,388 feet elevation and would pass excess water down a conduit into an impact basin below the face of the dam. The emergency spillway would be a new feature, located in a topographic saddle about 1,600 feet southeast of the dam, with a concrete control beam at 10,389.5 feet elevation, 1.5 feet above normal pool. The emergency spillway is set away from the main embankment to discharge floodwater into a drainage basin just east of East Leon Creek, preventing erosion of the dam because of overtopping.

The enlarged dam embankment would have an internal drainage system to reduce pore pressures and to prevent internal erosion of embankment and foundation materials. The principal element of the drainage system would be toe drains in the embankment and the saddle dams to collect and convey seepage flows to the downstream side of the embankments. The toe drains would be 4-inch drainpipes surrounded by filter material.

Most materials for the construction would be derived from the borrow areas and the nearby basaltic talus described above. However, approximately 14,415 cubic yards (26,363 tons) of sand, gravel, stone and other construction material would need to be imported, requiring an estimated 1,056 round trips using 25-ton end-dump haul trucks for an average of about 8 round trips per day during the period of construction. Because of Hunter Reservoir's elevation and snow cover, the season during which construction activities could take place is short, extending from July until late September. The short construction season means that dam enlargement and construction of associated features would require three summers for completion.

A minimum conservation pool of 27 acre-feet at a maximum depth of 40 feet would be retained in the reservoir to maintain a viable fishery and to avoid winter kill, as proposed by Ute Water.

A conservation flow of 0.5 cfs or the amount of inflow into the reservoir would be released from October through May to preserve hydrologic function of the stream below the Hunter Reservoir dam. The exact dates in which the conservation flow would be required would fluctuate with the release schedule of the reservoir. At no time would the channel be allowed to be de-watered.

An on-site workers' camp would be established at Hunter Reservoir because of the time-consuming commute and the need to maximize working time at the site. The camp would be large enough to accommodate four to five camp trailers (approximately 500-600 square feet) for the ten to 15 workers and three to four trucks that would remain on site. Heavy equipment, including bulldozers, track hoes, road graders and a sheep's foot compactor, would be stored near the construction site as work progresses. Temporary sanitary facilities would be maintained on a weekly basis and trash would be contained in a metal bear-proof container. A temporary special use permit for the camp would be required.

Some of the proposed reservoir area to be inundated is forested. All trees below 10,393 feet elevation in areas that would be inundated would be cleared and the slash disposed of, per Forest Service instructions, prior to filling of the reservoir in order to reduce debris in the reservoir and the potential for blocking spillways. Construction of the new access road would also require the removal of trees. These activities would result in about nine acres of trees, mostly spruce-fir, being removed.

As mitigation for effects to wetlands at Hunter Reservoir caused by the enlargement, Ute Water proposes following actions:

• Relocation of the existing Hunter Reservoir Road out of the drainage bottom where it currently impacts wetlands and rehabilitating those wetlands following road relocation;
• Removal of existing embankment dams and water control structure at Jensen (aka Cold Sore) Reservoir, located in Sections 27 and 34, T. 11 S., R. 95 W., 6th P.M.;
• Transfer of Jensen Reservoir water rights held by Ute Water to another area, likely within the Cottonwood Creek watershed;
• Protection of approximately 8.3 acres of existing fen and rehabilitation of about 8.5 acres of degraded fen with the reservoir basin using techniques such as check dams, seed plugs, etc.;
• Removal of the existing two-track administrative route to the reservoir that crosses several wetland areas and serves access to perform operation and maintenance activities for Jensen Reservoir; and
• Relinquishment by Ute Water of the easement issued by the General Land Office pursuant to the Act of March 3, 1891, for Jensen Reservoir. This action eliminates a permanent encumbrance on National Forest System lands.

Additional mitigation could be required by the Forest Service and/or U.S. Army Corps of Engineers.

Possible Alternatives

Over 20 alternatives were initially considered (Scoping—DEIS, 2007), including some that would not involve use of NFS lands. Of those, the following alternatives have been identified for further analysis:

Alternative 1—Proposed Action: See Proposed Action description above.

Alternative 2—Big Park Reservoir: A new dam and reservoir would be constructed at a site located on Leon Creek in Section 5, T. 11 S., R. 93 W., 6th P.M., approximately 5.4 miles south of Vega Reservoir and 5 miles downstream from Hunter Reservoir at an elevation of about 9,400 ASL. A conditional water right for 5,650 acre-feet of water would be used to fill the new reservoir. The new earthen dam would have a height of 180 feet and a crest length of 2,100 feet, and surface area of the reservoir impounded behind the dam would be 123 acres at normal pool elevation.

A concrete diversion structure in Park Creek and a canal about 1.5 miles long would be constructed that would carry water south to the reservoir from the NE1/4 Section 32, R. 93 W., T. 10 S., 6th P.M. The canal would have an estimated capacity of 30 cfs. This would also require construction of new access road.

A service and emergency spillway, consisting of a 240-feet long concrete side channel and chute on the right abutment of the dam, would be constructed. A concrete hydraulic jump-type stilling basin would be used at the end of the spillway channel to dissipate the energy of the water and reduce the velocity of the water prior to it re-entering Leon Creek.

Approximately one-third mile of the NFSR 262 would be relocated to avoid inundated areas created by the new reservoir.

Approximately 85 acres of aspen and 46 acres of spruce-fir timber would be removed to allow for construction of the new dam, canal and relocated NFSR 262.

Some construction and fill material would be available onsite; however, approximately 526,600 cubic yards of clay core material, sand, and gravel would be imported. The availability of source rock for riprap is extremely limited at Big Park and, therefore, riprap would also need to be imported. With the use of 25-ton dump trucks, a total of about 21,000 round trips would be required to transport the necessary materials to the site.

The improvements for the rest of NFSR 262, including the transfer site, to the reservoir site would be the same as those described in the Proposed Action. A workers' camp would also be required.

Alternative 3—Reduced-Capacity Big Park Reservoir: A new dam and reservoir would be constructed at the same site as the Big Park Reservoir Alternative but of smaller scale and of greatly reduced capacity. The dam for this alternative would be 135-ft high with a 1,300-ft crest length, inundating approximately 52 acres, and providing 1,385 acre-feet of storage at normal pool elevation. Water rights from Park Creek would not be utilized under this alternative and, therefore, a feeder canal from Park Creek would not be required.

Construction access to the Reduced-Capacity Big Park dam site would be along NFSR 262, and the same road improvements described in the Proposed Action, including the transfer area, would be required to accommodate the heavy-truck traffic hauling fill material. Unlike the Big Park Reservoir, no relocation of NFSR 262 would be needed because the dam for the Reduced-Capacity Big Park Reservoir would be constructed farther west of NFSR 262 than the Big Park Reservoir. But that also means a longer access road would be needed to accommodate construction of the dam. It is anticipated that up to a mile of new road would be needed. After construction is completed, an access route to allow for operation and maintenance of the dam and stilling pond would remain. The permanent access route needed for operation and maintenance of the dam and reservoir would be narrowed to the minimum width necessary for this purpose and would be gated to prohibit public motorized access.

Some construction and fill material would be available onsite; however, about 167,000 cubic-yards of sand and gravel would be imported. Using 25-ton end-dump haul trucks, a total of over 15,000 round trips would be needed to transport the necessary embankment, riprap, and concrete raw materials to the site.

Approximately 56 acres of aspen and 23 acres of spruce-fir timber would be removed to allow for construction of the new dam and access route.

A workers' camp would also be necessary near the reservoir site during construction activities.

Alternative 4—No Action: Analysis of the No Action Alternative is required by 40 CFR part 1502.14(d). In the event the action alternatives were found to be unacceptable, this alternative could be selected. Under the No Action Alternative, the Forest Service would not permit the enlargement of Monument No. 1 or Hunter Reservoirs or the construction of any of the action alternatives that would occur on NFS lands. With no dam construction or enlargement occurring on NFS lands, there would be no need for new access road construction and road improvements associated with dam enlargement or construction; and no timber would be removed. The existing water developments and water resource conditions would continue. Under this alternative, Ute Water would still need to address dam safety concerns identified by the State Engineer's Office for the existing Hunter Reservoir. Ute Water's water rights, for which conditional decrees were issued, would not be developed. Ute Water may submit additional special use authorization applications for water improvements or developments on the GMUG for any of their water rights.

Lead and Cooperating Agencies

The Forest Service is the lead agency for preparation of the SDEIS. The U.S. Army Corps of Engineers (ACOE) and the Colorado Department of Natural Resources (DNR) are cooperating agencies.

Responsible Official

The responsible official for the Forest Service is the Forest Supervisor of the Grand Mesa, Uncompahgre and Gunnison National Forests. The responsible official for the ACOE is the Chief, Colorado West Regulatory Branch. The responsible official for the DNR is the Chief, Dam Safety Branch.

Nature of Decision To Be Made

Given the purpose and need, the Responsible Official for the Forest Service would review the Proposed Action, other alternatives and mitigation measures in order to make the following decisions:

• Whether or not to authorize the Proposed Action, road reconstruction and other support activities on National Forest System lands to meet the stated purpose by issuing:

(1) Special use permits pursuant to the Federal Land Policy and Management Act of October 21, 1976, as amended (FLPMA), for each of the reservoir enlargements;

(2) Temporary special use permits pursuant to the Act of June 4, 1897, for on-site workers' camps;

(3) Mineral materials contracts for borrow material and riprap (The Materials Act of July 31, 1947);

(4) Road use permits for the necessary road reconstruction and relocation (National Forest Roads and Trails Act of October 13, 1964 (FRTA)); and

(5) Timber contracts for the removal of timber that would otherwise be inundated following enlargement of the reservoirs (Timber Settlement Authority (36 CFR 223.12)).

• If an alternative is selected on National Forest System lands, under what conditions and by which methods implementation of the alternative and associated activities would be conducted.
• Whether or not the proposed mitigation is appropriate to offset impacts to resources as a result of implementation of alternatives.

The Responsible Official for the Army Corps of Engineers will determine whether or not to issue a permit in accordance with Section 404(b)(1) of the Clean Water Act and whether or not the mitigation proposed for wetlands impacts at Monument No. 1 and Hunter Reservoirs, as outlined in a wetlands mitigation plan, is adequate.

The Responsible Office for the Colorado Department of Natural Resources will review and approve the conceptual dam designs prior to construction. As-built plans must be approved by the DNR following construction but prior to water being stored in the reservoirs.

Preliminary Issues

Soils: Dam reconstruction could directly impact areas of soil within the landscape where construction activities would be occurring. The soil in those areas could be altered by heavy equipment, affecting densities, infiltration rates, natural horizonation and overall productivity. These disturbed areas could experience erosion until they are stabilized.

Water Resources: The change in water storage and water management could affect the base flow and peak flow conditions below Monument No. 1 Reservoir and Hunter Reservoir. Dam reconstruction, road grading and leveling and placement of stream crossings by access roads could produce temporary increases in sedimentation and erosion downstream in Leon and Monument Creeks.

Wetlands: Year-round or seasonal inundation of wetlands, including fens, located at Monument No. 1 and Hunter Reservoirs, could diminish or disrupt the wetland function.

Wildlife (including Aquatic Wildlife): Sedimentation resulting from dam reconstruction and road construction, use and maintenance could reduce water quality and affect fish populations and aquatic habitat. Operation and maintenance of the reconstructed dams and enlarged reservoirs could affect fisheries downstream and the aquatic environment by altering stream flow patterns and by changing the water temperature.

Special Status Species (Threatened/Endangered/Sensitive/MIS): Reconstruction and operation and maintenance of the dams and enlarged reservoirs could affect fish and wildlife habitat of special status species, such as federally listed and Forest Service sensitive species.

Recreation and Transportation: Project activities could remove dispersed campsites during and after dam reconstruction.

Project construction activities could make NFSRs 262 and 280 and NFST 518 temporarily inaccessible. Temporary improved access could temporarily change the recreational opportunity spectrum classification in the area of Monument No. 1 and Hunter Reservoirs. Temporary improved access to the reservoirs could cause the expectation and desire on the part of the public for continued improved access.

Colorado Roadless Areas: Enlargement of the Monument No. 1 and Hunter Reservoirs would add municipal water supply storage within the Flattops/Elk Park Colorado Roadless Area (CRA) consistent with valid exisiting rights. Although the access routes to Hunter Reservoir and the majority of the access route to Monument No. 1 Reservoir are outside the CRA boundary, the current NFST 518 starts in the CRA. Under the Proposed Action, the access route would be widened, upgraded and relocated in order to avoid a cultural site; and that construction would be done within the CRA.

Permits or Licenses Required

Forest Service: Includes, but is not limited to, FLPMA special use permits, temporary special use permits (workers' camp, etc.), road use permits, mineral material permits, and timber removal contracts.

U.S. Army Corps of Engineers: Department of the Army permit pursuant to Section 404(b)(1) of the Clean Water Act.

Colorado Water Quality Control Division: Water quality certification under Section 401 of the Clean Water Act.

Scoping Process

This notice of intent continues the scoping process, which guides the development of the SDEIS. Comments received in response to the DEIS will also be addressed in the SDEIS.

It is important that reviewers provide their comments at such times and in such manner that they are useful to the agency's preparation of the environmental impact statement. Therefore, comments should be provided prior to the close of the comment period and should clearly articulate the reviewer's concerns and contentions related to the expanded scope of the analysis.

Comments received in response to this solicitation, including names and addresses of those who comment, will be part of the public record for this proposed action. Comments submitted anonymously will be accepted and considered, however.