Telephone Flat Geothermal Development Project Final EIS/EIR

3.10.3.4 Alternative Power Plant Site A

The proposed operations and facilities for the Alternative Power Plant Site A would be similar to the Proposed Action except that the Alternative Power Plant Site A electrical generation facilities would be located approximately ¼-mile east of the proposed power plant site. Small changes in well pad locations, access roads, and pipeline routing would be required, but generally most wellfield facilities would be consistent with those described for the Proposed Action.

3.10.3.4.1 Environmental Consequences of Alternative Power Plant Site A

Alternative Site A would have similar recreational impacts as the Proposed Action. Although the power plant would be approximately ¼-mile east of the power plant location identified for the Proposed Action, the amount of roadway improvement would generally be the same (same impact to snowmobile trails); and the amount of geothermal pipeline would generally be the same (same level of potential hazard to snowmobilers). The following impacts, statements of significance and mitigation measures are similar to those identified for the Proposed Action. The full discussion of adverse effects described for the Proposed Action is also applicable to Project Alternative Power Plant Site A.

Impact 3.10.3.4-1: The Project would result in sights, sounds or odors that would collectively detract from the Forest visitor’s recreational experience. Existing dispersed recreational uses allowed in the area of the Proposed Action consist of motorized vehicles of different types (off-highway, water, and snow vehicles) with the associated noise and air emissions. Developed recreational uses also allow for trailer camping and power boating. Intrusional impacts ( i.e., visual, noise and air quality effects) associated with the construction phase are individually addressed in other sections of this document. There is no practical way to measure the collective intrusional impact from the Project on recreation in the Project vicinity.

Significance of the Impact: This impact is considered to be below the level of significance and no mitigation measures are required. Measures to reduce the adverse effects of the Project on individual environmental resources (i.e., air quality, noise, visual, and transportation resources) are discussed in Sections 3.4, 3.7, 3.8, and 3.11 of this EIS/EIR, respectively.

Impact 3.10.3.4-2: Snowplowing Project access roads will eliminate or damage sections of designated groomed snowmobile trails which align with Primary Forest Route 97 and Forest Roads 43N53 and 43N21. The Project would plow an area near the junction of Primary Forest Route 97 and 43N53 for public winter parking which would provide a potential access benefit to snowmobile users.

Significance of the Impact: Despite the improved winter access to the Medicine Lake Highlands and increased parking that would be provided by the Project, this impact is considered potentially significant. The following mitigation measures are provided which would reduce the adverse effects of the Project to below the level of significance.

Mitigation Measure 3.10.3.4-2a: The Project Applicant shall make space available adjacent, or reasonably parallel, to snowplowed access roads to allow grooming and continuing use of existing designated snowmobile trails in the Project area. Snowmobile crossings of snowplowed access roads shall be clearly marked both along the snowmobile trail and the snowplowed access road warning of the crossing.

Mitigation Measure 3.10.3.4-2b: The Project Applicant shall make available emergency first aid assistance at the power plant to snowmobilers. The emergency assistance made available shall include telecommunications for retrieval by ambulance service or other emergency transport. One or more employees on site during winter operations shall be trained in emergency first aid for injuries typically associated with snowmobiling accidents and exposure to cold weather. Signs from the snowmobile trail to the power plant site shall be posted over the seasonal period when snowmobiling is conducted in the vicinity of the Project.

Impact 3.10.3.4-3: The temperature of the geothermal fluid at the wellhead is expected to exceed 330 F. The geothermal pipelines would be insulated with 3-inches of insulation wrapped in sheet metal which is expected to substantially limit heat loss from the pipelines, and the external surface of the insulated geothermal pipelines is expected to be comfortable to the touch. However, there is concern that heat from the geothermal fluid in the pipelines could melt the snow above the pipeline resulting in trenches, creating areas of softer snow, or exposing pipeline obstacles that could pose a safety hazard to snowmobile riders.

Significance of the Impact: The effect of geothermal pipelines on snow cover under all potential conditions which may be experienced in the Project area is uncertain. This impact is considered potentially significant. The following mitigation measures are provided to reduce the adverse effects of this impact to below the level of significance.

Mitigation Measure 3.10.3.4-3a: Poles and warning signs marking the location of geothermal pipelines, visible above accumulated snow levels, shall be placed on or adjacent to those geothermal pipelines which parallel or cross snowmobile trails.

Mitigation Measure 3.10.3.4-3b: Geothermal pipeline corridors which cross access roads in the Project area, and which seasonally are used as existing designated snowmobile trails, shall be routed below ground within bridge/culvert road crossings.

3.10.3.4.2 Unavoidable Adverse Effects of Alternative Power Plant Site A

Alternative Site A would have unavoidable adverse effects similar to the Proposed Action. Both developed recreation near Medicine Lake and dispersed recreational uses of the Forest in the immediate vicinity of the wellfield and power plant site would be periodically affected by the collective intrusional impacts of the Project. Designated snowmobile trails which align with Project access roads would be affected by snowplowing and Project facilities.

3.10.3.5 Alternative Power Plant Site B

The proposed operations and facilities for the Alternative Power Plant Site B would be similar to the Proposed Action except that the Alternative Power Plant Site B electrical generation facilities would be located approximately ½-mile east of the proposed power plant site. Changes in well pad locations, access roads, and pipeline routing would be required. A new access road would be required to extend from Primary Forest Route 97 to new well pad 77-18.

3.10.3.5.1 Environmental Consequences of Alternative Power Plant Site B

Alternative Power Plant Site B would have similar recreational impacts as the Proposed Action. Although the power plant would be approximately ½-mile east of the power plant location identified for the Proposed Action, the amount of roadway improvement would generally be the same except for approximately 1,200 feet of new access road extending from Primary Forest Route 97 to new well pad 77-18. This new access road would require another crossing of Primary Forest Route 97 and would result in added potential damage to snowmobile groomed trails. The following impacts, statements of significance and mitigation measures are similar to those identified for the Proposed Action. The full discussion of adverse effects described for the Proposed Action is also applicable to Project Alternative Power Plant Site B.

Impact 3.10.3.5-1: The Project would result in sights, sounds or odors that would collectively detract from the Forest visitor’s recreational experience. Existing dispersed recreational uses allowed in the area of the Proposed Action consist of motorized vehicles of different types (off-highway, water, and snow vehicles) with the associated noise and air emissions. Developed recreational uses also allow for trailer camping and power boating. Intrusional impacts ( i.e., visual, noise and air quality effects) associated with the construction phase are individually addressed in other sections of this document. There is no practical way to measure the collective intrusional impact from the Project on recreation in the Project vicinity.

Impact 3.10.3.5-2: Snowplowing Project access roads will eliminate or damage sections of designated groomed snowmobile trails which align with Primary Forest Route 97 and Forest Roads 43N53 and 43N21. The Project would plow an area near the junction of Primary Forest Route 97 and 43N53 for public winter parking which would provide a potential access benefit to snowmobile users. The extent of effect on designated groomed snowmobile trails is expected to be greater than for the Project or Alternative Site A due to the additional crossing of Primary Forest Route 97 to access well pad 77-18.

Mitigation Measure 3.10.3.5-2a: The Project Applicant shall make space available adjacent, or reasonably parallel, to snowplowed access roads to allow grooming and continuing use of existing designated snowmobile trails in the Project area. Snowmobile crossings of snowplowed access roads shall be clearly marked both along the snowmobile trail and the snowplowed access road warning of the crossing.

Mitigation Measure 3.10.3.5-2b: The Project Applicant shall make available emergency first aid assistance at the power plant to snowmobilers. The emergency assistance made available shall include telecommunications for retrieval by ambulance service or other emergency transport. One or more employees on site during winter operations shall be trained in emergency first aid for injuries typically associated with snowmobiling accidents and exposure to cold weather. Signs from the snowmobile trail to the power plant site shall be posted over the seasonal period when snowmobiling is conducted in the vicinity of the Project.

Impact 3.10.3.5-3: The temperature of the geothermal fluid at the wellhead is expected to exceed 330 F. The geothermal pipelines would be insulated with 3-inches of insulation wrapped in sheet metal which is expected to substantially limit heat loss from the pipelines, and the external surface of the insulated geothermal pipelines is expected to be comfortable to the touch. However, there is concern that heat from the geothermal fluid in the pipelines could melt the snow above the pipeline resulting in trenches, creating areas of softer snow, or exposing pipeline obstacles that could pose a safety hazard to snowmobile riders.

Mitigation Measure 3.10.3.5-3a: Poles and warning signs marking the location of geothermal pipelines, visible above accumulated snow levels, shall be placed on or adjacent to those geothermal pipelines which parallel or cross snowmobile trails.

Mitigation Measure 3.10.3.5-3b: Geothermal pipeline corridors which cross access roads in the Project area, and which seasonally are used as existing designated snowmobile trails, shall be routed below ground within bridge/culvert road crossings.

3.10.3.5.2 Unavoidable Adverse Effects of Alternative Site B

Alternative Power Plant Site B would have unavoidable adverse effects that are expected to be slightly greater than the Proposed Action or Alternative Power Plant Site A. Both developed recreation near Medicine Lake and dispersed recreational uses of the Forest in the immediate vicinity of the wellfield and power plant site would be periodically affected by the collective intrusional impacts of the Project. Designated snowmobile trails which align with Project access roads would be affected to a slightly greater degree due to increased damage to snowmobile groomed trails, and Project facilities.

3.10.3.6 Alternative Transmission Line Routes

Previous Transmission Line Impact Assessment:

As discussed in Section 2.2.5, the transmission line originating at the Telephone Flat Project power plant site would be routed to interconnect with a transmission line located within one of the six alternative utility corridors evaluated in the Fourmile Hill Project EIS/EIR to be selected by the agencies as the preferred utility corridor between the Medicine Lake Highlands and the existing BPA Malin-Warner transmission line (BLM et al. 1998). The Fourmile Hill Project EIS/EIR evaluated seven different possible line segments (segments A1, A2, A3, B1, B2, C1 and C2) which could be used in different combinations to comprise the preferred utility corridor. Only five of these line segments (A2, B1, B2, C1 and C2) could possibly be used by the Telephone Flat Project, and the Land Use and Recreation analysis from the Fourmile Hill Project EIS/EIR of the five line segments which could be potentially used by the Telephone Flat Project are incorporated by reference into this EIS/EIR (see pages 3-162 through 3-179, and 4-190 through 4-209 of the Fourmile Hill Project EIS/EIR; BLM et al. 1998). The findings of the earlier assessment are also summarized in Exhibit 4 of this EIS/EIR (See Table S-5, pages S-30 to S-36, provided in Exhibit 4).

Telephone Flat Project Route Alternatives:

If the agencies select one of the Fourmile Hill Project utility corridor alternatives which route through the Medicine Lake basin in close proximity to the Telephone Flat Project (i.e., Alternatives 1 through 4), then the Telephone Flat Project would construct either line segment D1 (if Alternatives 1 or 2 is selected) or line segment D2 (if Alternatives 3 or 4 is selected), and no specific agency decision on transmission line route alternatives would need to be made for the Telephone Flat Project. However, if the Northern Utility Corridor for the Fourmile Hill Project (i.e., Alternatives 5 or 6) is selected as the agency-preferred utility corridor, then a second decision for the Telephone Flat Project would need to be made with respect to how to interconnect the Telephone Flat Project transmission line with the Northern Utility Corridor. Two alternative Telephone Flat Project transmission line routes (Route 1 and Route 2) are being considered for transporting power generated from the Telephone Flat Project power plant site to the Northern Utility Corridor.

3.10.3.6.1 Environmental Consequences of Route 1 (Line Segments D1 + A2)

Line Segment D1:

Line segment D1 is located entirely within the Project wellfield area, and the effects for line segment D1 would be the same as those described for the Proposed Action.

Line Segment A2:

The recreational consequences of constructing, operating and decommissioning transmission line segment A2 have been documented in a prior environmental document (BLM et al. 1998). According to the Fourmile Hill Geothermal Project EIS/EIR, transmission line segment A2 would pass through the portion of the Mount Hoffman Released Roadless Area that has an ROS designation of Roaded Natural. Segment A2 of the proposed Route 1 would then skirt the northwest margin of the Glass Mountain Geologic Area which has an ROS designation of Semi-Primitive Wilderness (see Figure 3.10.2). Approximately two miles east of Mount Hoffman, the transmission line would pass through a gap in the geologic area, which has an ROS of Roaded Natural. Construction of the transmission line in this area would thus be consistent with the ROS designation of Roaded Natural, which allows for road construction and conventional motorized uses.

Impact 3.10.3.6.1-1 (Fourmile Hill Impact described in Section 4.11.5): Line segment A2 would have an adverse effect on dispersed recreation as it would pass through a portion of the Mt. Hoffman Released Roadless Area. Project operations would have similar impacts on dispersed recreation as those identified for construction. During dismantling and decommissioning of project facilities, similar impacts on dispersed recreation would occur as described for construction. However, once complete, project decommissioning would eliminate the adverse effects of the transmission line by removing all facilities and eliminating winter access road plowing.

Significance of the Impact: Although the presence of the transmission line in the Mt. Hoffman Released Roadless Area could represent a greater contrast with the surrounding forested landscape than in other dispersed recreation area locations on the forest, the presence of the transmission line would occupy a relatively small portion of the released roadless area, and the construction activities would occur on a temporary basis. Any recreational user that is bothered or annoyed by the transmission line can readily move out of the vicinity or make a decision not to recreate in proximity to the transmission line. This impact is below the level of significance and does not require mitigation.

Impact 3.10.3.6.1-2 (Similar to Fourmile Hill Impact described in Section 4.11.4): Line segment A2 would have a beneficial recreational effect as it would result in right-of-way vegetation clearance along the transmission line route and along transmission line access roads. Portions of these routes would be accessible to recreationalists and would benefit dispersed recreation by providing mountain biking, horseback riding, and hiking touring routes. Project operations would have similar impacts on dispersed recreation as those identified for construction. During dismantling and decommissioning of project facilities, similar impacts on dispersed recreation would occur as described for construction. However, once complete, project decommissioning would eliminate the beneficial effects of increased recreational access along the proposed transmission line right-of-way and associated access roads.

Significance of the Impact: This effect is beneficial and does not require mitigation.

3.10.3.6.2 Environmental Consequences of Route 2 (Line Segments D2 + B2*) Line Segment D2:

Line segment D2 is located entirely within the Project wellfield area, and the effects for line segment D2 would be the same as those described for the Proposed Action.

Line Segment B2:

The recreational consequences of constructing, operating and decommissioning transmission line segment B2 have been documented in a prior environmental document (BLM et al. 1998). The use of transmission line segment B2 would eliminate construction of transmission line A2 through the Mount Hoffman Released Roadless Area. No Alternative-specific adverse effects on recreation were identified for Route 2.

Impact 3.10.3.6.2-1 (Similar to Fourmile Hill Impact described in Section 4.11.4): Line segment A2 would have a beneficial recreational effect as it would result in right-of-way vegetation clearance along the transmission line route and along transmission line access roads. Portions of these routes would be accessible to recreationalists and would benefit dispersed recreation by providing mountain biking, horseback riding, and hiking touring routes. Project operations would have similar impacts on dispersed recreation as those identified for construction. During dismantling and decommissioning of project facilities, similar impacts on dispersed recreation would occur as described for construction. However, once complete, project decommissioning would eliminate the beneficial effects of increased recreational access along the proposed transmission line right-of-way and associated access roads.

Significance of the Impact: This effect is beneficial and does not require mitigation.

3.10.3.6.3 Unavoidable Adverse Impacts of Alternative Transmission Line Routes

Dispersed recreational use opportunities in areas adjacent to either of the Alternative Transmission Line Routes 1 and 2 would be slightly reduced, particularly during construction and decommissioning phases.

3.10.3.7 No Action Alternative

The No Action Alternative would not implement the proposed Telephone Flat Geothermal Development Project.

3.10.3.7.1 Environmental Consequences of No Action Alternative

The recreational impacts from implementation of the Project would not occur. There would be no adverse recreational consequences associated with the No Action Alternative.

3.10.3.7.2 Unavoidable Adverse Impacts of the No Action Alternative

There would be no unavoidable adverse recreational impacts associated with the No Action Alternative.

Telephone Flat Geothermal Development Project Final EIS/EIR