e) Discussion
The Final EIR/EIS concludes that the Alligator Rock-North of Desert Center route segment is environmentally preferred because it would minimize biological, cultural, and wilderness area impacts, even though it would be closer to populated areas and would require two crossings of I-10.
SCE favors placing DPV2 adjacent to DPV1 through the Alligator Rock ACEC. SCE states that it has good information on the site features associated with Alligator Rock and believes that all significant features can be avoided with careful construction monitoring. SCE states that no comparable information exists for the North of Desert Center alternative, and that SCE has not surveyed the North of Desert Center route and has not acquired right of way for the route. SCE notes that, in any event, BLM must grant a permit for the DPV2 route in the Alligator Rock area, since all alternatives lie wholly or partially on BLM lands.
Because the Alligator Rock-North of Desert Center alternative, which crosses both BLM and private land, is the environmentally preferred alternative, SCE should construct the North of Desert Center alternative if BLM authorizes this route in its Record of Decision. It is reasonable to grant SCE the flexibility, if BLM does not authorize the Alligator Rock-North of Desert Center route segment, to build DPV2 on a route segment through the Alligator Rock ACEC that is authorized by BLM, if the segment received full consideration in the Final EIR/EIS, or if it deviates from one of the reviewed route segments solely within BLM land and BLM undertakes the environmental review needed under NEPA.
5. Desert Southwest Transmission Project and Midpoint Substation
The Desert Southwest transmission project proposed by IID would include a 118-mile 500 kV transmission line generally paralleling DPV1 and DPV2 between Blythe and SCE's Devers substation.
The Desert Southwest project would originate at a new Keim substation near the Blythe Energy Project power plant. Either a double-circuit 500 kV line or two parallel 500 kV lines would be constructed from the Keim substation to a new Midpoint substation to be located where the line(s) intersect the existing DPV1 line. The Desert Southwest route from the Midpoint substation to Devers generally would be parallel to and immediately north of SCE's right of way for DPV1 and DPV2. It would diverge from the DPV1 corridor only in the vicinity of the Alligator Rock ACEC, as described above in the Alligator Rock-South of I-10 alternative.
IID and BLM prepared a joint EIR/EIS regarding the Desert Southwest project. On September 15, 2006, BLM issued a Record of Decision allowing IID a right of way to use public lands to construct the Desert Southwest project, with the portion between the Blythe area and the Devers substation as a separate stand-alone transmission line adjacent to the DPV2 right of way. In its Record of Decision regarding the Desert Southwest project, BLM approved the Desert Southwest route that IID proposed in the vicinity of Alligator Rock, described in Section IV.A.4.d above. The Desert Southwest EIR/EIS did not consider an alternative north of I-10 in the vicinity of Alligator Rock comparable to the North of Desert Center alternative that the Final EIR/EIS for DPV2 found environmentally superior.
The Final EIR/EIS evaluates the Desert Southwest transmission project as a potential alternative to the portion of DPV2 between a new Midpoint substation and Devers. In this scenario, the Midpoint-to-Devers portion of the Desert Southwest project would carry up to 1,200 MW of load from the Blythe Energy Project and Arizona. The Final EIR/EIS also considers separately the cumulative environmental impacts if both DPV2 and the Desert Southwest project are built as separate 500 kV transmission lines.
Overall, the environmental impacts of the Desert Southwest project as an alternative to DPV2 would be very similar to those of the comparable portion of the proposed DPV2 project with the Alligator Rock-South of I-10 alternative. The Final EIR/EIS concludes that the proposed DPV2 project is environmentally preferred over the Desert Southwest project because it would require less ground disturbance and construction of fewer substations.
b) Possible Integration of DPV2 and Desert Southwest Transmission Projects
SCE and IID are in discussions to integrate the DPV2 and Desert Southwest transmission projects, so that only one 500 kV line would be constructed between a new Midpoint substation and Devers. SCE states that, if SCE and IID reach agreement, the cost to SCE would not exceed the cost of a stand-alone project and DPV2's cost-effectiveness would not be affected adversely. The transfer capability of DPV2 would be expanded from 1,200 MW to 2,340 MW, probably through upgrading series capacitors on the line. SCE would still turn over 1,200 MW of transfer capability to the CAISO, as SCE has proposed in A.05-04-015, and the remainder of the transfer capability would be managed by IID.
SCE describes that, if a joint DPV2-Desert Southwest project arrangement is reached with IID, the joint project arrangement would be a FERC-jurisdictional contract. SCE states that it would file a Permit to Construct application for the new Midpoint substation, as required by GO 131-D. SCE believes that the analysis in the joint EIR/EIS for the Desert Southwest project prepared by BLM and IID satisfies California's environmental requirements for the new substation, so that there would be no need to conduct any additional environmental review.
Neither SCE's PEA nor the Final EIR/EIS for DPV2 addressed environmental impacts that would occur if DPV2 were integrated with the Desert Southwest project with system upgrades that would increase the transfer capability of DPV2 above 1,200 MW. We view possible integration of DPV2 and the Desert Southwest project as speculative at this time, and find that the Final EIR/EIS addressed the Desert Southwest project adequately. However, we note that an increase in the transfer capability of DPV2 may have impacts such as increases in corona noise and EMF that were not addressed in the Final EIR/EIS. We do not authorize SCE to construct the Midpoint substation at this time. If SCE and IID reach agreement regarding integration of DPV2 and the Desert Southwest transmission project, SCE must address environmental and other impacts of the proposed upgrade to DPV2 in any filing requesting Commission authorization to construct the Midpoint substation.
B. Transmission Upgrades West of Devers Substation
The "West of Devers" portion of the proposed DPV2 project would include upgrades to approximately 48 miles of 230 kV transmission lines west of the Devers substation. SCE would replace two existing 230 kV lines with a new double-circuit 230 kV line and would reconductor a third 230 kV line between the Devers substation and the San Bernardino Junction at the western end of San Timoteo Canyon. SCE would also reconductor a 230 kV transmission line between San Bernardino Junction and the Vista substation, and a 230 kV transmission line between San Bernardino Junction and the San Bernardino substation. SCE also proposes to install Special Protection Scheme relays at the Devers substation, the Padua substation in San Bernardino County, and the Vista substation in Riverside County.
The Final EIR/EIS concludes that the proposed 230 kV upgrades would have significant unmitigable impacts on cultural resources and air quality, which we discuss in Section IV.C as general impacts of the DPV2 project. At the same time, the proposed replacement of two existing 230 kV lines with a single double-circuit 230 kV line would improve views at viewpoints including Cedar Hollow Road in the City of Beaumont, Stargazer Street and Rose Avenue in the City of Beaumont, and the Oak Valley Golf Course in the City of Beaumont. Noise levels along the 230 kV lines would decrease because of the increased capacities of the new conductors and the reconfiguration of towers.
Some of the existing 230 kV transmission lines west of Devers that SCE proposes to upgrade cross over lands of the Morongo Band of Mission Indians (Morango Tribe) pursuant to existing right-of-way agreements that expire beginning in 2010. SCE reports that the Morango Tribe has informed SCE that continued use of the existing 230 kV transmission corridor after the current right-of-way agreements expire is not acceptable, but that the Morango Tribe is willing to negotiate regarding a new right-of-way corridor some distance from the existing 230 kV transmission lines. SCE expects that this new transmission corridor would cross less of the reservation and more privately-owned land.
Because of the Morango Tribe's opposition to the 230 kV upgrades over its land, SCE concludes that such upgrades are not feasible. SCE now recommends that the Commission authorize construction of the Devers-Valley No. 2 alternative.
The Final EIR/EIS evaluates the Devers-Valley No. 2 alternative, a new 41.6-mile 500 kV line that would be constructed immediately adjacent to SCE's existing Devers-Valley No. 1's 500 kV transmission line, and primarily within existing easements. The route is adjacent to residential areas in the City of Banning and also in unincorporated portions of Riverside County including the Cabazon Estates area and the communities of Juniper Flat and Romoland. The route would traverse 4.7 miles of the Santa Rosa and San Jacinto Mountains National Monument (administered by BLM), approximately 1.9 miles of the San Bernardino National Forest, and the Potrero ACEC. It would cross the Pacific Crest National Scenic Trail, and the towers would be visible from the San Jacinto Wilderness Area.
Before the Devers-Valley No. 2 transmission line could be constructed, the Forest Service in the United States Department of Agriculture would have to determine whether it would be consistent with management direction in the governing Forest Plan. Based on Forest Service and BLM determinations, this alternative could require amendments to the San Bernardino National Forest Land Management Plan, the National Monument Proposed Management Plan, and an existing memorandum of understanding among BLM, the Forest Service, and the Pacific Crest Trail Association.
The Final EIR/EIS finds that the Devers-Valley No. 2 alternative would have significant unmitigable visual impacts because of the increased structural contrast, skylining, and view blockage along the corridor, and also from nearby areas including State Route 243, Mapes Road, and the community of Beaumont. The new transmission towers would increase significantly the amount of industrial development and diminish significantly the character and recreational value of the traversed and adjacent recreational resources. The Final EIR/EIS concludes that impacts to the Santa Rosa and San Jacinto National Monument, the Pacific Coast Trail, the San Bernardino National Forest, the San Jacinto Wilderness Area, and the Potrero ACEC would be significant and unmitigable.
The Final EIR/EIS states that the West of Devers 230 kV upgrades are environmentally preferred over the Devers-Valley No. 2 alternative but that the Devers-Valley No. 2 alternative would be feasible to construct. The Final EIR/EIS concludes that, if the proposed West of Devers upgrades are found to be infeasible, the Devers-Valley No. 2 alternative would meet project objectives and would allow the entire DPV2 project to be constructed.
Because the Morango Tribe has informed SCE that the proposed upgrades to SCE's existing 230 kV transmission lines west of Devers are not acceptable, we agree with SCE that the West of Devers portion of SCE's proposed DPV2 project is not feasible. While it appears that the Morango Tribe may be amenable to an alternative transmission corridor across its land, such an alternative route has not been identified at this time. We do not know how long negotiations could take or, if SCE were to reach agreement with the Morango Tribe, whether the agreed-upon transmission corridor over tribal land would be found acceptable after subsequent environmental review.
It is reasonable to authorize construction of the Devers-Valley No. 2 alternative. This would allow completion of the economically advantageous DPV2 project within the schedule proposed by SCE. With anticipated continued load growth in southern California, additional transmission upgrades west of Devers may be needed in the future. With authorization of the Devers-Valley No. 2 route, SCE and the Morango Tribe may continue to negotiate a new right-of-way agreement independent of DPV2.
C. General Environmental Impacts
The Final EIR/EIS identifies several known archaeological sites eligible for listing on the National Register of Historic Places (National Register) that could be affected by DPV2 construction and operation, with additional potentially eligible cultural resource sites located within or adjacent to the transmission corridor. The Final EIR/EIS notes that some areas of direct impact, such as roads and temporary laydown areas, have not been specified or surveyed and that adverse effects to individual sites cannot be identified precisely until final tower locations are determined, detailed engineering plans for all project roads and facilities are completed, and final eligibility of cultural resources for the National Register has been assessed. Also, there is potential to encounter undiscovered cultural and paleontological resources, as well as buried Native American human remains. The Final EIR/EIS proposes several mitigation measures that would allow many direct impacts to be avoided through minor design modifications. The Final EIR/EIS concludes, however, that significant impacts may be unavoidable during project construction or operation.
The Final EIR/EIS reports that addition of a second 500 kV line in the DPV1 and Devers-Valley No. 1 corridors would increase permanent noise levels and that the increased noise would create a significant and unmitigable impact at times along portions of the right of way. Specifically, the Final EIR/EIS finds that corona noise levels during wet weather and heavy line loads would violate Riverside County noise policies for residential and other noise-sensitive land uses within 25 feet of the 500 kV right of way.15 SCE disputes this finding and asserts that it should not be required to mitigate DPV2's noise impacts.
Riverside County Noise Element Policy N.1.1 specifies that residential and other noise-sensitive land uses should be protected from high levels of noise by restricting or relocating noise sources, and Policy N.1.3 establishes a 65 CNEL16 level as the appropriate trigger level for mitigation. The Final EIR/EIS describes that corona noise levels during wet weather and heavy line loads along the proposed Devers-Harquahala segment would increase to about 65.7 Ldn17 at the edge of the right of way. It concludes that the Riverside County noise policy would be violated during those times for residential uses within 25 feet of the right of way. While noise studies were not provided for the Devers-Valley alternate route, the Final EIR/EIS concludes that the Riverside County noise policy would likely be violated similarly during wet weather and heavy load conditions along the Devers-Valley corridor.
The Final EIR/EIS identifies that the proposed Devers-Harquahala 500 kV line would be located approximately 100 feet from two or three residences in the Palo Verde Valley west of Blythe in California and also would be adjacent to residences in the communities of Thousand Palms and North Palm Springs. The Devers-Valley 500 kV route is adjacent to residential areas in the City of Banning and in unincorporated portions of Riverside County including the Cabazon Estates area, the community of Juniper Flats, areas south of Banning, and areas near the community of Romoland. The Final EIR/EIS did not identify any structures within 25 feet of the right of way, but the identified noise impacts are presumed to occur in the outdoor areas of the residential properties.
SCE contests the finding in the Final EIR/EIS that the DPV2 corona noise level would conflict with the Riverside County noise ordinance. SCE states that the method relied upon in the draft EIR/EIS is based on the L5 noise level (the volume of sound exceeded 5% of the time). SCE reports that, for recent utility projects, Riverside County has applied the CNEL process based on the L50 noise level (the volume of sound exceeded 50% of the time) rather than the L5 noise level. SCE submits that use of the DPV2 project's L50 noise level of 54.7 dBA results in a CNEL noise level of 61.4 dBA, below the 65 dBA threshold in the Riverside County noise ordinance. While SCE has raised questions regarding the manner in which Riverside County interprets its noise ordinance, we are not convinced that the finding in the Final EIR/EIS regarding the significant impact of whether corona noise associated with DPV2 should be rejected.
The Final EIR/EIS states that there are few options for mitigating corona noise as it is a function of conductor design and configuration. The Final EIR/EIS describes that SCE would be expected to properly handle the conductor during construction to avoid damage that could undermine the load-carrying capability of the line and exacerbate the corona effect. The Final EIR/EIS does not recommend that SCE be required to purchase or relocate residences, or undertake any other actions to mitigate corona noise impacts.
SCE asserts that the Final EIR/EIS misrepresents that SCE plans to use APM L-7, an applicant-proposed mitigation measure, to mitigate corona noise. APM L-7, included in SCE's PEA, states as follows:
Link 10 crosses an (unoccupied) single-family dwelling unit at Milepost 5.3. Two additional single-family dwelling units and one mobile home would be impacted due to the alignment of Link 10 at Milepost 6.2. Mitigation measures would include purchase of the parcel and relocation or, if practical, adjusting the transmission line alignment and placing towers to avoid the affected dwelling units.
SCE explains that it suggested APM L-7 as a land-use mitigation measure only because DPV2 may cross over 4 residential parcels, such that SCE may have to purchase the properties or exercise its powers of eminent domain. SCE did not mean that it would relocate homeowners to mitigate corona noise. SCE asserts that the Commission should not require SCE to relocate homeowners due to corona noise and, further, that such homeowners may not want to be relocated.
We are persuaded that APM L-7 is relevant to noise impacts only to the extent that, because SCE plans to purchase or relocate dwelling units that DPV2 would cross over otherwise, the identified noise problem would no longer exist for those dwelling units. We see no need to clarify APM L-7 in this regard, as SCE suggests.
Assessment of air quality impacts requires that emissions for the entire DPV2 project be evaluated within each of the affected jurisdictions and/or air basins. As a result, the Final EIR/EIS presents its air quality assessment by jurisdiction rather than by project segment.
The Final EIR/EIS describes expected dust and exhaust emissions during DPV2's construction and operation. With mitigation measures, dust and exhaust emissions during construction would remain below the significance thresholds in areas within the jurisdiction of the Maricopa County Air Quality Department, the Air Quality Division of the Arizona Department of Environmental Quality, and the Mojave Desert Air Quality Management District.
While most of the proposed DPV2 route through the South Coast Air Quality Management District (SCAQMD) in southern California is in remote areas, the western part of the route is in more highly developed areas. In this urban context, SCAQMD experiences more severe baseline air quality nonattainment than the other jurisdictions affected by the proposed DPV2 project. The Final EIR/EIS reports that, even with the recommended mitigation measures, construction emissions would exceed the SCAQMD daily regional significance criteria and, thus, would cause significant and unavoidable (Class I) impacts in the SCAQMD. The Final EIR/EIS makes comparable findings regarding construction impacts of the Alligator Rock, Devers-Valley, and Desert Southwest alternatives, which would be located wholly (Alligator Rock and Devers-Valley alternatives) or partially (Desert Southwest) within the SCAQMD jurisdiction.
The Final EIR/EIS describes that power generated during DPV2 operation would cause emissions from power plants. The CAISO forecasts that, with DPV2, NOx emissions from power plants in Arizona would increase by 200 tons per year and that NOx emissions in California would decrease by 590 tons per year, for a net decrease of 390 tons per year. Similar changes in emissions of other criteria pollutants related to power generation would also occur. The CAISO's assessment is based on 2008 conditions at existing power plants that the CAISO determined to be underutilized in the absence of DPV2. The precise location and quantity of the emissions would change over time depending on the ultimate sources of power flowing into DPV2.
The Final EIR/EIS describes that the identified increase in power plant emissions in Arizona represents an increase of 0.05% of Arizona statewide 2001 NOx emissions and would be within permitted emission levels that have been licensed previously by local air management agencies. The Final EIR/EIS concludes that the increase in power plant emissions in Arizona would be an adverse but less than significant impact of DPV2. The forecasted decrease in California power plant emissions would be a beneficial impact of the proposed project.
15 As described in Section IV.B.1, the 230 kV upgrades in SCE's West of Devers proposal would decrease noise levels along the 230 kV rights of way.
16 The CNEL, or community noise equivalent level, measures the aggregated sound level occurring over a 24-hour period in decibels (dBA), with a 5 dBA penalty added to evening sounds (between 7:00 p.m. and 10:00 p.m.) and a 10 dBA penalty added to night-time sounds (between 10:00 p.m. and 7:00 a.m.).
17 The Ldn, or day-night sound level, is a metric similar to CNEL, but it is less stringent because it omits the 5 dBA penalty that the CNEL measurement applies to evening sounds.
