DOI-BLM-CA-017-05-051

NEPA Document Collection for: DOI-BLM-CA-017-05-051
EA at Long Valley Caldera Geothermal Area for Geothermal/Well Field,

Basalt Canyon Geothermal Pipeline Project Environmental Assessment and Draft Environmental Impact Report for Geothermal/Well Field

Proposed Action

The applicant, Mammoth Pacific, L.P. (MPLP), has proposed to construct, operate, maintain and, following the expected 30-year life, decommission the Basalt Canyon Geothermal Pipeline Project ("Project" or "Proposed Action"). This project is designed to deliver approximately 3,600 gallons per minute (gpm) of geothermal fluid though a new pipeline to two existing MPLP geothermal power plants located eat of the Town of Mammoth Lakes in Mono County, California. The geothermal fluid would be produced from two geothermal exploration wells that would be drilled, completed and tested as part of the previously approved geothermal exploration projects. All of the sixteen previously approved exploration well drill sites are located west of U.S. Highway 395 and north of California State Route 203. All Project activities would be conducted within a 1,660-acre Project area, as shown in Figure S1.

Conditions of Approval

See stipulations section in the attached FONSI.

Data Completion Notes

8/9 Data entry complete. Attached FONSI does not seem to be fully related to the attached EA. The FONSI is for a geothermal well and slimhole exploration project and the EA is for a pipeline project.

Need to add Public Health and Safety as a resource

8/22/13 - The 'FONSI/DR is actually for EA CA-170-02-15 Bassalt Canyon..dated Jan 2002 KW

8/26/13 - I deleted the FONSI from this page. Filename is incorrect for the file and stands as "CA-017-05-51-EA-DR -FONSI.pdf," Andrew Gentile. Unable to find Final EA or FONSI online.

When RMP added, add "Inyo National Forest “Land and Resource Management Plan” (LRMP) 1988"

 

Resource Analysis

Resource	Not Present	Present, Not Affected	Present, Potentially Affected	Not Indicated	Comment	Applicant Proposed Mitigation	Agency Imposed Mitigation

Visual Resources "NEPA_Resource_Analysis" is not in the list of possible values (Not Present, Present, Not Affected, Present, Potentially Affected, Not Indicated) for this property.

The proposed pipeline route would cross areas near U.S. Highway 395 and California State Route 203 that have been designated with a visual quality objective (VQO) of “Retention” by the Inyo National Forest. U.S. Highway 395 is also a California Scenic Highway and State Route 203 is a County Scenic Highway.

CloseThe wellheads, pump motors and motor control buildings would each be painted forest green or another appropriate color to blend with the area and minimize visibility. The fence constructed around each of the production well sites would also be painted an appropriate color to blend with the area. The aluminum sheath cladding the pipeline would also be appropriately colored to blend with the area.

CloseVIS Mitigation Measure 6: The pipeline segments to be constructed on Inyo National Forest managed-land in areas with the VQO of “retention” and visible from State Route 203 and/or U.S. Highway 395 shall use textured pipeline cladding and shall be colored with a color or colors (approved by the authorized officer) to blend with the area so that the pipeline generally repeats the color and texture of the characteristic landscape. VIS Mitigation Measure 7: Following completion of construction, the Permittee shall prepare, submit for approval by the authorized officer, and implement a landscape plan to plant native trees and shrub vegetation at select locations on Inyo National Forest-managed land to further screen from view those portions of the pipeline which may be visible from State Route 203 and/or U.S. Highway 395 to ensure that the pipeline is at least subordinate to the visual strength of the characteristic landscape. VIS Mitigation Measure 8: Following completion of construction, the Permittee shall prepare, obtain the approval of the Mono County and other required parties, and implement a landscape plan to plant native trees and shrub vegetation at select locations on private land to further screen from view those portions of the pipeline which may be visible from U.S. Highway 395 to ensure that the pipeline is generally obscured from view. VIS Mitigation Measure 9A: The Alternative Pipeline Route pipeline segments to be constructed on private land within the scenic highway corridor along U.S. Highway 395 where visible shall use textured pipeline cladding and shall be colored with a color or colors selected (with the concurrence of Mono County) to ensure that the color and structure material are compatible with the natural setting.

Water Quantity "NEPA_Resource_Analysis" is not in the list of possible values (Not Present, Present, Not Affected, Present, Potentially Affected, Not Indicated) for this property.

Production of geothermal fluid from the two wells in the Basalt Canyon area and injection of that fluid into the Casa Diablo injection reservoir through existing geothermal injection wells could alter the pressures and temperatures of these geothermal reservoirs. These geothermal reservoir changes may adversely affect other hydrothermal features (such as Hot Creek Fish Hatchery springs and Hot Creek springs). They may also influence or adversely affect the local or regional shallow, fresh groundwater system.

CloseComputer modeling of the effects of the Project determined that there would be no substantial changes in the pressures in the Casa Diablo geothermal reservoir, and no changes to the geothermal reservoir further east. Therefore, there is no expectation that the Project would adversely affect hydrothermal features (such as the Hot Creek Fish Hatchery springs or the Hot Creek Gorge springs). No potable (drinking quality) ground water is known to exist in the Project area. The existing Mammoth Community Water District ground water production wells are located over one mile, and up gradient, from the closest Project facilities. There is also no current evidence to suggest that the relatively shallow ground water well production zone is hydraulically connected with the deeper geothermal reservoir. Therefore, production of the geothermal fluids by the Project are not expected to adversely affect the ground water well field, either by depleting the aquifer or by drawing in lower quality waters. The pipeline route and construction techniques have been selected to minimize the potential for surface and ground water pollution. The proposed pipeline route is located outside of riparian conservation areas delineated by the USFS. No new permanent or temporary access roads would be constructed, and the pipeline corridor would not be graded.

CloseMPLP would also comply with mitigation measures HYD-4 (hazardous materials with designated RCAs), HYD-5 (preventing impediments to natural flow within designated RCAs), and HYD-6 (protecting designated RCAs from sediment during flood flows) from the Upper Basalt Geothermal Exploration Project ROD. HYD-4: Only nontoxic drilling materials shall be used in the drilling mud or drilling fluids. HYD-5: To prevent cross-contamination of aquifers, geothermal fluids that are produces to the surface and injected shall only be injected back into the same formation from which they are produced. HYD-6: The operator shall acquire all necessary permits and/or agreements, including the completion of any required additional environmental review, prior to any installation of use of reclaimed water for this project.

Threatened and Endangered Species "NEPA_Resource_Analysis" is not in the list of possible values (Not Present, Present, Not Affected, Present, Potentially Affected, Not Indicated) for this property.

Changes to the geothermal reservoir(s) from Project operations could adversely affect the Hot Creek Fish Hatchery springs. This could alter the listed critical habitat of the endangered Owens tui chub, which is dependent on the flow of these springs.

Wildlife Resources "NEPA_Resource_Analysis" is not in the list of possible values (Not Present, Present, Not Affected, Present, Potentially Affected, Not Indicated) for this property.

Mule deer are known to use the Project area as summer range, and possibly as a migration corridor and fawning habitat.

CloseDirect impacts to wildlife habitat and botanical resources would be minimized by clearing only those small areas required for the construction of the road crossings and highway boring. Fish habitat would be protected through the prevention of erosion and spills of geothermal fluid.

CloseFollowing pipeline construction, the few small areas of disturbed land would be reclaimed to promote the reestablishment of native plant and wildlife habitat. MPLP would comply with mitigation measure WLD-1 (vehicle speeds on roads),WLD-2 (operations near goshawk nests), WLD-3 (harassment of wildlife) from the Upper Basalt Geothermal Exploration Project ROD. WLD-1: No operations are permitted during the migration and migration-holding period from April 15 through June 15. WLD-2: Immediately prop to occupancy at site 31+36, a Forest Service biologist will conduct a survey to determine whether new northern goshawk nests have been constructed to the drill pad or access road. If a new nest is discovered, drilling will be delayed until after the nesting season. WLD-3: All drivers accessing drill sites will adhere to a speed limit of 25 MPH.

Range Resources "NEPA_Resource_Analysis" is not in the list of possible values (Not Present, Present, Not Affected, Present, Potentially Affected, Not Indicated) for this property.

The Project is located within the Sherwin/Deadman Sheep and Goat Grazing Allotment of the Inyo National Forest.

CloseAt most less than 8 acres of livestock forage would be temporarily lost through construction of the Project. All but about 1 acre of this lost forage would be restored within a few years following reclamation of construction disturbance. This reduction in forage is a negligible percentage of the capable acres within the allotment.

CloseMPLP would comply with mitigation measure GRZ-1 (coordination with the USFS and term grazing permittee during drilling and testing operations) and GRZ-3 (coordination with the USFS and term grazing permittee) from the Upper Basalt Geothermal Exploration Project ROD. GRZ-1: If required by the authorized officer, the operator shall fence active pads sufficiently to prevent access by grazing animals. GRZ-3: The Authorized Officer, in conjunction with the Forest Service, will identify alternate bedgrounds or other permittee use areas, if exploration-drilling operations displace the permittee's use. The geothermal operator will be responsible for reclaiming all new or old bedgrounds that are abandoned as a result of drilling operations, including revegetation and weed control.

Fire Resources "NEPA_Resource_Analysis" is not in the list of possible values (Not Present, Present, Not Affected, Present, Potentially Affected, Not Indicated) for this property.

ClosePersonal vehicles and vehicles not in use during construction would be parked on existing well pads or at locations along existing access roads where they would not risk igniting vegetation from hot exhaust pipes.

CloseAll construction and maintenance equipment would be equipped with exhaust spark arresters. Fire extinguishers would be available on construction and maintenance vehicles. Water that is used for construction and dust control would be available for fire fighting. Personnel would be allowed to smoke only in designated areas, and they would be required to follow applicable Inyo National Forest regulations regarding smoking. Any special permits required for welding or other similar activities would be applied for through, and received from, the District Ranger before these operations are conducted.

Air Quality "NEPA_Resource_Analysis" is not in the list of possible values (Not Present, Present, Not Affected, Present, Potentially Affected, Not Indicated) for this property.

CloseMPLP would comply with any requirements prescribed by the Great Basin Unified Air Pollution Control District (GBUAPCD) concerning emissions of air pollutants from construction engines or hydrogen sulfide from operating geothermal wells. MPLP would also comply with mitigation measure AIR-4 (watering to control dust during construction) from the Upper Basalt Geothermal Exploration Project ROD. AIR-4: The permittee shall apply water during the construction and utilization of pads and access roads as necessary to control dust. Dust shall not be discharged into the air for a period or periods aggregating more than three minutes in any one-hour that is as dark or darker in shade as designated as No. 1 on the Ringelmann Chart.

Noise "NEPA_Resource_Analysis" is not in the list of possible values (Not Present, Present, Not Affected, Present, Potentially Affected, Not Indicated) for this property.

CloseConstruction noise would be minimized through operational practices which avoid or minimize those practices which may typically generate greater noise levels, or generate distinctive impact noise.

Public Health and Safety "NEPA_Resource_Analysis" is not in the list of possible values (Not Present, Present, Not Affected, Present, Potentially Affected, Not Indicated) for this property.

CloseField contingency and emergency plans prepared for the proposed operations, presented as Appendix B to the Plan of Development, describe those actions to be taken by MPLP employees and contractors to first prevent; and if they occur, respond to; different incidences (well blowouts, fire, spills or geothermal fluid discharges, and hazardous gas discharges) which could endanger public health and safety. The measures and programs designed to prevent and control any unlikely accidental discharges of geothermal fluid, as described above in Surface and Ground Water Quality Protection, also work to protect public health and safety from these same potential discharges of geothermal fluid. MPLP safety training and instructions to work crews and contractors concerning public health and safety, and compliance with Cal/OSHA regulations, also help protect public health and safety.

Soils "NEPA_Resource_Analysis" is not in the list of possible values (Not Present, Present, Not Affected, Present, Potentially Affected, Not Indicated) for this property.

CloseNo clearing of the pipeline route is proposed. Cut and fill activities would be restricted to construction of the road under-crossings. Off-site storm water would be intercepted in ditches and channeled to energy dissipaters as necessary to minimize erosion.

CloseUSFS and State of California best management practices for storm water would be followed, as applicable, including USFS BMP-28 (Surface Erosion Control at Facility Sites). MPLP would also comply with mitigation measure HYD-1 (implementation of best management practices to prevent erosion and sedimentation), SMG-1 (salvage of topsoil), and SMG-2 (de-compacting subsoils) from the Upper Basalt Geothermal Exploration Project ROD. HYD-1: The permittee shall use the following BMPs to ensure the full containment of all sediment that may be generated by sotorm water runoff form the construction of each pad and access road throughout the life of the project: - Erosion Control Plan (BMP 2.2) - Timing of Construction (BMP 2.3) - Stabilization of Road slope Surface and Soil Disposal Areas (BMP 2.4) - Snow Removal Control (BMP 2-25) This mitigation measure shall be implemented by developing a plan to prevent storm water pollution, which plan shall be prepared prior to construction of each well pad and access road. This plan shall identify structures such as sediment traps, filter fences, straw bales, or activities that will implement the intent of the BMPs. The permittee shall be responsible for ensuring that the identifies BMPs are implemented immediately as required or applicable throughout the course of the exploration activities. SMG-1 and SMG-2 were not found in the ROD.

Vegetation "NEPA_Resource_Analysis" is not in the list of possible values (Not Present, Present, Not Affected, Present, Potentially Affected, Not Indicated) for this property.

CloseMPLP would also comply with mitigation measures VEG-1 (reclamation and revegetation of disturbed areas) from the Upper Basalt Geothermal Exploration Project ROD. VEG-1: Upon completion of operation, all Project-affected areas of surface disturbance would be re-contoured as necessary to blend with the surrounding topography. Partial, phased, or concurrent reclamation may be required by the authorized officer as appropriate to minimize erosion and stabilize the disturbed areas. Salvaged and stockpiled topsoil would be resitribued over the re-contoured disturbed areas. Seeding of the disturbed ara would be completed using the BLM approved seed mixture and application rate.

Invasive, Nonnative Species "NEPA_Resource_Analysis" is not in the list of possible values (Not Present, Present, Not Affected, Present, Potentially Affected, Not Indicated) for this property.

CloseMPLP would also comply with mitigation measures NOX-1 (washing of construction vehicles), NOX-2 (weed-free seed mixtures), NOX-3 (weed-free erosion control materials), NOX-5 (non-native weed species standards for revegetation), NOX-6 (cheatgrass control), NOX-7 (rehabilitation of disturbed areas) from the Upper Basalt Geothermal Exploration Project ROD. NOX-1: Prior to entering the project area, all trucks and construction equipment that will operate off of previously existing roads shall be washed to remove soil and plant parts. A central washing facility will be provided for this purpose, either at the MPLP equipment area at Casa Diablo on private land or at a location approved by the authorized officer. Vehicle inspections will be conducted by an authorized representative to verify the absence of noxious plant propagules. Prevention is a high priority. NOX-2: Where appropriate, seed mixtures used to revegetate disturbed areas would be certified as being free of noxious weed materials. In some cases, e.g. when seed is collected locally vs. grown in a nursery setting, weed certification may not be available. NOX-3: All other materials used in erosion control or rehabilitation efforts, e.g. straw bales, would be certified as being free of noxious weed materials. NOX-5: All non-native weed species already present in the area would account for no more than 5% total of the relative cover at the end of the 3-year evaluation period, following completion of revegetation measures. New non-native species introduced as a result of the Project will be eradicated (i.e. 0% cover). Where this standard is not met, appropriate weed control measures will be implemented in order to comply with the standard for a period of three years following project completion. NOX-6: Cheatgrass is largely absent from the forested portions of the Project area. In order to maintain this condition, cheatgrass will be removed from all areas where ground disturbance occurs. Appropriate weed control measures will be implemented as necessary, in order to prevent the invasion and spread of cheatgrass, throughout the life of the project, and for a period of three years following Project completion. NOX-7: Disturbed areas will be rehabilitated according to USFS specifications.

Cultural Resources "NEPA_Resource_Analysis" is not in the list of possible values (Not Present, Present, Not Affected, Present, Potentially Affected, Not Indicated) for this property.

With exception of approximately 20 acres of private (fee) land owned by the City of Los Angeles, all of the Project area has been previously surveyed for cultural resources. Although some of these cultural resource surveys are old, they indicate a relatively low density of identified cultural resources, and thus the likelihood that all important cultural resources can be avoided by Project surface disturbing activities.

CloseMPLP will contract for an archeologist acceptable to the Inyo National Forest Archaeologist to conduct site-specific surveys of those Project areas which may be disturbed prior to conducting any activities which would disturb these areas. Any areas which contain cultural resources of significance will be avoided, or the potential for impacts mitigated in a manner acceptable to the Inyo National Forest Archaeologist.

CloseMPLP would also comply with mitigation measures CUL-1 (conducting cultural resource surveys prior to any new surface disturbance and protecting identified resources during construction) and CUL-2 (protecting previously unrecorded cultural resources which may be encountered) from the Upper Basalt Geothermal Exploration Project ROD. CUL-1: Each area proposed for any new surface disturbance, including an appropriate buffer, would be surveyed by a professional archeologist acceptable to the BLM/USFS, and the results of this survey would be reported to the BLM/USFS with the request to commence surface disturbance. Drill pad and access roads would be considered in such a way so as to ensure that recorded archaeological site materials are either disturbed or, if they need to be disturbed, that they are inventoried, documented, and reported to the BLM/USFS, and a determination of their eligibility for the National Register of Historic Places and appropriate mitigation, if any, be completed by the BLM/USFS prior to disturbance to the site. To ensure that identified cultural resource sites adjacent to areas of disturbances are not disturbed, the limits of surface disturbing activities, including an adequate buffer zone, would be clearly marked and flagged prior to the start of all grading or other surface-disturbing activities. The flagging would be set with the assistance of a professional archaeologist, and the construction/grading contractor and each of the workers would be trained to understand flagging and its importance. CUL-2: If previously unrecorded cultural resources are encountered during grading or other surface-disturbing activities, all grading or other surface-disturbing activities at the location of discovery would cease, and the authorized officer notified. Grading or other surface-disturbing activities would not recommence at the location of discover until the identified cultural resource(s) have been assessed, and necessary mitigation actions taken, and the expressed approval of the authorized officer or his designee granted.

Recreation "NEPA_Resource_Analysis" is not in the list of possible values (Not Present, Present, Not Affected, Present, Potentially Affected, Not Indicated) for this property.

CloseMPLP would also comply with mitigation measures CUL-1 (conducting cultural resource surveys prior to any new surface disturbance and protecting identified resources during construction) and CUL-2 (protecting previously unrecorded cultural resources which may be encountered) from the Upper Basalt Geothermal Exploration Project ROD (see Appendix C). Winter access to the well sites by vehicles when substantial snow is on the ground is unlikely but could be required to complete critical Project maintenance operations, such as the replacement of a well pump. In these circumstances it may be necessary to plow, blow or otherwise remove snow from the well site access routes. As Sawmill Cutoff Road is a signed and groomed snowmobile trail, MPLP has committed that, to the extent possible, all access to producing well sites which would require the removal of snow would be on Sawmill Road off of State Route 203. MPLP has also committed that should well sites 12-25, 14-25, 15-25, 25-25, or 34-25 be connected to the pipeline, MPLP would consult with the BLM and USFS and prepare a winter access contingency plan to specifically describe how any critical maintenance operations would be conducted during winter to minimize the adverse effects on snowmobile and cross-country ski use of the Sawmill Cutoff Road trail or surrounding areas. The contingency plan would specify one or more of the following or other actions which would be appropriate to minimize the effects on recreation from the required maintenance operations should the clearing of snow become necessary: • Minimize the length or width of the road cleared of snow; • Minimize the time during which snow is cleared from the road; • Direct the replacement of removed snow after the completion of the drilling operations; or • Limit the crossing of Sawmill Cutoff Road to a single, ramped cut along the “Pole Line Road” west to Forest Road 3S35 northwest of Shady Rest Park or to Forest Road 3S35 near drill site 34-25, which could be accessed from Sawmill Road through either the Shady Rest Park parking lot and Forest Road 3S26 or the new and existing access roads through drill sites 77-25 and 56-25. MPLP would install temporary warning signs and devices along Sawmill Cutoff Road, in conformance with USFS recommendations, to alert snowmobile drivers of the vehicle crossing hazard at the Sawmill Cutoff Road/”Pole Line Road” junction and/or in other locations, as needed. Temporary warning signs would also be posted along the cross country sections of the pipeline during winter to warn snowmobilers and skiers of the pipeline should it become covered with snow.

CloseMPLP would comply with mitigation measures TPS-5 (proper signage to avoid conflicts with winter recreation users along Sawmill Cutoff Road) and REC-1 (crossing Sawmill Road by cross-county skiers) from the Upper Basalt Geothermal Exploration Project ROD (see Appendix C). TPS-5: Should winter access be necessary and facilitate the cutting across of Sawmill Cutoff Road from the "Pole Line Road," proper signage would be prominently placed alerting the winter recreation user of the cut so as to avoid conflicts. REC-1: The Winter access contingency plan would ensure that there is as least one location along Sawmill Road which would be maintained to provide a safe and easy crossing by cross-country skiers.

Wastes Hazardous or Solid "NEPA_Resource_Analysis" is not in the list of possible values (Not Present, Present, Not Affected, Present, Potentially Affected, Not Indicated) for this property.

CloseFew solid waste materials would be generated. Solid wastes generated during construction would either be collected by a licensed waste hauler or transported by MPLP and deposited at a facility authorized to receive and dispose of these materials. Portable chemical sanitary facilities would be used by all personnel. These facilities would be maintained by a local contractor.