September 21, 1998
Mr. Bruce Kaneshiro, Project Manager
c/o Environmental Science Associates
225 Bush St., Suite 1700
San Francisco, CA 94104
Re: Draft Environmental Impact Report comments, CPUC Application #98-01-008 Geysers Geothermal Power Plant & Other Divestitures
Dear Mr. Kaneshiro:
District staff has reviewed the referenced document sections related to the air quality issues involved in the pending sale of the PG&E Geysers Power Plants. The District asks that major concerns identified below and the specific comments provided in Attachment #1 be addressed in the final EIR. The background information provided regarding the pending sale and the potential new owners is informative, as are the discussions regarding the various projections for continued operations under the various scenarios, but we do consider them incomplete. We are concerned about conceptual errors and the avoidance of identifying any suggestion of mitigation for the scenarios chosen in the DEIR.
Major Concerns
[Begin H1]Our major concern continues to be the possibility of plant management under a new owner incompatible with maintaining the integrity of the steamfields. The document should emphasize repeatedly that adverse air quality impacts in Lake County are largely a result of the operations of the applicant’s power plants, and when the plants are not operating, the associated steamfields located in Sonoma and Lake counties.
[End H1]
[Begin H2]There are a number of reasons for our concerns in this regard for the Sonoma County units including less advanced technical designs, aged equipment, differing operating conditions and poorer steam quality among others.
[End H2]
[Begin H3]The issue of avoiding steam stacking is extensively noted, however we need to emphasize any condition which results in the atmospheric release of untreated steam is at issue and the cumulative impact of well field bleed flows at well pad locations is of equal or greater concern due to the closer proximity to residents, because of poor plume rise and reduced pollutant dispersion. Additionally, when steamfields are extensively curtailed, well maintenance including the need for deep drilling rig utilization and increased numbers of well blow downs to remove water or rock bridges all contribute to increased emissions.
[End H3]
[Begin H4]The "must run" contracts have been offered as a reason that hydro or other curtailments should not be a significant concern. Yet, must run class "B" may be needed only a few hours per year (Pg. C-ii). This needs to be clarified as to how effective it is and what to expect in the future as regards to the minimum power generation available to the steamfield owners. Apparently, except for Units 5-8, it is just a peak temperature requirement and is unlikely to be relevant to hydro curtailment. Please clarify and explain.
[End H4]
[Begin H5]The situation as presented in the DEIR included a reference to a less than 2.2¢/KW power cost and periods of zero price during the present year. Please explain how this will similarly affect the Geysers’ need for a minimum production to avoid steam venting. If that can not be ensured in the future, consider the below scenario and suggested mitigation for inclusion in the EIR.
[End H5]
[Begin H6]Were AB 1890 funds used to stabilize the price, and if so at what level? Was the price driven down because of abnormally high availability of hydro power? What is considered an economic price? If you conclude as indicated at the 9/15/98 meeting that this is unlikely because of the price of power and the production cost, state and support your assumptions clearly in the EIR. AB1890 apparently provides limited funding to stabilize pricing during the transition years. Will this funding be available to the new owners, or once they are sold will they be considered merchant plants? How significant is the loss of resources of PG&E whom still has a virtual monopoly on customers and extensive hydro power?
[End H6]
Given the above discussion, please consider the following scenario and suggested mitigation for comment.
Scenario #1
[Begin H7]Identified Potential Impact: The market economy is such that generation units are prevented from selling the power to the PX and no direct customer delivery is possible. The plant owners shut down all the plants to zero production. The units then must stack, by-pass and/or close in the steamfield with resulting water logging of wells, thermal stress and production well failure. The impact on air quality, water quality and the land is significant from the vented steam and emissions associated with repair (none of the emissions are necessarily stacking). The steamfields become less profitable and threaten the overall viability of electrical power generation and a loss of this green power resource.
Suggested Mitigation: Ensure that a minimum production is allowed and deliverable from each of the two facilities (Lake & Sonoma). Methods to accomplish this could include: 1) a reserve of approximately 50 and 110 Megawatts at the ISO being set aside specifically for the Lake and Sonoma Geysers plants respectively that would be under a must run continuous agreement; 2) requiring the purchaser (and future purchasers) to operate the facility using a continuous direct purchase customer for at least the sustaining portion of the production; 3) committing the smaller negotiated quantity of generation as a RMRA "A" to include hydro-curtailments; or 4) utilize a distribution benefit charge through the PX/ISO that will support and make viable this minimum production capacity for this specific existing (stranded) green power and ensure that it is bid into the PX (with a general benefit subsidy, if necessary, much like the AB 1890 is now providing).
[End H7]
[Begin H8]We are in agreement that Alternative 3 (sale to steam suppliers) is likely the environmentally best alternative, provided they have the financial strength to maintain the facilities and this green power remains cost competitive. The District is not in agreement with the conclusions in Table S.2 regarding the air impacts being less than significant, as that assumes an approximate 10% change on an annual basis. This does not consider the significant impact of a single or several individual events. There is no mitigation to assure that the plants will be operated at a level at all times sensitive to preserving air quality.
[End H8]
[Begin H9]The modeling analysis for the geothermal units predicts emissions variability of between -13% and + 39%, depending on the analysis scenario, with the Sonoma County units accounting for the majority of the increase. Many of these units are approaching their design life span and have higher air emissions potentials due to their date of construction, less advanced technical design, increased maintenance requirements and poorer steam quality. As the emissions from these units predominantly impact the Lake County public, and have been the source of significant air quality complaints and AAQS exceeds in the past, a 40% increase in emissions is considered by the District as significant and thus we would require mitigation. In reality such is not likely to happen unless a choice to change the abatement systems operational techniques is implemented by a new owner, as the abatement systems (especially of newer plants) perform superior to present permit emission limitations. (See Exhibit A attached that lists the permitted and actual emissions as tested recently for units being divested.) Again, this is a case of performance superior to what is required under regulations, especially for the newer units. Similarly the use of mercury scrubbers (while under permit) are not regulatorily required, since cooperation was high and a variety of incentives existed.
[End H9]
[Begin H10]The Geysers Air Monitoring Program (GAMP) represents a consortium, and while the regulatory alternative exists, participation is voluntarily renewed by MOU. Present PG&E staff displays a sensitivity and concern for safety, the public and the environment and their programs have clear corporate support. The potential of changing from a monopoly, or to a company without PG&E resources, is of concern.
[End H10]
Given the above discussion please consider the following scenario and suggested mitigation for comment.
Scenario #2
[Begin H11]Identified Potential Impact: The new owner takes only the steps that are specifically required by permit as an economy measure and decides not to participate in efforts jointly or separately. These efforts include seismic monitoring, air monitoring, the use of an iron chelate catalyst in secondary abatement and the use of mercury scrubbers on the Stretford equipped units. This results in less information on which to document environmental management success, less public trust, greater emission releases and less efficient management approaches to the overall resource area.
[End H11]
[Begin H12]Suggested Mitigation: Ensure that the new owner participates in GAMP, the seismic monitoring program continues, they continue to use Hg scrubbers and use innovative H2S technologies presently installed.
[End H12]
[Begin H13]The DEIR is long on discussion but slightly off target as to the interaction of the power plant and steamfield operations. The policy implications of green power also need to be further enlarged upon as part of this first significant green power divestiture decision by the CPUC. The document provides little in finding significance in the divestiture of the subject plant and thus avoids having to recommend mitigation measures. The major issue for the AQMD is not just steam stacking but managing (production assurances) in a manner that ensures the physical integrity of the steamfields without stacking, field wide emission or threatening the long term integrity of field operations and production. We do not believe that we are being overly cautious in attempting to be protective of our air resources and requesting assurances that the Geysers steam resource is adequately protected from misuse and abuse, be it intentional, market driven or unwitting. The remarks regarding the economic incentive to defer maintenance and utilize plant malfunctions to increase the rate basis is disturbing, and is counterproductive to both resource management and air quality. The knowledge regarding the wise management of the Geysers resources and compatibility with good environmental management has been an acquired learning experience gained over a period of more than 30 years. It is imperative that this knowledge and understanding be retained and that we wisely proceed and assure that this goal is nurtured to the extent possible.
[End H13]
[Begin H14]We are concerned that this first sale of green power by a monopoly utility is occurring without an assessment of policy or the implications of a lack of policy and we ask that such be incorporated into the EIR as a relevant and necessary part of the scope required. We will not repeat past comments of the uniqueness and environmental advantages of the Geysers and green power in general, as we have all been educated by the past events and prior or existing state policies.
[End H14]
[Begin H15]In discussions before the Lake County Board and elsewhere, two responses have always come forward from CPUC/ESA staff: 1) that there is a willingness for consumers to pay more for green power, and 2) that the federal legislation gives the Geysers a 1.5-cent/KW advantage. While we hope this is correct, we want such to be clearly and correctly evaluated as part of the EIR.
[End H15]
[Begin H16]Renewables (green power) are apparently 11% of the present PG&E profile and geothermal is approximately 7% of the total. Is the present niche market for green power that large? Is it likely, given that the label "green power" need only to include 50% green power, that this niche market can adsorb 10-22% of the existing total market? Will the niche market be sustainable in times of a depressed economy? What specifically are the state policies that are in place which recognize the advantages of indigenous green power to our state and country? Please summarize the hidden environmental, national defense, green house gas, economic, and other costs of nuclear and fossil fuel and the advantages to society of nurturing and promoting "green power"? Please at least summarize a response in the final EIR.
[End H16]
[Begin H17]Please consider in your discussion the timing and status of the CPUC green power certifying/ labeling and emissions disclosure on customer billing; the possibility of an ISO distribution benefit charge to enhance green power sustainability; reduced charges on the PX exchange; preferential financing; lessening the PX buy in cost; and other suggestions as are contained in the National Association of State Energy Officials "Energy Efficiency and Renewable Energy Sources: A Primer" dated July 1998. These issues in are relevant to our society and should be relevant to the CPUC decision to approve the sale with or without mitigation.
[End H17]
Sincerely,
Robert L. Reynolds, APCO
Attachments: Specific Comments
Exhibit A
CC: Board of Directors
Interested Parties
RLK/RLR
Attachment #1
Specific Items of Comment
[Begin H18]In Tables S.1, S.3, S.5 (and elsewhere) and Table 2.1 (Description of Facilities) there appears to be a significant difference between the projected scenario annual capacity factors for the Lake County units shown which should be elaborated upon. The DEIR states that the Analytical Maximum Scenario is the "conservative" approach and in the case of the Geysers represents a minimum operating level (worst case). While we understand what this is attempting to convey, it is somewhat confusing and represents approximately a 10% reduction in capacity over the no project alternative. The DEIR is vague on the factors which result in this being the "worst case" and does not recommend if this is the minimum level of operation necessary to preserve the existing air quality (Section 3.6.2 end of paragraph 2) or that this will be a regulatory limit imposed on the buyer. This is where the "must run" contract requirements need to be specific enough to ensure that adverse air quality impacts are minimized, or it acknowledged that they are of little relevance.
[End H18]
[Begin H19]Page 2-26 Geysers Power Plant. Mining was an important historical previous use but has been very limited in the past 40 years to limited aggregate associated with geothermal development and otherwise to recreational prospects. Timber harvests have occurred within the area and the most significant adjacent land uses are recreational, residential and bottled drinking water production.
[End H19]
[Begin H20]Page 2-35 Geysers Geothermal Field. The Geysers field is more roughly 10 miles long by 4 miles wide although the Known Geothermal Resource Area (KGRA) is more extensive. Surface manifestations of thermal activity occur throughout the area, however it is acknowledged that major early development centered on the Geyser Creek/Geyser Canyon area.
[End H20]
[Begin H22]
Page 2-38 Geyser Power Plant Units (paragraph 3). More correctly, the steam contains hydrogen sulfide and other reduced sulfur compounds which exist in both a dissolved and gas phase. A portion of the hydrogen sulfide remains dissolved in the liquid condensate and is subsequently chemically treated to maintain solubility and prevent "air stripping" in the cooling tower. The non-condensible gas is treated to convert the H2S to elemental sulfur or SO2 using a Stretford or Incinerator system respectively. The elemental sulfur is more commonly produced as a "sulfur cake or slurry" product more so than a molten material (both are elemental sulfur); the SO2 is removed using a scrubber system and the resulting solution re-injected. The description in Table 2.2 contains a better description of the process. Flow diagrams Figures 2.18 and 2.19 lack the abatement chemical inputs. Abatement system failures on single units in Sonoma County can cause ambient air quality exceeds in Lake County under various conditions.
[End H22]
[Begin H23]Page 3-12, 3.6.2 1999 Analytical Maximum Scenario (last four sentences of the first paragraph). The 230KV line outage results in simultaneous multiple plant outages and is of concern during coincident periods of poor air dispersion. The District’s concern regarding hydro curtailment is acknowledged, however paragraph (3) is a disclaimer that any particular plant may not operate within range of capacity factors cited. The District is also concerned that the plants receive ongoing preventative maintenance and upgrades where feasible to reduce unexpected maintenance, related temporary shutdowns and resultant emissions. Again, analysis on an annual basis misses short term, event driven, emissions impacts.
[End H23]
[Begin H24]Chapter 4, 4.1.1 Sonoma and Lake Counties - The reference to a "series of geysers" is likely a reference to a "series of geothermal power plants". Retirement residential and related services are also a major factor in the economy of Lake County. This is an important distinction considering the expanded government service requirements and the sensitivity to air pollutants of the receptor population.
[End H24]
[Begin H25]Page 4.1-4 Geysers Power Plant - While the Sonoma county portion of the Geysers is sparsely inhabited, the Lake County portion is within or adjacent to community residential, recreational (camps, retreats) and rural residential development. We are not aware of any active mining activity other than geothermal resource exploitation.
[End H25]
[Begin H26]Page 4.2-10 Geysers Power Plant - The comparison of the number of jobs relative to Sonoma County is not representative of the impact on Lake County (where a large proportion of the workers reside).
[End H26]
[Begin H27]Page 4.3-6 Geysers Power Plant - Geologic description should include serpentine as a significant rock type present in the Geysers. Serpentine is of concern due to its asbestos content and potential for airborne release.
[End H27]
[Begin H28]Page 4.5-4 (top of page) Discussion of pollutant transport should emphasize that the regional northwest winds transport pollutants from the Sonoma County power plants into inhabited communities within the Lake County Air Basin (Glenbrook, Pine Summit, Cobb, Anderson Springs, Middletown).
[End H28]
[Begin H29]Page 4.5-8 Hydrogen Sulfide - Is highly toxic and lethal at concentrations of 1,000 ppm. H2S concentrations in the geothermal steam varies by location, usually in the range of 50 -1,200 ppm. H2S concentrations in the non-condensible gas is within the range of 10,000 - 50,000 ppm.
[End H29]
[Begin H30]Page 4.5-9 Table 4.5-2 Lake County Air Basin, Particulate Matter (PM-10)d. The footnote refers to the new federal PM 2.5 standard. In addition to the PM 2.5 standard, a modified federal PM-10 standard was also retained.
[End H30]
[Begin H31]Page 4.5-20 Lake County AQMD Regulations, Plans and Policies (first paragraph); The 40 lb/hr particulate emission limit is from the District Rule 411. The source of the cited 15 lb/hr H2S limit is not known and oversimplified. The District has general regulations limiting sulfur emissions from various sources, set at various concentration and mass emission limits. Power plants are subject to New Source Review and Best Available Control Technology (BACT). BACT is project specific and for the existing Lake County units has been defined as emissions of not more than 5 lb/hr H2S per million pounds of steam used. The District’s authority to construct and permits to operate further refine and restrict project emissions based on the New Source Review assessment of project emission impacts on the closest receptor.
[End H31]
[Begin H32]Page 4.5-45 Paragraph (2); The PM-10 monitoring data includes analysis by XRF for the elements cited. Ambient radon concentrations are also measured at the Glenbrook and Anderson Springs sites.
[End H32]
[Begin H33]Page 4.5-46, Table 4.5-19 "Particulate Matter (PM-10)". Data is available for Glenbrook and Anderson Springs (both located adjacent to and downwind of the Geysers). This GAMP data should be utilized in this table as representative of geothermal impacts.
[End H33]
[Begin H34]Page 4.5-46 Existing Emissions (first sentence). Include benzene and radon in the category of "other gasses". Geothermal air pollutants are not generally emitted from steam wells, steam transmission lines and steam stacking facilities under normal operations. Steam is emitted during well construction, testing and maintenance operations. Most of the geothermal emissions are from the cooling towers and gas treatment facilities. While well bleeds and well maintenance is currently the largest "steam field" emission source, steam field emissions are relatively insignificant when the power plant is operating.
[End H34]
[Begin H35]Page 4.5-47, top of page; Most of the air pollutant emissions during normal operations are from the evaporation of the circulating water and "air stripping" which occurs in the cooling towers (provided the gas treatment systems are properly functioning).
[End H35]
[Begin H36]Paragraph (2): Steam Stacking is more properly a result of the power plant’s inability to utilize the available steam rather than a slowdown in use of the steam wells. The "slowdown" is typically an immediate 100% rejection of steam flowing to the plant. While stacking is an immediate and usually short term occurrence, such was not always the case previously.
[End H36]
[Begin H37]Paragraph (3): Of greater concern now is a condition where a power plant is not operated (for mechanical or perhaps economic considerations) and the steam wells have to be shut-in to a sustaining steam bleed rate consistent with maintaining well integrity for extended periods of time. The cumulative impact of such action has a greater impact potential due to the large number of wells involved, their location closer to residents and the lower air dispersion characteristics of the bleed flows as compared to the massive stacking flow rates.
[End H37]
[Begin H38]Paragraph (4): Ambient radon measurements continue to be part of the Geysers Air Monitoring Program. The measurements show ambient radon concentrations of 0.3 - 0.5 pico-curies per liter (not 3 -5 pico-curies) and these values are considered background and are within the range of reported background concentrations for many areas in the United States.
[End H38]
[Begin H39]>Page 4.5-49 Tables 4.5-21 and 4.5-22; Since the Geysers Power Plant emissions primarily impact Lake County residents, the Tables would be more descriptive if the emissions were all compared as a percentage to the Lake County emissions inventory.
[End H39]
[Begin H4]0Page 4.5-50 (top of page) ; The reference exposure levels used in calculating risk are currently under review by OEHHA and it is expected that the revised values may result in a significantly higher calculated risk.
[End H40]
[Begin H41]Page 4.5-60 (Tables 4.5-27 and 4.5-28). Are the Baseline and Analytical Maximum emissions estimates in these tables different than those presented in the Executive Summary and Section 3 where analytical maximum was a minimum capacity factor? Are the emissions factors utilized based on test data or permit limits? If permit limits are the basis, emissions would not be expected to change, if operating data is utilized, do the estimates consider that the new owner will continue to control emissions to less than (at times considerably below) the permit limits? The difference between actual and permitted emissions can be significant. For Lake County Unit #16, actual emissions are approximately 3.5 times lower than allowed by the permit for H2S and 16.5 times lower for particulate matter. The EIR should address whether or not the new owner will operate the plants similarly. If realized, the projected 40% increase in emissions from the Sonoma County units would appear to be capable of a significant impact. Of greater concern to the LCAQMD is an increase in "uncontrolled" emissions due to economics, reliability or maintenance factors.
[End H41]
[Begin H42]Page 4.5-75 Geysers Power Plant; Although steam stacking has been shown as a cause of AAQS exceeds the same can be demonstrated for emissions from untreated well bleeds, normal and abnormal power plant operations as separate and cumulative sources. Cumulative steady state "controlled" emissions are capable of, and have been the source of both nuisance complaint generation and AAQS exceeds. These events are typically associated with episodes of regional air stagnation and a "flushing" of built up pollutant concentrations from West Geysers area into Lake County during the early afternoon wind flow reversal from a westerly direction. The approach here in the DEIR is too simplistic and ignores the various complexities discussed above.
[End H42]
[Begin H43]Page 4.5-76 Geysers Power Plant; The reference to the absence of combustion sources and acidic particulate does not consider the operation of the "incinerator" abatement systems and SO2 emissions from both the abatement systems and the atmospheric oxidation of H2S to H2SO4. A less than significant impact from FTP would be expected due to the proximity and elevation distances between the source(s) and receptors rather than the absence of combustion sources.
[End H43]
[Begin H44]Page 4.8-2 (Paragraph 1) Economic curtailment is a significant concern if it results in untreated steam releases such as would occur if the production wells were required to be placed on bleed flows or the wells were damaged due to excessive thermal stress (thus requiring extensive maintenance and maintenance related emissions). This is an important point and should be in body of the text and not a footnote.
[End H44]
[Begin H45](Paragraph 2) Many of the Geysers Power Plant units have reached or are approaching their 25 year design lifetime. It is expected that the inefficient older units will be abandoned and the remaining marginally efficient units reconstructed to make efficient use of the lower pressure steam resource. We believe it is important to efficiently utilize this valuable, renewable and more environmentally sound resource through careful management and in so doing preserve the air quality. This should be accomplished by efficiency improvements and operating the plants at flow rates that are sustainable and protective of the steam production facilities (some form of sustainable base loading).
[End H45]
[Begin H46]Page 4.8-1 Impacts and Mitigation Measures; No mitigation measures are proposed and the DEIR represents that none are required despite obvious adverse and significant impacts should the power plants be operated inefficiently or without regard to protecting the steam supplies. This section needs additional review and mitigation to assure that power plant operations remain consistent with good management practices which are protective of this valuable resource. We suggest appropriate "must run" agreements and regulatory support to assure that this power resource is preserved.
[End H46]
[Begin H47]Page 4.9-12 Hazardous Materials and Waste (Paragraph 2) Mercury and arsenic are two important additional hazardous constituents of the geothermal steam which are concentrated in the power generation cycle at various locations. PG&E constructed and operates "hygiene facilities" at each of the Geysers power plants primarily in response to concerns regarding exposures to these two materials.
[End H47]
[Begin H48]Page 4.9-19 - 4.9-20 Hazardous Materials; Add hydrogen sulfide, arsenic, mercury and possibly radon as hazardous components of geothermal steam which are found in significant concentrations at the Geysers power plants. It should be noted that concentrations of asbestos >1% is associated with serpentine rock and soils which are common to the Geysers area and possibly on properties considered for divestiture. The District believes that Unit #16 is located on or adjacent to property extensively mined for mercury.
[End H48]
[Begin H49]Page 4.12-11 North Geysers Unit Loading Instructions; Current and planned future modifications to system loading requirements and transmission line improvements should consider promoting the optimal use of the steam resource and electrical generation from the Geysers, especially as it relates to a sustainable base loading of units and transmission line reliability.
[End H49]
[Begin H50]Page 4.12-14 Sanitary /Storm Sewers; Although this may or may not be the location in the DEIR to discuss this issue, it should be emphasized that the operations of Regional Wastewater Plants in Lake County are tied to the operations of the Geysers via the Geysers Wastewater Pipeline Project. Operational changes at the power plants should consider not only impacts to the steam suppliers but also the Lake County Sanitation District and the general economy of the county relative to the economic continuance of these essential services.
[End H50]
[Begin H51]Page 4.12-15 Solid Waste; The Clearlake Landfill is a public County of Lake Solid Waste facility located in the City of Clearlake. Geothermal wastes were previously transported to the IT Benson Ridge site (a now closed facility) and also to GII site located on Butts Canyon Rd., Middletown. The GII site received PG&E wastes and is in the process of sorting out the responsibilities for remediation costs. The Geysers continue to produce both solid and liquid industrial wastes (both hazardous and non-hazardous). Those materials, amounts and locations should be identified either in this section or in Section 4.9.
[End H51]
[Begin H52]Page 4.12-17 Electricity (Paragraph 1) The ISO coordination and dispatch to maintain reliability of the transmission system presumably will minimize line outages which have recently occurred. It should be noted that the PG&E Geysers plants do not generally have the ability to produce "in house load" power for critical component operation during line outages, but must rely on external line power for pumps, fans and controls necessary to rapidly return to production after a line fault is cleared. Air emissions during extended start up conditions have been/can be significant.
[End H52]
[Begin H53]Section 5.3.2 Cumulative Effects by Environmental Topic.
See comments above in reference to Section 4.5, Air Quality.
[End H53]
[Begin H54]Page 5-33 Noise - Geysers Power Plant; Steam Stacking occurs through the "stacking mufflers" located at each power plant. This operation is not normally a significant noise source. Power plant operations which result in unmuffled steam releases, produce harmonic or tonal sound because of improperly sized valves, loudspeaker annunciator use at inappropriate hours, or off-hours maintenance operations (bearing failures, construction/repair operations and truck traffic) have all been sources of noise complaints. These may be considered less than significant with new owners complying with the Lake County Planning Department Use Permit conditions for noise mitigation and adherence to the noise mitigation plans
[End H54]
[Begin H55]Page 6-23, Section 6.4.3 Alternative Three, (paragraph 2, sentence 3) "namely steam stacking" add: well bleeds and steam field maintenance problems. References to "stacking" should be expanded to include all atmospheric releases of untreated steam. Steam stacking presently is a relatively rare event which occurs as result of sudden steam flow rejection and has been of limited occurrence due to lower pipeline pressures and the ability to intertie multiple power plants together. Stacking now is largely avoided by using the interties, the ability of the pipelines to reduce the rate of pressure increase through well steam flow reductions using automated controls.
[End H55]
[Begin H56]Paragraph 4: While the steam field operators have a contract to accept effluent for 25-30 years, the steam supply contracts are likely not of similar duration. The remaining useful life span of many of the power plants will expire prior to this time frame unless there are provisions for maintenance, re-construction or replacement.
[End H56]
[Begin H57]Paragraph 6 (RE: CPUC authority to force sale to particular buyers): While the DEIR explores the potential impacts of a sale to the steam suppliers, it does not explore CPUC or other agency alternatives to assure that the geothermal resource and power production is beneficially operated. The DEIR should explore the impact of classifying the Geysers Power Plant as a "stranded asset" as well as additional details regarding the viability of promoting or subsidizing "green power".
[End H57]
[Begin H58]Attachment C, Page C-1, 1.1 Level of Operation. While the price of steam is a factor in the higher availability of the Lake County power plants, it should also be noted that these Units are of a more advanced design than most of the other PG&E Geysers plants, the steam has significantly lower H2S and corrosive content and the steam supplier has expended considerable capital to maintain production capabilities and improve steam production and electrical generation efficiencies.
[End H58]
[Begin H59]Page C-7 (Paragraph 1); Steam is supplied by the geothermal wells utilizing the underground reservoir pressure and is not "pumped". "Transport" would be a more appropriate term.
[End H59]
[Begin H60]Page C-8 Remedial Actions to Maintain Steam Supplies; Load cycling increases maintenance costs and necessity to re-drill or perform additional well construction. These activities all have increased emissions or increase the potential for emissions and should be minimized to the extent practical and feasible. This should be addressed and mitigation proposed.
[End H60
[Begin H61]Page C-10 Historic and Forecasted Generation, Table C-1. Insight as to why PG&E’s actual generation is significantly lower than available generation since 1995 may be helpful in determining how fuel pricing and contracts affect power plant operations.
[End H61]
[Begin H62]Page C-11, Section 1.4.1, Must Run Designations. Should be modified for the Geysers power plant to favor the efficient use of the resource and to minimize air quality impacts. This unique resource should be removed from the "competitive market" if necessary for preservation.
[End H62]
[Begin H63]Page C-24, Choices Facing Single Power Plant Operator. Page 25 describes the probable certainty of a single plant operator shutting down operations during periods of abundant hydro power, low energy demands and low pricing. This discussion appears to address combustion units and not geothermal, however a complete shut down of the geothermal plant may have unacceptable consequences to the steam field and air quality. A alternate scenario of hydro curtailment is a low load cycling operation which increases stress on components and has higher associated maintenance costs and potential air quality impacts due to breakdown emissions. Power plant cycling from a shut down situation is a less efficient use of the resource and has a much higher excess emissions potential due to equipment failures (unit trips) during plant start up operations. This type of operation should be discouraged and regulated to the extent feasible. This should be discussed and mitigation proposed.
[End H63]
[Begin H64]Page C-29, Spares and Maintenance Policies. This discussion outlines the negative impact on maintenance and spares availability due to price structuring of deregulation. Deferred maintenance and equipment failure is represented as having an increased profit incentive to the portfolio holder of a number of various types of power plant facilities. Equipment failures, start ups and shut downs all typically have associated excess air emissions. For geothermal plants, the emissions can be significant and unscheduled outages also can have severe consequences on the steam suppliers equipment and the geothermal reservoir. These should be discussed with mitigation recommendations.
[End H64]
[Begin H65]Page C-33, Section 3.2.4 Geothermal Steam Supply Contracts. The steam supply contracts have historically impacted air emissions due to a variety of reasons. Where contracts were tied to electrical production there was little incentive for the efficient utilization of steam resources, often to the detriment of air quality where there is no other purchaser available for the steam and the steam flow cannot be fully curtailed because of the potential for well damage. It would appear to be in the best public interest to manage the steam resource for the most efficient utilization of this unique, environmentally superior commodity.
[End H65]
[Begin H66]Page C-34, Section 3.3 The Influence of Must-Run Status on Operations. In order to minimize air emissions associated with cycling, excessive startups or shutdowns and consequent impacts on the steam fields causing well bleeds and/or maintenance related breakdowns, the Geysers Power Plants should be required to maintain a minimum sustaining level of availability and operation. This may be accomplished under a specific must run agreement or other similar regulatory requirement crafted to address these issues. We believe that this type of agreement or approach should be included in the mitigation required for this project. The issue would not be startup costs as much as the cost to the steam supplier and environment of having to shut down. This is missed and needs to be assessed.
[End H66]
[Begin H67]Page 36, (Paragraph 1, footnote 71). Under CPUC D.97-04-042 would the new owner of the older Geysers units have the ability to retire the units, recover associated stranded assets and re-power or construct new replacement units?
[End H67]
[Begin H68]Page D-5, NOP, Environmental Effects. (Bottom of page, paraphrased) The sale of the Geysers Plant could have an effect on the environment, which might be significant, if the sale causes changes such as: the amount or pattern of generation; maintenance practices; etc. (among others). The DEIR concludes that the pattern of generation and maintenance practices may change. The analysis included scenarios which considered a operating capacity range of -9% to +16% from the a 1999 baseline. The air emissions evaluation described more variation with up to a 40% increase, however the analysis did not include emissions from the steam wells or steam field maintenance associated with changes in plant operations. The cumulative impact is believed significant, given that a malfunction at a single plant is capable of causing an exceed of the AAQS and although none is offered, mitigation should be required.
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[Begin H69]Page G-5, Footnote 10. The model heat rate utilized 10,000 Btu/kWh instead of the more technically correct 22,000 Btu/kWh. The footnote stated that this did not affect the total potential generation nor economic dispatch position of individual plants. The reference is in the context of emissions and we fail to understand how a factor of 2.2 is essentially the same value unless the notations in the footnote are incorrect.
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[Begin H70]Page G-7, 2.3 Analytical Maximum Generation, 2.3.1 Procedures, (last paragraph). Typo: Geysers geothermal plants (nos. 13 and 16) supplied by Calpine wells; not Calpine wells (Nos. 13 and 16).
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[Begin H71]Tables G-1 through G-17; Apparent program or program input error for geothermal units. Power plants #13 and #16 are shown with identical capacities, similar generation and capacity factors and share a similar steam resource yet the H2S emissions of Unit #13 is approximately a factor of (6) higher. The H2S values reported in Table G-1 are 28 tons per year and 5 tons per year for Units #13 and #16 respectively. H2S emissions are limited by permit at Unit #13 to 9.47 lb/hr and at Unit #16 to 5 lb/hr. Actual emissions as tested at either unit are similar and typically less than 2 lb/hr (approx. 1.5 - 4 tons per year for each unit), see Exhibit A. The Title V applications (referenced as the source of input data) cite annual emissions at Unit #13 as 14.4 tpy and Unit #16 at 6.2 tpy (total 20.6 tpy). Table 4.5-27 lists 38 tpy for existing and 33 tpy as the 1999 baseline (Table G-1 total for both units is listed as 31 tpy). We also note that the ROG emissions factor (0.01#/Mwh) is the same for all units, however the NC gas concentration (source of ROG) is highly variable on a unit by unit basis. The Appendix G Tables are unclear as to the basis for the underlying emission factors and should be clearly identified.
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