Cosumnes power plant (01-afc-19) data response, set 1A

Insert Figure T&T-73

On page 2 of the Cosumnes Power Plant Transmission System Impact Study (SIS), it states that “the proposed Roseville and Colusa generation projects were not included”. The Colusa Power Plant and the Roseville Power Plant are proposed to be online/operational by the second quarter 2002 and the fourth quarter 2004, respectively. The Cosumnes Power Plant is proposed to be online during the first quarter of 2005 for Phase I and by first quarter 2008 for Phase II. Staff needs additional documentation and information regarding the System Impact Study for the year 2007 and proposed mitigation measures in order to prepare the Staff Assessment for the Cosumnes Power Plant.

86. 
    Please include the Colusa and Roseville projects in the SIS. Analyze the system impact with and without the project during peak and off-peak system conditions, which will demonstrate conformance or non-conformance with the WSCC and NERC reliability and planning criteria with the following provisions:
    

1. 
   Identify major assumptions in the base cases including imports to the system, major generation and load changes in the system and queue generation.
   
2. 
   Analyze system for N-0, important N-1 and critical N-2 contingency conditions and provide a list of criteria violations in a table showing the loadings before and after adding the new generation.
   
3. 
   Provide a list of contingencies evaluated for each study.
   
4. 
   Provide power flow diagrams (MW, % loading & per unit voltage) for base cases with and without the project. Power flow diagrams must also be provided for all N-0, N-1 and N-2 studies where overloads or voltage violations appear.
   
5. 
   List mitigation measures considered and those selected for all criteria violations.
   
6. 
   Provide electronic copies of *.sav and *.drw PSLF files.
   

Staff will need to make use of the Applicant’s figures presented in the AFC and supplemental filings.

87. 
    Please provide three sets of electronic files on CDs of the following figures or their revisions: 1.1-2, 1.1-3, 1.1-4, 1.1-5, 2.2-2, 2.2-3, and all figures contained in the Visual Resources Section of the AFC.
    

88. 
    Please provide three sets of electronic files on CDs of the revisions to existing figures and new figures as requested in the following Data Requests.
    

Natural gas for the facility would be delivered by a 26-mile pipeline, extending west and then north from the project site to the Carson Ice-Gen Facility. The pipeline route would pass through areas that are characterized as urban residential, rural residential, light industry, agriculture, and open space (AFC p. 8.11-3).

89. 
    Please explain whether or not any aboveground facilities would be required for the gas pipeline including pump stations and/or valves. If so, please identify their locations and describe the facility characteristics including dimensions.
    

90. 
    Please identify the number of residences that would have views of the pipeline route during construction and the proximity of those residences to the route.
    
    Response: There are approximately 528 residences located along the 26-mile pipeline that are within 500 feet of the pipeline alignment. It is likely that fewer than the 528 residences would have a view of pipeline construction because of the distance of the residence to the pipeline, the elevation of residences relative to the pipeline, the orientation of the residence relative to the pipeline, weather conditions, and whether there is vegetation, fencing, or other structures that would obstruct views from the residence.
    
91. 
    For a typical pipeline construction spread, please describe the construction equipment to be used, the length of a typical spread, and the amount of time a typical spread would be visible at any one location along the route.
    

• 
  Backfilling equipment (bulldozer, backhoe, etc.)
  
• 
  Boom trucks (for lifting pipe)
  
• 
  Excavation equipment (shovel, clamshell digger, backhoe, etc.)
  
• 
  Material Delivery trucks (dump, flat bed, etc.)
  
• 
  Welding Trucks
  
• 
  Inspection Vehicles
  

In traffic areas the spread will be less than 500 feet, and in rural or agricultural areas the spread will depend on safety and construction efficiency. The exception is if County or City agencies request greater lengths to be used to accelerate the project schedule.

Water for the proposed project would be obtained from an existing pipeline from the Folsom-South Canal (AFC p. 8.11-7) and would not require off-site pipeline construction. However, a package water treatment plant would be required to treat the water from the canal (AFC p. 1-1).

92. 
    Please identify the location of the package water treatment plant and describe its visual character including physical dimensions.
    

As noted in the AFC (p. 8.11-1), the proposed project site is located immediately south of the Ranch Seco Power Plant.

93. 
    Please identify the height of the existing transmission towers that would be paralleled by the proposed transmission towers. The referenced towers are visible in the existing conditions photograph for KOP 1, which is presented in the AFC as Figure 8.11-2a.
    

Figure 2.2-2 provides elevation views of the proposed project but does not show structure heights except for the HRSG stacks (though structure heights are provided in a data adequacy response).

94. 
    Please revise Figure 2.2-2 to specify structure heights.
    

Four key observation points (KOPs) were established in order to evaluate both the visual setting and the potential for project-induced visual impacts. Photographs were obtained at each KOP and presented along with visual simulations of the proposed project. In order to accurately represent the views that would be experienced at each KOP, staff considers 18 inches to be an appropriate reading/viewing distance for all KOP images. However, the images presented (setting photographs as well as simulations) are presented at less than life-size scale when viewed at the 18-inch reading/viewing distance. Although reading/viewing distances of 12 and 13 inches are specified for the images presented in the AFC, the images are still approximately 10 to 15 percent undersized based on field verification. The presentation of images at a reduced scale understates the prominence of visible landscape features as well as potential visual impacts.

95. 
    Please re-scale the setting and simulation images for KOPs 1 and 2 to achieve life-size scale when viewed at a standard reading/viewing distance of 18 inches. If re-scaling results in substantial degradation of the image, please provide new high resolution setting and simulation images at life-size scale. After obtaining appropriately scaled images, please provide five photocopies of high quality 11”x17” color images of the existing views and simulations.
    
    Response: This question will be responded to on February 4, 2002.
    

Figure 8.11-2b provides a simulation of the proposed project as viewed from KOP 1. However the simulation shows the previously proposed H-frame transmission structures and not the currently proposed tubular style.

96. 
    Please revise Figures 8.11-2b (KOP 1) and 8.11-3b (KOP 2) to show the currently proposed tubular transmission towers.
    

97. 
    Please specify the heights of the currently proposed tubular transmission towers.
    

Section 8.11.4.3.2 addresses the project landscaping that is to be installed along the southern perimeter of the project site but provides minimal description of the landscaping including the species to be planted and times to maturity. Figure 8.11-2b provides a simulation of the proposed landscaping at 20 years from KOP 1. The landscaping along the southern perimeter of the site is ineffective in screening project structures from nearby residential views. Also, it should be noted that staff considers any project-induced visual impact extending beyond five years after completion of project construction to be a long-term visual impact.

98. 
    Please provide additional detail about the landscape plan including species to be planted and times to maturity.
    

99. 
    Please provide a revised landscape plan to include landscape screening along the western perimeter of the site.
    

• 
  Re-alignment of an ephemeral swale is proposed along the outer western edge of the site. Landscaping in or along the restored ephemeral swale is inconsistent with Sacramento County General Plan Conservation Element CO-112 that requires preserving the ecological integrity of the preexisting stream and CO-117 that requires a buffer zone between the stream and any existing or planned riparian or wetland vegetation. Planting trees or shrubs in this zone could interfere with the biological preservation and conformance to County Ordinance.
  
• 
  The plant’s western perimeter is an electrical switchyard that is approximately 50 feet east of existing transmission towers and power lines. The area underneath the transmission lines and to the sides must comply with CPUC GO-95, “Rules for Overhead Electric Line Construction”. Compliance with these orders and good engineering practice would be inconsistent with planting trees or shrubs that could present a fire hazard or interfere with safe operation of electrical features.
  
• 
  The County of Sacramento Planning and Community Development Department reviewed consistency of the project, including landscaping plans, and reported their findings to the Sacramento County Board of Supervisors on December 5, 2001. The proposed landscaping along the southern perimeter was sufficient, upon review of the actual landscaping plans, to comply with County Ordinances.
  

100. 
     For KOPs 1 and 2, please provide five photocopies of high-resolution 11”x17” color images of life-size scale simulations of the revised landscape screening vegetation along the western perimeter at five years of growth and 20 years of growth.
     

The AFC discusses the need for project night lighting and the controls that would be utilized to minimize the visibility of night lighting (AFC p. 8.11-9). The AFC also states that the current lighting levels at the Rancho Seco Power Plant are approximately 75 percent of the operating plant lighting level. However, the discussion of lighting does not describe the extent to which existing night lighting is visible from nearby viewing locations or the extent to which proposed project night lighting would be visible to those same locations.

101. 
     Please describe existing visible night lighting at the project site and the Rancho Seco Power Plant.
     
     Response: There is currently no night lighting at the project site. The project site is currently undeveloped. Night lighting at the Rancho Seco Plant (RSP) site consists of red flashing lights atop the two 426-foot-high cooling towers, red non-flashing lights on the cooling towers at heights of approximately 180 feet and 270 feet, and a combination of orange-colored and white lights on poles and mounted on buildings/facilities. A faint glow, from the lighting at the plant, can be seen in the sky above the Rancho Seco Power Plant. There is also a street light at the nearest utility pole at the driveway to the trailer located closest to the plant.
     
102. 
     For KOPs 1 and 2, please provide photocopies of high-resolution 11”x17” color images of life-size scale existing nighttime setting photographs to show existing night lighting levels at the project site and Rancho Seco Power Plant.
     
     Response: See Figures 8.11-2c and 8.11-3c showing nighttime views of the Rancho Seco Power Plant from KOPs 1 and 2, respectively.
     
103. 
     Please describe the extent to which night lighting during project operation would be visible from each KOP. Also, please describe the visibility of project components (including exhaust stacks and vapor plumes) due to illumination from: a) existing ambient lighting and b) the combination of existing ambient lighting and proposed project lighting.
     
     Response: Viewers at KOP 1, because it is the closest to the project site, would have the most direct, and closest, nighttime view of the CPP project. Viewers at KOPs 2 and 3 would also be able to see the CPP facility with night lighting, but at a greater distance, and the clarity of each individual project feature would diminish with distance. This diminishing clarity is demonstrated in the daytime simulations that were prepared for KOPs 1, 2, and 3 (Figures 8.11-2b, 3b, and 4b). At night, it is expected that silhouettes of these facilities (if they have mounted lights or are near light poles) would be partially visible, but that unlit facilities would essentially disappear in the darkness.

     Because the lights would be directed downward, illumination of visible plumes from mounted lights or light poles is expected to be minimal. It is, however, expected that CPP project lighting may produce a faint nighttime sky glow during periods of high humidity, and the plumes could be visible in the sky glow. The expected nighttime sky glow would be similar to what is seen at RSP, but to a lesser degree, because of the smaller plant size, the use of directional lighting, and the use of switches and timers for the lights.

     Nighttime views of the CPP project from KOP 4 would be minimal, as is demonstrated by what would be seen during the daytime in Figure 8.11-5b. It is possible that a faint sky glow would be visible from KOP 4 (the picnic area at Rancho Seco Park); however, the park closes at dusk and the gate is locked, so viewers from outside the park would not have nighttime access to the picnic area after dark. Recreationists camping at the park would still have access to the picnic area after dark; however, the picnic area is not lit at night, and in fact, the area is very dark, so recreationists would not likely be at the picnic area to see the CPP project’s sky glow from this KOP.

     Because the RSP facilities are located approximately 1,000 feet north of the project site, existing RSP lighting is not expected to significantly illuminate CPP project facilities, nor would it significantly combine with CPP project lighting to illuminate project components.

     
     
104. 
     Please identify whether or not facility stack lighting would be required and if so, by which agency or requirement, and in what manner.
     
     Response: The agency determining the requirement for lighting the facility stack is the Federal Aviation Administration (FAA). The FAA has indicated that stack lighting is not required on structures less that 200 feet tall that are more than 3 nautical miles from an airport (Karen McDonald, pers. comm., 2001). (See also, Data Response #82). Sacramento County would not require stack lighting for the project, but would defer to the FAA for its lighting requirement (Tricia Stevens, pers. comm., 2001).
     
105. 
     Please describe night lighting to be used during project construction.
     
     Response: The vast majority of project construction would occur during the daytime. Nighttime construction may, however, occur if requested by the County for pipeline trenching in/near roadways for traffic management purposes (to avoid traffic congestion), and for horizontal directional drilling (HDD) of the pipeline, which, once started, would continue 24 hours a day until that drill is completed.

     During this nighttime construction, the District would use standard white construction lights that would be approximately 6 to 8 feet tall and would be directed toward the construction site and the particular construction activity, rather than directed off-site.

     
     

The AFC discusses the formation of water vapor plumes associated with the proposed project (AFC pp. 5.12-15 and 13) but does not identify whether or not there are any existing sources of plumes in the immediate project vicinity or region.

106. 
     Please verify if there are any other plume sources within five miles of the proposed project site. If plume sources exist, then please describe them and provide a map with the plume locations indicated.
     

AFC Section 8.11.5.3.3, pp. 8.11-12,13, states that the plume frequency of the project would be minimal. However, no further information is given to substantiate that claim. Staff requires cooling tower and HRSG operating data to model the plume frequency and plume dimensions to determine the potential significance of the project’s visible water vapor plumes.

107. 
     Please complete the following table of operating parameters for the cooling tower:
     
     Table 1
     

Parameter	Value
Maximum Design Inlet Air Flow Rate (kg/s)	7.2
Maximum Heat Rejection Rate (MW)	335.6
Design Liquid to Gas (L/G) Mass Ratio	1.10

108. 
     Please provide, at a minimum, the operating exhaust temperatures and exhaust flows from the cooling tower that correspond to the following ambient conditions (a similar set of ambient conditions may be substituted for the values specified as long as they represent the range of ambient conditions expected at the site). The values presented should correspond to maximum anticipated heat rejection at the specified ambient conditions.
     
     Table 2
     

109. 
     For staff to conduct CSVP modeling of the plume abated HRSG exhaust, please provide, at a minimum, HRSG exhaust parameter data to complete the following table (a similar set of ambient conditions may be substituted for the values specified as long as they represent the range of ambient conditions expected at the site). The values must correspond to full turbine load operating conditions at the specified ambient conditions.
     
     Table 3
     

110. 
     Please identify the minimum ambient temperature where inlet air fogging will be used.
     

Insert Figures 8.11-2c and 8.11-3c

According to the AFC, the proposed Cosumnes Power Project (CPP) will require approximately 8,000 acre-feet of water in a typical year with peak annual demands as high as 9,000 acre-feet per year. During normal operation, 97 percent of the total water requirements for the CPP are for cooling water. The Sacramento Municipal Utility District (SMUD) intends to use high quality American River water from the Folsom South Canal for cooling purposes. Such use of fresh water for cooling purposes is discouraged in accordance with the California Water Code.

Alternatives to wet cooling and other sources of water supply must be more fully evaluated. The AFC provides only a limited discussion of alternatives (AFC pages 7-7 and 7-8) relating to State Water Resources Control Board’s Resolution 75-58. The use of inland wastewater from the Galt Wastewater Treatment Plant (GWTP) and the Sacramento Regional Wastewater Treatment Plant (SRWTP) were rejected in the AFC as environmentally unacceptable and economically unsound but there is no information provided as to what the actual environmental impacts and costs would be, and why these were considered prohibitive. State Water Resources Control Board (SWRCB) Policy 75-58 requires studies to include analysis of cost and benefits of alternative supplies (that are reasonably available) and cooling alternatives.
The applicant’s proposed use of wet cooling with 3 to 10 cycles of concentration results in significantly greater consumption of a high quality surface water and effluent discharge than comparable power generating facilities. These impacts can be reduced with higher cooling tower concentration cycles and/or other water conservation alternatives. A more thorough assessment of alternatives is needed. In addition, the applicant does not yet have a U.S. Bureau of Reclamation (USBR) contract for Central Valley Project (CVP) water after 2012, and the USBR is currently preparing an Environmental Impact Statement on the use and allocation of American River water, and thus availability is not yet assured for the life of CPP.
Surface water requirements can be reduced with the use of reclaimed water, as well as with the use of cooling alternatives. An assessment of alternatives, as required by California Water Code Section 13550 et seq. and SWRCB Policy 75-58, will help show the most effective method to reduce make-up water requirements.