January 5, 2012 

Mr. Gerardo Rios 

Chief, Permits Office 

U.S. EPA Region 9 

75 Hawthorne Street 

San Francisco, CA 94105 

Subject: Pio Pico Energy Center PSD Permit Application 

 Modeling Questions 

 

 

Dear Mr. Rios: 

As requested by EPA in the December 9, 2011 meeting between representatives of EPA 

and Pio Pico Energy Center, LLC (Applicant), we are herein submitting additional 

information on behalf of Applicant. Specifically, EPA requested additional analysis and 

information to support the modeling performed for the Pio Pico PSD Permit Application. 

It should be noted that Applicant submitted the proposed modeling protocol for the Pio 

Pico Energy Center (Project) to EPA on December 1, 2010, with a request for review and 

comment, consistent with EPA’s policy encouraging early consultation on modeling 

issues.1

 EPA did not respond to Applicant’s request. In the absence of any questions or 

concern expressed by EPA regarding the protocol, the Applicant proceeded with 

modeling and analysis consistent with the protocol, and has expended considerable time 

and effort in reliance on EPA’s tacit approval. 

Data Substitution 

Comment: Provide tables showing the measured data (prior to data substitution). 

Response: The requested information has been prepared by the San Diego Air Pollution 

Control District (District), and is included on the enclosed disk. 

Meteorological Data

 

Comment: Justify the use of Otay Mesa meteorological data to characterize conditions 

in the project area. 

 

1

 Appendix W, Section 10.2.1: “[e]very effort should be made by the Regional Office to meet with all 

parties involved in a SIP revision or a PSD permit application prior to the start of any work on such a 

project. During this meeting, a protocol should be established between the preparing and reviewing parties 

to define the procedures to be followed, the data to be collected, the model to be used, and the analysis of 

the source and concentration data.” 

sierra 

research

1801 J Street 

Sacramento, CA 95811 

Tel: (916) 444-6666 

Fax: (916) 444-8373

Ann Arbor, MI 

Tel: (734) 761-6666 

Fax: (734) 761-6755 
Gerardo Rios -2- January 5, 2012 

Response: The following discussion is based on criteria described in Section 3.1 

(Representativeness) in EPA’s Meteorological Monitoring Guidance for Regulatory 

Modeling Applications (February 2000). 

The guidance states that “Representativeness has been defined as ‘the extent to which a 

set of measurements taken in a space-time domain reflects the actual conditions in the 

same or different space-time domain taken on a scale appropriate for a specific 

application.’” The guidance indicates that “a quantitative method does not exist for 

determining representativeness absolutely.” There are no generally accepted analytical or 

statistical techniques to determine representativeness of meteorological data or 

monitoring sites. 

In general, for use in air quality modeling applications, meteorological data should be 

representative of conditions affecting the transport and dispersion of pollutants in the 

“area of interest” as determined by the locations of the sources and receptors being 

modeled. For this project, the “area of interest” includes the project site and the 

significant impact area (the area where screening modeling predicts project impact of any 

pollutant above Significant Impact Levels). 

In steady-state modeling applications, one typically focuses on the meteorological 

conditions at the release height of the source or sources, or the plume height in the case of 

buoyant sources. Representativeness for steady-state modeling applications must 

necessarily be assessed in concert with the steady-state assumption that meteorological 

conditions are constant within the space-time domain of the application; as typically 

applied, measurements for a single location, somewhere near the source, are assumed to 

apply, without change, at all points in the modeling domain. 

As can be seen in Figure 1, the Project site, the Otay Mesa monitoring site, and Brown 

Airfield, from whose meteorological monitoring station the few substituted 

meteorological data were obtained, are all situated on the same flat mesa within three 

miles of each other. The Otay Mesa monitoring site is less than two miles from the 

project site. Air flow over all three locations is sufficiently identical to consider 

meteorological data monitored at the International Border Crossing to represent the 

meteorological conditions at the project site (see wind roses for Otay Mesa and Brown 

Airfield monitoring data in Figures 2 and 3, respectively). Wind speeds at the Otay Mesa 

monitoring site are somewhat slower than those at Brown Airfield, leading to more 

conservative air quality concentrations computed by AERMOD from Project emissions. 

Consistency would call for site selection criteria consistent with the steady-state 

assumption; i.e., to the extent possible, sites should perhaps be selected such that factors 

that cause spatial variations in meteorological conditions are invariant over the spatial 

domain of the application, whatever that might be. Such factors would include surface 

characteristics such as ground cover, surface roughness, the presence or absence of water 

bodies, etc. Similarly, the representativeness of existing third-party databases should be 

judged, in part, by comparing the surface characteristics in the vicinity of the 

meteorological monitoring site with the surface characteristics that generally describe the 

analysis domain. 
Gerardo Rios -3- January 5, 2012 

Figure 1 

PPEC Project Site and Vicinity 
Gerardo Rios -4- January 5, 2012 

Figure 2 

Wind Rose, Otay Mesa International Border Crossing Meteorological 

Monitoring Station, 2006-2008
Gerardo Rios -5- January 5, 2012 

Figure 3 

Wind Rose, Brown Field Meteorological Monitoring Station, 2006-2008
Gerardo Rios -6- January 5, 2012 

The surface characteristics around the Otay Mesa meteorological station at the 

International Border Crossing and the project site are shown in Table 1. 

Table 1: Otay Mesa Meteorological Station Surface Characteristicsa

Month Sector Alb Bo Zob

1 1 0.18 1.09 0.7 

2 1 0.18 1.09 0.7 

3 1 0.16 0.65 0.7 

4 1 0.16 0.65 0.7 

5 1 0.18 0.70 0.7 

6 1 0.18 0.70 0.7 

7 1 0.18 0.70 0.7 

8 1 0.18 0.70 0.7 

9 1 0.18 0.70 0.7 

10 1 0.18 1.09 0.7 

11 1 0.18 1.09 0.7 

12 1 0.18 1.09 0.7 

 

Sector = 360 degrees, Alb = Albedo, Bo = Bowen Ratio, and Zo = surface roughness. 

 a Used in AERMET for AERMOD Air Dispersion Modeling. b Values adjusted by SDAPCD from the AERSURFACE values of 0.2. 

Table 2: “Area of Interest” Surface Characteristicsa

Month Sector Alb Bo Zo 

1 1 0.17 1.26 0.5 

2 1 0.17 1.26 0.5 

3 1 0.17 0.85 0.5 

4 1 0.17 0.85 0.5 

5 1 0.17 0.76 0.5 

6 1 0.17 0.76 0.5 

7 1 0.17 0.76 0.5 

8 1 0.17 0.76 0.5 

9 1 0.17 0.76 0.5 

10 1 0.17 1.26 0.5 

11 1 0.17 1.26 0.5 

12 1 0.17 1.26 0.5 

 

Sector = 360 degrees, Alb = Albedo, Bo = Bowen Ratio, and Zo = surface roughness. 

 a Area immediately east of project site. Values generated using AERSURFACE. 

. 
Gerardo Rios -7- January 5, 2012 

The data in Table 1 were developed by the District with guidance methodology described 

in its February 3, 2011 email (see Attachment D), as follows: 

The recommended approach for processing digitized land cover data to determine 

the effective Bowen ratio and Albedo for input to AERMET is to average the 

surface characteristics across a representative domain without any direction or 

distance dependency. The recommended default domain is a 10km by 10km region 

centered on the measurement site. A domain representative of the application site 

may be more appropriate for some applications, particularly if the majority of 

sources are elevated releases. 

For this project we chose to use the proposed Pio Pico facility location as the 

center of the domain used in determination of the Bowen Ratios and Albedos on a 

monthly basis since the proposed facility is comprised of elevated sources. 

 AERSURFACE was used for this purpose. We modify the seasonal categories for 

San Diego County for input to the AERSURFACE program as follows: 

o Transitional Spring: March and April 

o Midsummer: May, June, July, August, September 

o Autumn with unharvested cropland: October, November, 

December, January, February 

Since AERSUFACE currently uses a Land Use data base from 1992, and does not 

take buildings in to account, we then modified the Surface Roughness value 

determined for the actual Meteorological tower location (SDAPCD Otay 

monitoring station), which is located approximately 1.8 miles SW of the proposed 

facility site. The value obtained using AERSURFACE was approximately 0.2. 

 We replaced this with a Surface Roughness value of 0.7 based on a review of 

aerial photos for the area. We feel that this better represents the vicinity of the 

Meteorological tower as a light industrial and residential area that includes 

northern Mexico and the U.S border area.2

For comparison, average surface characteristics were developed using AERSURFACE 

for the 10 km by 10 km analysis domain with its western border near the project site, and 

its southeast corner close to the U.S.-Mexico border (see Figure 4). This domain covers 

most of the significant impact area, including the areas with the highest impacts. It 

therefore best represents the “area of interest” for the project. The results are shown in 

Table 2. 

 

2

 Email from Ralph DeSiena (District) to Eric Walther (Sierra Research), February 3, 2011. 
Gerardo Rios -8- January 5, 2012 

Figure 4 

Location of Domain Representing Area of Interest 

for Surface Characteristic Analysis

 
Gerardo Rios -9- January 5, 2012 

Surface characteristics affect modeling results.3

 As shown in Tables 1 and 2, the albedos 

for the two domains are very similar (0.16 - 0.18 for the Otay Mesa meteorological 

station, and 0.17 for the area of interest). The Bowen Ratios in Table 2 are consistently 

slightly higher than the Bowen Ratios in Table 1, reflecting a small difference between 

surface moisture present in the light industrial and residential area surrounding the Otay 

Mesa Station and in the relatively uniform sparse desert ground cover/vegetation that 

characterizes the area of interest. The higher the Bowen Ratio, the dryer the ground 

surface, and the less latent heat transfer contributes to overall heat flux from convective 

turbulence (i.e., the more sensible heat transfer contributes to overall heat flux from 

convective turbulence). Increasing this surface characteristic causes a small increase in 

the calculated ground-level concentration.4 The surface roughness difference between 

0.7 and 0.5 meters in the two tables, respectively, is similar, with both values determined 

to be in the same Category 2 (medium roughness) according to the Texas Commission on 

Environmental Quality.5 For 35 meter stacks, the higher the surface roughness, the 

higher the concentration. 

In summary, the albedo for the meteorological station is essentially the same for the area 

of interest; the Bowen Ratios at the meteorological station are consistently lower than for 

the area of interest, which would tend to lower maximum modeled concentrations; and 

the surface roughness is higher at the meteorological station than for the area of interest, 

which would tend to increase modeled concentrations. Overall, comparison of the 

surface characteristics at the meteorological monitoring site with the surface 

characteristics in the area of interest supports the use of the Otay Mesa border 

station meteorological data as representative. 

Using EPA guidance as a basis, the factors listed below were considered in the 

determination of representativeness: 

 In general, the representativeness of the meteorological data used in an air 

quality modeling analysis is dependent on the proximity of the meteorological 

monitoring site to the “area-of-interest.” As previously indicated, the source of 

the meteorological data used in this analysis is two miles from the project site 

away with no intervening structures, hills, or water bodies that might significantly 

affect meteorological conditions. Factor weighs in favor of considering the 

data representative.

 Spatial representativeness of the data will almost always be adversely affected 

(degraded) by increasing the distance between the sources and receptors 

(increasing the size of the area-of-interest). This is inevitable in a steady-state 

 

3

 The qualitative description of the effects of surface characteristics on modeling results are from T.G. 

Grosch and R.F. Lee, “Sensitivity of the AERMOD Air Quality Model to the Selection of Land Use 

Parameters,” http://www.environmentalexpert.com/Files%5C20658%5Carticles%5C4842%5Ctp_wessex99.pdf 

4

 Grosch and Lee. Ibid.

5

 Texas Commission on Environmental Quality, “AERMOD Training,”

http://www.cabq.gov/airquality/pdf/tceqsfcroughnessguidance.pdf, accessed December 22, 2011.
Gerardo Rios -10- January 5, 2012 

model, and provides no basis for distinguishing between one set of data and 

another. Factor is neutral with regard to considering the data representative.

 Although proximity of the meteorological monitoring site is an important factor, 

representativeness is not simply a function of distance. In some instances, even 

though meteorological data are acquired at the location of the pollutant source, 

they may not correctly characterize the important atmospheric dispersion 

conditions; e.g., dispersion conditions affecting sources located on the coast are 

strongly affected by off-shore air/sea boundary conditions - data collected at the 

source would not always reflect these conditions. The source of meteorological 

data, the project site, and the area-of-interest are all located well inland, in close 

proximity to each other, and have surface characteristics that are similar to each 

other. Factor weighs in favor of considering the data representative.

 Representativeness is a function of the height of the measurement. For example, 

one can expect more site-to-site variability in measurements taken close to the 

surface compared to measurements taken aloft. As a consequence, upper-air 

measurements are generally representative of much larger spatial domains then 

are surface measurements. The meteorological sensors at the Otay Mesa 

monitoring station are located at the 10 meter (32.8 feet) standard height. The 

sensors therefore provide wind speed, wind direction, and temperatures that 

appropriately characterize a realistic boundary layer near the monitoring station 

and throughout the analysis domain that includes the Project site. Factor weighs 

in favor of considering the data representative.

 Factors that should be considered in selecting a monitoring site in complex 

terrain include: the aspect ratio and slope of the terrain, the ratios of terrain 

height to stack height and plume height, the distance of the source from the 

terrain feature, and the effects of terrain features on meteorological conditions, 

especially wind speed and wind direction. The Project site is somewhat closer to 

the San Ysidro Mountains to the east than is the Otay Mesa monitoring station. 

The San Ysidro Mountains have maximum elevations around 2,000 feet. The 

wind roses in Figures 2 and 3 and the wind roses for Chula Vista and El Cajon 

contained included as Figures 1 and 2, respectively, in our December 1, 2011 

letter all show the dominance of the westerly sea breezes throughout this region 

west of the mountains. The fact that the mountains are downwind of both the 

Project site and the monitoring station almost all of the time assures that effects of 

the elevated terrain in the mountains on the monitored values of wind speed and 

direction are likely to be similarly minimal for both sites. Factor weighs in favor 

of considering the data representative.

In summary, consideration of the factors listed in EPA guidance on determination of the 

representativeness of meteorological data results in the conclusion that the Otay Mesa 

data are adequately representative of the area of interest for this Project. Furthermore, 

any objections that might be raised concerning the Otay Mesa data would be equally 

applicable to data that might be collected onsite. Therefore, there is no basis for 

requiring collection of onsite meteorological data. 
Gerardo Rios -11- January 5, 2012 

In-Stack NO2/NOx Ratio 

Comment: Provide the documents that were used to derive the in-stack NO2NOx ratios 

for the NO2 modeling analysis.

Response: At the direction of the District, the NO2/NOx ratios used for PPEC in the 

dispersion modeling were revised to 13% during normal operations and 24% during 

startup and commissioning. The District justified those levels in an email6 to the 

applicant as follows: 

The tentative recommendation for normal operations is based on source tests of 

four natural-gas-fired LM6000PC SPRINT turbines equipped with water 

injection, SCR, and oxidation catalysts. Preliminarily, these appear to be the 

closest analogue to the LMS100 as proposed for Pio Pico (i.e., aeroderivative, 

simple cycle, diffusion flame combustors, same NOx controls, oxidation catalysts, 

and interstage cooling—albeit with water injection for the SPRINTs). The value 

is an average over the four turbines (rounded up) of the average NO2/NOx ratio 

for each turbine. The average NO2/NOx ratios for the four turbines were .0393 

(2 tests), .0603 (2 tests), 0.185 (1 test), and 0.205 (1 test), respectively. 

For situations when the SCR is not operating, the tentative ratio is based on 

source tests of 11 natural-gas-fired GE Frame 5 turbines. These turbines all have 

water injection but no other NOx controls and no oxidation catalyst. The 

NO2/NOx ratio for these turbines ranges from about 0.18 to 0.285 (averaged over 

7-10 source tests of each turbine). 

The source tests were all at greater than 80% load. 

The Pacific Recovery NO2/NOx ratio of 75% was taken from source test data for the 

facility. The data were provided by the District to be used for this analysis (see 

Attachment B). Over four test runs, average NO2/NOx ratios ranged from 55% to 75%. 

For the cumulative impact analysis, the applicant selected the most conservative average 

value to characterize this source. 

The Otay Mesa NO2/NOx ratio of 5% was taken from source test data for the Otay Mesa 

facility. The data were provided by the District to be used for this analysis (see 

Attachment C). The NO2/NOx ratio ranged from 4% to 6% with the duct burners, and 

4% to 7% without duct burners. For the cumulative impact analysis, the applicant 

selected a round number within the range. 

The NO2/NOx ratios for the small Calpeak Boarder and Larkspur units (all 10%) were 

based on a conservative interpretation of data provided by the District (see 

Attachment C). 

 

6

 See the December 23, 2010 email from Steve Moore to Steve Hill provided in Attachment A. 
Gerardo Rios -12- January 5, 2012 

PM BACT for Turbines 

Comment: Provide the data from the Panoche Energy Center project used to 

develop the proposed turbine PM BACT emission level of 5.5 lb/hr. 

Response: The Panoche Energy Center source test data are summarized in Table 3. 

Please note that these few source tests are not sufficient to demonstrate that the 

measured emission rates are achievable under all conditions and for the lifetime of the 

turbines. Furthermore, the test method used to measure PM is not very accurate at the 

low levels being measured; there is considerable variability in the results. For these 

reasons, the applicant has proposed a compliance level that takes into account (a) the 

vendor guarantee; (b) the emission levels demonstrated in the source tests; (c) 

reasonable variability in performance that can be expected over the lifetime of a wellmaintained unit; and (d) the variability inherent in the source test methodology. 

Taking all of the above into account, test results provide sufficient support for the 

Applicant to determine that it can comply with a 5.5 lb/hr emission limit, which is 

equivalent to 0.0065 lb/MMBtu measured at or near peak turbine load. 

Source test reports and/or summaries are included on the enclosed CD. 
Gerardo Rios -13- 

Table 3. Panoche Energy CenterPM Emission Tests Results (lb/MMBtu) 4 x 100 MW GE Model LMS100 combustion turbines 

Date 5/13/2011 5/12/2011 5/11/2011 5/10/2011 5/11/2010 5/12/2010 5/18/2010 5/19/2010 

4/30/09 - 

5/1/09 

Unit 1 2 3 4 1 2 3 4 1 

Unit 

Load 100% 

Run 1 0.00298 0.00402 0.00314 0.00184 0.00279 0.00141 0.00168 0.00249 0.002 Run 2 0.00261 0.00192 0.00420 0.00182 0.00213 0.00107 0.00176 0.00198 0.002 Run 3 0.00167 0.00169 0.00605 0.00185 0.00169 0.00155 0.00149 0.00310 0.004 

Average 0.00242 0.00254 0.00446 0.00184 0.00220 0.00134 0.00164 0.00252 0.003 

2011 2010 2009 Overall 

Average 0.00282 0.00193 0.004 0.003 

Std Deviation 0.00136 0.00060 0.003 0.002 

Relative Std 

Deviation 48% 31% 78% 73% 

Mean plus 2 S.D 0.0055 0.0031 0.0103 0.0072 
GHG BACT for Turbines 

Comment: In Step 4 of the BACT analysis, Applicant made the following statement: 

“A larger-capacity unit would be operated at less than optimum (full) output more 

frequently than a smaller-capacity turbine, and since gas turbine efficiency drops 

rapidly at less than full load, this mode of operation would likely reduce the overall 

efficiency of the combined-cycle units to below that of the proposed simple-cycle gas 

turbines.” Please provide the basis for this claim. 

Response: As shown in Figure 5, turbine efficiency drops rapidly at less than full 

load. A single, high-efficiency combined-cycle unit (such as an F-class unit in a 1x1 

configuration) cannot effectively operate through the broad range of loads that 

multiple simple-cycle units can.7

 Figure 5 compares the efficiency curves for the 

proposed LMS100 configuration with an F-class combined cycle unit (GE S107FB). 

It is important to note that while the LMS100 configuration provides the flexibility to 

operate across the full range of loads between approximately 50 MW and 300 MW, it 

will most likely be dispatched to operate at the more efficient loads of 100 MW, 200 

MW or 300 MW. 

Figure 5 

Turbine Efficiency Curves 

 

7

 As designed, PPEC is capable of providing load-following capability from a minimum of 50 MW up to its 

full capacity of 300 MW. The GE S107FB is limited to a range of approximately 110-280 MW. The 

broader range of response is an important feature of PPEC’s proposal to SDG&E. 

0

2,000

4,000

6,000

8,000

10,000

12,000

0 100,000 200,000 300,000

Net Heat Rate, BTU (HHV)/KW‐hr

Net Power Productions, KW

LMS‐100 (3 turbines)

F‐Class Combined Cycle

1 turbine 2 turbines 3 turbines
If you have any questions regarding this information, please contact the Applicant’s 

representative David Jenkins at (317) 431-1004, or Gary Rubenstein or me at 

(916) 444-6666. 

Sincerely, 

Steve Hill 

cc: John McKinsey, Stoel Rives LLP 

David Jenkins, Apex Power Group 

 Steve Moore, San Diego Air Pollution Control District 

Attachments 

Enclosure: CD 
ATTACHMENT A 

December 23, 2010 Email from Steve Moore to Steve Hill
1

Steve Hill

From: Moore, Steve <Steve.Moore@sdcounty.ca.gov>

Sent: Thursday, December 23, 2010 2:36 PM

To: Steve Hill

Cc: Eric Walther

Subject: RE: Pio Pico NO2/NOx

Follow Up Flag: Follow up

Flag Status: Completed

Expires: Sunday, December 20, 2020 12:00 AM

Steve,

The tentative recommendation for normal operations  is based on source tests of four natural‐gas‐fired LM6000PC

SPRINT turbines equipped with water injection, SCR, and oxidation catalysts.  Preliminarily, these appear to be the

closest analogue to the LMS100 as proposed for Pio Pico (i.e., aeroderivative, simple cycle, diffusion flame combustors,

same NOx controls, oxidation catalysts, and interstage cooling—albeit with water injection for the SPRINTs).  The value is

an average over the four turbines (rounded up) of the average NO2/NOx ratio for each turbine.  The average NO2/NOx

ratios for the four turbines were .0393 (2 tests), .0603 (2 tests), 0.185 (1 test), and 0.205 (1 test), respectively.  

For situations when the SCR is not operating, the tentative ratio is based on source tests of 11 natural‐gas‐fired GE

Frame 5 turbines.  These turbines all have water injection but no other NOx controls and no oxidation catalyst.  The

NO2/NOx ratio for these turbines ranges from about 0.18 to 0.285 (averaged over 7‐10 source tests of each turbine).

The source tests were all at greater than 80% load.

Thanks.

Steven Moore Senior Air Pollution Control Engineer San Diego County Air Pollution Control District 10124 Old Grove Road, San Diego, CA 92131 

858-586-2750 

Celebrating 50 years of air quality progress!

From: Steve Hill [mailto:SHill@sierraresearch.com] 

Sent: Thursday, December 23, 2010 1:48 PM 

To: Moore, Steve; Eric Walther 

Cc: Gary Rubenstein 

Subject: RE: Pio Pico NO2/NOx 

Thank you for the guidance.
2

Can you please provide the justification for using those values?  We need to be able to explain to EPA the basis for any

value that we use.  We can refer to San Joaquin’s published guidance for a ratio of 0.10, but have been unable to find

source test data to support a different value.

‐‐Steve

From: Moore, Steve [mailto:Steve.Moore@sdcounty.ca.gov] 

Sent: Thursday, December 23, 2010 1:16 PM 

To: Steve Hill; Eric Walther 

Subject: Pio Pico NO2/NOx 

Steve & Eric,

For purposes of the AQIA in a submittal of a new or revised application for the Pio Pico Energy Center, the District

tentatively recommends the following in‐stack NO2/NOx ratios for the LMS100 turbine proposed for the project:

Normal Operations: 0.13

Commissioning, Startup, or any other situation when the SCR is not fully operational:  0.24

Please be aware that the District is continuing to investigate this issue and reserves the right to change these tentative

recommendations based on reevaluation of existing information or new information.

Thanks.

Steven Moore Senior Air Pollution Control Engineer San Diego County Air Pollution Control District 10124 Old Grove Road, San Diego, CA 92131 

858-586-2750 

Celebrating 50 years of air quality progress!
ATTACHMENT B 

Pacific Recovery Test Data 
NO2 

Priority PO_NUM ID_NUM DBA EQUIP_DESC M

1 40247-1 6068

Pacific Recovery, Otay Landfill, Eng @1

One Cooper Superior model 16SGTA pre-chamber lean burn piston engine, rated at 2650 bhp at 900 rpm. Fueled with landfill gas from a landfill gas collection system consisting of 62 wells and associated landfill gas venting system which also supplies fuel to engine #2. 

Coo

1 40247-2 6068

Pacific Recovery, Otay Landfill, Eng #2

One Cooper Superior model 16SGTA pre-chamber lean burn piston engine, rated at 2650 bhp at 900 rpm. Fueled with landfill gas from a landfill gas collection system consisting of 62 wells and associated landfill gas venting system which also supplies fuel to engine #1. 

Coo

1 979979-3 6068

Pacific Recovery, Engine #3, Otay Landfill

One Cooper Superior model 16SGTA pre-chamber lean burn piston engine, rated at 2650 bhp at 900 rpm. Fueled with landfill gas from a landfill gas collection system consisting of 62 wells and associated landfill gas venting system which also supplies fuel to engine #1

Coo

1 979979-4 6068

Pacific Recovery, Engine #4, Otay Landfill

One Cooper Superior model 16SGTA pre-chamber lean burn piston engine, rated at 2650 bhp at 900 rpm. Fueled with landfill gas from a landfill gas collection system consisting of 62 wells and associated landfill gas venting system which also supplies fuel to engine #1

Coo

TC = TurbochargedAC = Aftercooled4DR = Timing retarded by 4 degreesDPF Diesel Particulate FilterSCR = Selective Catalytic ReductionOxCat = Oxidation CatalystLB = Lean BurnLFG = Landfill Gas
BHP

Spark 

Ignited 

Engine 

Type Turbocharged Aftercooled Timing

Diesel 

Particulate 

Filter

Add-on 

NOx 

Control

InCombutor 

NOx 

Control

CO/VOC 

Control Fuel No. T

2650 LB — — — — — — — LFG 12650 LB — — — — — — — LFG 8 2650 LB — — — — — — — LFG 2 2650 LB — — — — — — — LFG 3 
Maximum 

NO2/NOx

Minimum 

NO2/Nox

NO2/NOx 

Standard 

Deviation

Average 

Load, %

67.9 5.1 18.13075 97.5%71.2 6.6 20.77605 97.5%78.2 71.5 4.737615 97.4%72.3 33.8 20.08889 95.5%
ATTACHMENT C 

Turbine Test Data
NO2 

Priority ID_NUM M_DBA PO_NUM EQUIP_DESC

1 7630

WILDFLOWER ENERGY LP/LARKSPUR 

976094

ONE (1) GENERAL ELECTRIC 45 MW NOMINALLY RATED MODEL LM 6000 PC SPRINT SIMPLE CYCLE GAS TURBINE WITH A HEAT INPUT RATING OF 395 MM BTU/HR (LHV) WHEN OPERATED ON NATURAL GAS AND 398 MM BTU/HR (LHV) WHEN OPERATED ON LIQUID FUEL, EQUIPPED WITH A WATER INJECTION SYSTEM AND CORMETECH SELECTIVE CATALYTIC REDUCTION (SCR) SYSTEM INCLUDING AUTOMATIC AMMONIA INJECTION CONTROL SYSTEM FOR CONTROL OF NOX, CONTINUOUS EMISSIONS MONITORING SYSTEM (CEMS), DATA ACQUISITION AND RECORDING SYSTEMS AND AND THE OPTION OF AN OXIDATION CATALYST SYSTEM: UNIT 100 (WEST UNIT) THE COMBINED TOTAL ELECTRICAL NOMINAL POWER OUTPUT FROM THE LARKSPUR POWER PLANT, INCLUDES POWER FROM UNIT 100 AND UNIT 200 IS 90 MW. 976094 EAD 01/06/03 (982160 11/04) 976138 AND 976094 04/20/05 (981537 04/05) 983806 12/29/05 EAD

1 7630

WILDFLOWER ENERGY LP/LARKSPUR 

976138

ONE (1) GENERAL ELECTRIC 45 MW NOMINALLY RATED MODEL LM 6000 PC SPRINT SIMPLE CYCLE GAS TURBINE WITH A HEAT INPUT RATING OF 395 MM BTU/HR (LHV) WHEN OPERATED ON NATURAL GAS AND 398 MM BTU/HR (LHV) WHEN OPERATED ON LIQUID FUEL, EQUIPPED WITH A WATER INJECTION SYSTEM AND CORMETECH SELECTIVE CATALYTIC REDUCTION (SCR) SYSTEM INCLUDING AUTOMATIC AMMONIA INJECTION CONTROL SYSTEM FOR CONTROL OF NOX, CONTINUOUS EMISSIONS MONITORING SYSTEM (CEMS), DATA ACQUISITION AND RECORDING SYSTEMS AND THE OPTION OF AN OXIDATION CATALYST SYSTEM: UNIT 200 (EAST UNIT). THE COMBINED TOTAL ELECTRICAL NOMINAL POWER OUTPUT FROM THE LARKSPUR POWER PLANT, INCLUDING THE POWER FROM UNIT 100 AND UNIT 200 IS 90 MW 976094 AND 976136 EAD 1/6/03 (982160 11/04) 979094 AND 976136 EAD 4/20/05 (981537 04/20/05) 983806 EAD 12/29/05

1 7835 CALPEAK POWER LLC 976502

GAS TURBINE (49.5 MW): PRATT & WHITNEY, MODEL FT-8 (DLN), TWIN-PAC (TWO SIMPLE CYCLE GAS TURBINES WITH COMMON GENERATOR AND EXHAUST), 500 MMBTU/HR TOTAL HEAT INPUT, NATURAL GAS FIRED, WITH EXHAUST AIR COOLING, A PEERLESS MANUFACTURING COMPANY SELECTIVE CATALYTIC REDUCTION (SCR) SYSTEM WITH A HALDOR CATALYST, AN ENGELHARD OXIDATION CATALYST SYSTEM, A CONTINUOUS EMISSION MONITORING SYSTEM (CEMS), AND CONTINUOUS PARAMETRIC MONITORS. (976502AFS11JUL2002)(978638 ALC 09/04)(983962 & 984416 EAD 6/07/07)

1A 86017 CA ST OF DEPT O 860159

ONE(1) SOLAR CENTAUR GSC 4500 COMBUSTION TURBINE MODEL GS1-CB-KA, SERIAL NUMBER CG86N28; ELECTRICL GENRATOR RATED AT 2.93 MW; WASTE HEAT RECOVERY; ONE (1) COEN MODEL GDB-300 DUCT BURNER MODIFIED FOR MAXIMUM HEAT INPUT OF 16 MM BTU/HR WITH A BYPASS VALVE AND SECONDARY EXHAUST, WHICH ALLOWS THE EXHAUST TO BYPASS THE DUCTBURNER/HEAT RECOVERY BOILER. APP.#910523 RLB 5/25/93 (9/24/02 COMPLIANCE REQUESTED EQ. DESC. CHANGE-AFS)

1A OTAY MESA ENE 978379

Power Station #1 consisting of: one Gas Turbine (171.7 MW nominal): General Electric, Model 7FA, with DLN 2.6 low-NOx burners, natural gas fired, 1607.1 MMBtu/hr nominal heat input (LHV), S/N TBD, with a heat recovery steam generator (HRSG) with a 388.1 MMBtu/hr duct burner, NooterEriksen, vented to a selective catalytic reduction (SCR) system, equipped with a continuous emission monitoring system (CEMS); common to both power stations are a steam turbine generator (277 MW nominal), Siemans-Westinghouse, Model KN, S/N TBD; two air-cooled condensers, GEA, 295’L x 123’W x 76’H; a wet surface air cooler, Niagara Blower Co., Model RWC 48240-2F16, or equivalent; and an auxiliary boiler, 87 MMBtu/hr, with low-NOx burners. 

1A OTAY MESA ENE 978380

Power Station #2 consisting of: one Gas Turbine (171.7 MW nominal): General Electric, Model 7FA, with DLN 2.6 low-NOx burners, natural gas fired, 1607.1 MMBtu/hr nominal heat input (LHV), S/N TBD, with a heat recovery steam generator (HRSG) with a 388.1 MMBtu/hr duct burner, NooterEriksen, vented to a selective catalytic reduction (SCR) system, equipped with a continuous emission monitoring system (CEMS); common to both power stations are a steam turbine generator (277 MW nominal), Siemans-Westinghouse, Model KN, S/N TBD; two air-cooled condensers, GEA, 295’L x 123’W x 76’H; a wet surface air cooler, Niagara Blower Co., Model RWC 48240-2F16, or equivalent; and an auxiliary boiler, 87 MMBtu/hr, with low-NOx burners. 

DB = Duct BurnerComb = Combined cycle including combined heat and power (i.e., cogeneration)Simple = simple cycleDF = Diffusion FlameLPM = Lean PremixedAero = AeroderivativeInd = Industrial SCR = Selective Catalytic ReductionWI = Water InjectionOxCat = Oxidation Catalyst

8/11/2011 7:48 PM NG & Diesel Turbine Summary 
M_DBA PO_NUM EQUIP_DESC

WILDFLOWER ENERGY LP/LARKSPUR 

976094

ONE (1) GENERAL ELECTRIC 45 MW NOMINALLY RATED MODEL LM 6000 PC SPRINT SIMPLE CYCLE GAS TURBINE WITH A HEAT INPUT RATING OF 395 MM BTU/HR (LHV) WHEN OPERATED ON NATURAL GAS AND 398 MM BTU/HR (LHV) WHEN OPERATED ON LIQUID FUEL, EQUIPPED WITH A WATER INJECTION SYSTEM AND CORMETECH SELECTIVE CATALYTIC REDUCTION (SCR) SYSTEM INCLUDING AUTOMATIC AMMONIA INJECTION CONTROL SYSTEM FOR CONTROL OF NOX, CONTINUOUS EMISSIONS MONITORING SYSTEM (CEMS), DATA ACQUISITION AND RECORDING SYSTEMS AND AND THE OPTION OF AN OXIDATION CATALYST SYSTEM: UNIT 100 (WEST UNIT) THE COMBINED TOTAL ELECTRICAL NOMINAL POWER OUTPUT FROM THE LARKSPUR POWER PLANT, INCLUDES POWER FROM UNIT 100 AND UNIT 200 IS 90 MW. 976094 EAD 01/06/03 (982160 11/04) 976138 AND 976094 04/20/05 (981537 04/05) 983806 12/29/05 EAD

WILDFLOWER ENERGY LP/LARKSPUR 

976138

ONE (1) GENERAL ELECTRIC 45 MW NOMINALLY RATED MODEL LM 6000 PC SPRINT SIMPLE CYCLE GAS TURBINE WITH A HEAT INPUT RATING OF 395 MM BTU/HR (LHV) WHEN OPERATED ON NATURAL GAS AND 398 MM BTU/HR (LHV) WHEN OPERATED ON LIQUID FUEL, EQUIPPED WITH A WATER INJECTION SYSTEM AND CORMETECH SELECTIVE CATALYTIC REDUCTION (SCR) SYSTEM INCLUDING AUTOMATIC AMMONIA INJECTION CONTROL SYSTEM FOR CONTROL OF NOX, CONTINUOUS EMISSIONS MONITORING SYSTEM (CEMS), DATA ACQUISITION AND RECORDING SYSTEMS AND THE OPTION OF AN OXIDATION CATALYST SYSTEM: UNIT 200 (EAST UNIT). THE COMBINED TOTAL ELECTRICAL NOMINAL POWER OUTPUT FROM THE LARKSPUR POWER PLANT, INCLUDING THE POWER FROM UNIT 100 AND UNIT 200 IS 90 MW 976094 AND 976136 EAD 1/6/03 (982160 11/04) 979094 AND 976136 EAD 4/20/05 (981537 04/20/05) 983806 EAD 12/29/05

CALPEAK POWER LLC 976502

GAS TURBINE (49.5 MW): PRATT & WHITNEY, MODEL FT-8 (DLN), TWIN-PAC (TWO SIMPLE CYCLE GAS TURBINES WITH COMMON GENERATOR AND EXHAUST), 500 MMBTU/HR TOTAL HEAT INPUT, NATURAL GAS FIRED, WITH EXHAUST AIR COOLING, A PEERLESS MANUFACTURING COMPANY SELECTIVE CATALYTIC REDUCTION (SCR) SYSTEM WITH A HALDOR CATALYST, AN ENGELHARD OXIDATION CATALYST SYSTEM, A CONTINUOUS EMISSION MONITORING SYSTEM (CEMS), AND CONTINUOUS PARAMETRIC MONITORS. (976502AFS11JUL2002)(978638 ALC 09/04)(983962 & 984416 EAD 6/07/07)

CA ST OF DEPT O 860159

ONE(1) SOLAR CENTAUR GSC 4500 COMBUSTION TURBINE MODEL GS1-CB-KA, SERIAL NUMBER CG86N28; ELECTRICL GENRATOR RATED AT 2.93 MW; WASTE HEAT RECOVERY; ONE (1) COEN MODEL GDB-300 DUCT BURNER MODIFIED FOR MAXIMUM HEAT INPUT OF 16 MM BTU/HR WITH A BYPASS VALVE AND SECONDARY EXHAUST, WHICH ALLOWS THE EXHAUST TO BYPASS THE DUCTBURNER/HEAT RECOVERY BOILER. APP.#910523 RLB 5/25/93 (9/24/02 COMPLIANCE REQUESTED EQ. DESC. CHANGE-AFS)

OTAY MESA ENE 978379

Power Station #1 consisting of: one Gas Turbine (171.7 MW nominal): General Electric, Model 7FA, with DLN 2.6 low-NOx burners, natural gas fired, 1607.1 MMBtu/hr nominal heat input (LHV), S/N TBD, with a heat recovery steam generator (HRSG) with a 388.1 MMBtu/hr duct burner, NooterEriksen, vented to a selective catalytic reduction (SCR) system, equipped with a continuous emission monitoring system (CEMS); common to both power stations are a steam turbine generator (277 MW nominal), Siemans-Westinghouse, Model KN, S/N TBD; two air-cooled condensers, GEA, 295’L x 123’W x 76’H; a wet surface air cooler, Niagara Blower Co., Model RWC 48240-2F16, or equivalent; and an auxiliary boiler, 87 MMBtu/hr, with low-NOx burners. 

OTAY MESA ENE 978380

Power Station #2 consisting of: one Gas Turbine (171.7 MW nominal): General Electric, Model 7FA, with DLN 2.6 low-NOx burners, natural gas fired, 1607.1 MMBtu/hr nominal heat input (LHV), S/N TBD, with a heat recovery steam generator (HRSG) with a 388.1 MMBtu/hr duct burner, NooterEriksen, vented to a selective catalytic reduction (SCR) system, equipped with a continuous emission monitoring system (CEMS); common to both power stations are a steam turbine generator (277 MW nominal), Siemans-Westinghouse, Model KN, S/N TBD; two air-cooled condensers, GEA, 295’L x 123’W x 76’H; a wet surface air cooler, Niagara Blower Co., Model RWC 48240-2F16, or equivalent; and an auxiliary boiler, 87 MMBtu/hr, with low-NOx burners. 

r

ed cycle including combined heat and power (i.e., cogeneration)

cycle

ame

mixed

ative

Catalytic Reduction

ion

n Catalyst

Mfg Model Type

Turbine 

Rated 

Power 

Output, 

MW

Turbine 

Rated Heat 

Input 

(HHV), 

MMBtu/hr

Combustor Duct Burner

Duct 

Burner 

Rated 

Heat 

Input, 

MMBtu

DB 

Comb

ustor

Rated 

DB 

Heat 

Input 

(HHV), 

MMBTu

/hr Cycle

Add-on 

NOx 

Control

InComb

utor 

NOx 

Contr

ol

CO/VOC 

Control

No. Te

Fired o

Natur

Gas w

DB O

GE LM6000PC SPRINT Aero 45 395 DF — — — — Simple SCR. WI — 0 GE LM6000PC SPRINT Aero 45 395 DF — — — — Simple SCR. WI — 0 

PW FT-8 Aero 49.5 500 LPM — — — — Simple SCR. — OxCat 0 

SOLAR GSI-CB- KA Ind 2.93 DF DB 16 16 Comb — WI — 5 

GE 7FA Ind 171.7 1607.1 LPM DB 388.1 388.1 Comb SCR — — 2 GE 7FA Ind 171.7 1607.1 LPM DB 388.1 388.1 Comb SCR — — 2 

8/11/2011 7:48 PM NG & Diesel Turbine Summary 
M_DBA PO_NUM EQUIP_DESC

WILDFLOWER ENERGY LP/LARKSPUR 

976094

ONE (1) GENERAL ELECTRIC 45 MW NOMINALLY RATED MODEL LM 6000 PC SPRINT SIMPLE CYCLE GAS TURBINE WITH A HEAT INPUT RATING OF 395 MM BTU/HR (LHV) WHEN OPERATED ON NATURAL GAS AND 398 MM BTU/HR (LHV) WHEN OPERATED ON LIQUID FUEL, EQUIPPED WITH A WATER INJECTION SYSTEM AND CORMETECH SELECTIVE CATALYTIC REDUCTION (SCR) SYSTEM INCLUDING AUTOMATIC AMMONIA INJECTION CONTROL SYSTEM FOR CONTROL OF NOX, CONTINUOUS EMISSIONS MONITORING SYSTEM (CEMS), DATA ACQUISITION AND RECORDING SYSTEMS AND AND THE OPTION OF AN OXIDATION CATALYST SYSTEM: UNIT 100 (WEST UNIT) THE COMBINED TOTAL ELECTRICAL NOMINAL POWER OUTPUT FROM THE LARKSPUR POWER PLANT, INCLUDES POWER FROM UNIT 100 AND UNIT 200 IS 90 MW. 976094 EAD 01/06/03 (982160 11/04) 976138 AND 976094 04/20/05 (981537 04/05) 983806 12/29/05 EAD

WILDFLOWER ENERGY LP/LARKSPUR 

976138

ONE (1) GENERAL ELECTRIC 45 MW NOMINALLY RATED MODEL LM 6000 PC SPRINT SIMPLE CYCLE GAS TURBINE WITH A HEAT INPUT RATING OF 395 MM BTU/HR (LHV) WHEN OPERATED ON NATURAL GAS AND 398 MM BTU/HR (LHV) WHEN OPERATED ON LIQUID FUEL, EQUIPPED WITH A WATER INJECTION SYSTEM AND CORMETECH SELECTIVE CATALYTIC REDUCTION (SCR) SYSTEM INCLUDING AUTOMATIC AMMONIA INJECTION CONTROL SYSTEM FOR CONTROL OF NOX, CONTINUOUS EMISSIONS MONITORING SYSTEM (CEMS), DATA ACQUISITION AND RECORDING SYSTEMS AND THE OPTION OF AN OXIDATION CATALYST SYSTEM: UNIT 200 (EAST UNIT). THE COMBINED TOTAL ELECTRICAL NOMINAL POWER OUTPUT FROM THE LARKSPUR POWER PLANT, INCLUDING THE POWER FROM UNIT 100 AND UNIT 200 IS 90 MW 976094 AND 976136 EAD 1/6/03 (982160 11/04) 979094 AND 976136 EAD 4/20/05 (981537 04/20/05) 983806 EAD 12/29/05

CALPEAK POWER LLC 976502

GAS TURBINE (49.5 MW): PRATT & WHITNEY, MODEL FT-8 (DLN), TWIN-PAC (TWO SIMPLE CYCLE GAS TURBINES WITH COMMON GENERATOR AND EXHAUST), 500 MMBTU/HR TOTAL HEAT INPUT, NATURAL GAS FIRED, WITH EXHAUST AIR COOLING, A PEERLESS MANUFACTURING COMPANY SELECTIVE CATALYTIC REDUCTION (SCR) SYSTEM WITH A HALDOR CATALYST, AN ENGELHARD OXIDATION CATALYST SYSTEM, A CONTINUOUS EMISSION MONITORING SYSTEM (CEMS), AND CONTINUOUS PARAMETRIC MONITORS. (976502AFS11JUL2002)(978638 ALC 09/04)(983962 & 984416 EAD 6/07/07)

CA ST OF DEPT O 860159

ONE(1) SOLAR CENTAUR GSC 4500 COMBUSTION TURBINE MODEL GS1-CB-KA, SERIAL NUMBER CG86N28; ELECTRICL GENRATOR RATED AT 2.93 MW; WASTE HEAT RECOVERY; ONE (1) COEN MODEL GDB-300 DUCT BURNER MODIFIED FOR MAXIMUM HEAT INPUT OF 16 MM BTU/HR WITH A BYPASS VALVE AND SECONDARY EXHAUST, WHICH ALLOWS THE EXHAUST TO BYPASS THE DUCTBURNER/HEAT RECOVERY BOILER. APP.#910523 RLB 5/25/93 (9/24/02 COMPLIANCE REQUESTED EQ. DESC. CHANGE-AFS)

OTAY MESA ENE 978379

Power Station #1 consisting of: one Gas Turbine (171.7 MW nominal): General Electric, Model 7FA, with DLN 2.6 low-NOx burners, natural gas fired, 1607.1 MMBtu/hr nominal heat input (LHV), S/N TBD, with a heat recovery steam generator (HRSG) with a 388.1 MMBtu/hr duct burner, NooterEriksen, vented to a selective catalytic reduction (SCR) system, equipped with a continuous emission monitoring system (CEMS); common to both power stations are a steam turbine generator (277 MW nominal), Siemans-Westinghouse, Model KN, S/N TBD; two air-cooled condensers, GEA, 295’L x 123’W x 76’H; a wet surface air cooler, Niagara Blower Co., Model RWC 48240-2F16, or equivalent; and an auxiliary boiler, 87 MMBtu/hr, with low-NOx burners. 

OTAY MESA ENE 978380

Power Station #2 consisting of: one Gas Turbine (171.7 MW nominal): General Electric, Model 7FA, with DLN 2.6 low-NOx burners, natural gas fired, 1607.1 MMBtu/hr nominal heat input (LHV), S/N TBD, with a heat recovery steam generator (HRSG) with a 388.1 MMBtu/hr duct burner, NooterEriksen, vented to a selective catalytic reduction (SCR) system, equipped with a continuous emission monitoring system (CEMS); common to both power stations are a steam turbine generator (277 MW nominal), Siemans-Westinghouse, Model KN, S/N TBD; two air-cooled condensers, GEA, 295’L x 123’W x 76’H; a wet surface air cooler, Niagara Blower Co., Model RWC 48240-2F16, or equivalent; and an auxiliary boiler, 87 MMBtu/hr, with low-NOx burners. 

r

ed cycle including combined heat and power (i.e., cogeneration)

cycle

ame

mixed

ative

Catalytic Reduction

ion

n Catalyst

Natural 

Gas 

DB Off 

NO2/NOx 

Standard 

Deviation

Natural 

Gas 

DB Off 

Average 

Load, %

No. Tests 

Fired on 

Diesel Oil

Oil 

Average 

NOx, ppmv 

@ 15% O2

Oil 

Average 

NO2/Nox

Oil 

Maximum 

NO2/NOx

Oil 

Minimum 

NO2/NOx

Oil 

NO2/NOx 

Standard 

Deviation

Oil 

Average 

Load, % N

4.16 101.41 1 11.10 5.70 5.70 5.70 #DIV/0! 98.229.48 103.11 1 12.10 2.80 2.80 2.80 #DIV/0! 100.005.77 95.96 0 N/A N/A N/A N/A N/A N/A

N/A N/A 0 N/A N/A N/A N/A N/A N/A

0.52 133.37 0 N/A N/A N/A N/A N/A N/A

#DIV/0! 99.59 0 N/A N/A N/A N/A N/A N/A

8/11/2011 7:48 PM NG & Diesel Turbine Summary 
ATTACHMENT D 

February 3, 2011 Email from Ralph DeSiena to Eric Walther 
From: Desiena, Ralph [mailto:Ralph.Desiena@sdcounty.ca.gov] 

Sent: Thursday, February 03, 2011 11:39 AM 

To: Eric Walther 

Cc: Moore, Steve; Reeve, Bill; Desiena, Ralph 

Subject: RE: CEC request for met data on the Pio Pico Energy Center Project 

Eric,

I’m attaching the Aermet data you requested for 2004 and 2005.

Also attached is the revised 2008 data, which now includes the missing end period, a little over

one month, of that data.

In response to your request from CEC is the following:

The recommended approach for processing digitized land cover data to determine the effective

Bowen ratio and Albedo for input to AERMET is to average the surface characteristics across a

representative domain without any direction or distance dependency. The recommended

default domain is a 10km by 10km region centered on the measurement site.  A domain

representative of the application site may be more appropriate for some applications,

particularly

if the majority of sources are elevated releases.   

For this project we chose to use the proposed Pio Pico facility location as the center of the

domain used in determination of the Bowen Ratios and Albedos on a monthly basis since the

proposed facility is comprised of elevated sources.   AERSURFACE was used  for this purpose.  

We modify the seasonal categories for San Diego County  for input to the AERSURFACE program

as follows:

                Transitional Spring:  March and April

                Midsummer: May, June, July, August, September

                Autumn with unharvested cropland: October, November, December, January, February

Since AERSUFACE currently uses a Land Use data base from 1992, and does not take buildings in

to account, we then modified the Surface Roughness value determined for the actual

Meteorological tower location (SDAPCD Otay monitoring station), which is located

approximately 1.8 miles SW of the proposed facility site.  The value obtained using AERSURFACE

was approximately 0.2.   We replaced this with a Surface Roughness value of 0.7 based on a

review of aerial photos for the area.  We feel that this better represents the vicinity of the

Meteorological tower as a light industrial and residential area that includes northern Mexico and

the U.S border area.

If you have any questions please let me know.

Regards,

Ralph

Ralph DeSiena

Air Pollution Meteorologist

San Diego County Air Pollution Control 
10124 Old Grove Rd. 

San Diego, CA 92131 

858-586-2772 fax 858-586-2759

www.sdapcd.org