March 4, 2015

IMPERIAL COUNTY AIR POLLUTION CONTROL DISTRICT

Authority to Construct and Permit to Operate Review

Permit: #2000H-9

Source Name: CalEnergy Operating Corporation

Source Type: Geothermal

Applied For: Unit 3 Cooling Tower Modification 

Mailing Address: 7030 Gentry Road

Calipatria, CA 92233

Project Location: CalEnergy Region 1

6229 Crummer Road

Calipatria, CA 92233

Responsible Person: Graeme Donaldson,

President

Office: (760) 348-4200

Person in Charge at Location: Janet E. Hagen,

Operations Site Manager

Office: (760) 348-4247

Permit Reviewer: Thomas Brinkerhoff,

APC Engineer

Introduction

Graeme Donaldson, President of the CalEnergy Operating Corporation (CalEnergy),

has submitted a permit application to the Air District for the modification of existing Air 

District Permit No. 2000H-8. This permit regulates the air emission units of the Region 

1 Geothermal Power Plant Facility (Region 1), which is located at 6229 Crummer Rd. in 

Calipatria, CA. CalEnergy is proposing to replace the current drift eliminators of the 

cooling tower at Unit 3 with new eliminators that have a higher drift efficiency, which in 

turn will reduce PM10 air emissions at the stationary source. The estimated reduction 

in emissions will satisfy the PM10 offset requirement for Permit 2000H-8, which was 

established in 2013 as CalEnergy increased the potential to emit (PTE) for the non1
condensable gases (NCGs) treated by the Regenerative Thermal Oxidizer (RTO) 

abatement system and KinPactor venturi scrubber. 

This review will result in a new Authority to Construct (ATC) being issued to CalEnergy, 

once the permit review and application has been made available to the public for the 

required 30-day review period per Air District Rule 206. CalEnergy plans to carry out 

this project in the second half of February 2015, during the annual maintenance outage 

of Region 1. Once the upgrade is finished, the Air District will inspect the site and verify 

compliance before issuing a Permit to Operate (PTO) to CalEnergy for the modification. 

The Region 1 facility, located in the Salton Sea Known Geothermal Resource Area, 

consists of five different site locations that are classified as stationary sources, which 

are referred to as Unit 1 through Unit 5. These five different units are grouped into three 

areas – Units 1 and 2, Units 3 and 4, and Unit 5, having a net output rating of 27, 94 

and 51 megawatts (MW) respectively. The electrical production capacity for the entire 

Region 1 geothermal facility is 175.0 MW. Up to 16,000,000 pounds per hour of 

geothermal brine is processed in a centralized area at Region 1 which is located at 

Units 3 and 4 and Unit 5. 

Facility Description

Electrical power generation at Region 1 of CalEnergy is carried out by bringing hot brine 

to the surface via production wells for extraction of heat and further reinjection of the 

residual brine. High and standard pressure steam from the brine is sent from Region 1 

to steam turbines for the units. The steam is then routed to a condenser where the noncondensable gases (NCGs) are removed by vacuum pumps and redirected to the RTO 

systems at Units 1 and 2 and 3 and 4 which abate the hydrogen sulfide (H2S) 

emissions. The RTO systems also abate benzene and methane emission from the 

NCG stream by combusting gasses in the RTO units. Propane fuel is used in the RTO 

systems to drive the combustion process. Sulfur Dioxide (SO2) that is formed due to 

the combustion of H2S in the RTOs is controlled by caustic scrubber systems 

downstream of each RTO. Once the gases leave the scrubbers at Units 1 and 2 and 

Units and 4, they are moved to the American Air Filter (AAF) KinPactor venturi scrubber 

systems that also each have an air cyclone separator, which remove PM10 from the 

streams. Finally the NCGs are vented to the atmosphere through a stack which serves 

Units 1 and 2 and a stack which serves Units 3 and 4. 

Unit 5 of Region 1 accepts lower pressure steam from the brine system at Region 1, 

which is in turn routed to a turbine for electricity generation. The exhausted steam from 

each turbine is directed down into dedicated condensers that are cooled by 

conventional closed loop recirculating water systems utilizing a mechanical draft cooling 

tower. For Units 1, 2, 3, and 4, condensable gasses from each turbine are sent to the 

oxidizer boxes in the cooling towers for each unit where H2S is abated. Region 1 also

operates other related processing equipment: mechanical and electrical equipment, an 

acid handling system, cooling water pumps, condensate pumps, reactors, clarifiers, a 

2
lime handling system, a filter cake handling system, and brine pumps. Emergency 

equipment also is installed and operates at the stationary sources of Region 1, 

consisting of various fire pumps and diesel-powered standby generators. 

Project Description

CalEnergy is proposing to replace the existing Unit 3 cooling tower drift eliminators, 

which have a drift loss of 0.001%, with CF80Max Counterflow Cellular Drift Eliminators. 

The new drift eliminators have a certified drift loss rate of 0.0005% per CTI Standard 

140, the industry standard for testing of cooling tower drift. This type of drift eliminators 

are specifically designed for applications requiring very low drift levels in counterflow 

cooling towers. The drift eliminators have a beveled drainage tip design that reduces 

pressure drop by up to 25%. The estimated reduction of PM10 emissions from the 

project will reduce the Potential to Emit (PTE) for Region 1 in the amount of 3.54 tons, 

and therefore will result in CalEnergy satisfying the current PM10 offset requirements 

for Region 1 which amount 2.92 tons of Stationary PM10 Emission Reduction Credits 

(ERCs). 

Air Emissions

Cooling Towers PM10 Emissions

In the first subsection below, the Air District has calculated the total Potential to Emit 

(PTE) for Region 1. Particulate Matter (PM10) emissions from the cooling towers at 

Region 1 are estimated using the methodology found in U.S. EPA AP-42, Sec. 13.4. 

The first section begins with the review of the modified emissions to the cooling tower at 

Unit 3, showing the emission reduction due to the installation of the new drift 

eliminators. The historical actual emissions (HAE) from Unit 3’s cooling tower is based 

on the data available from the last two years (8 quarters), which meets the HAE 

definition per Air District Rule 101. The HAE consists of the PM10 emissions data that 

was reported to the Air District in order to satisfy permit reporting requirements. In 

calculating the new PTE for the upgraded Unit 3 cooling tower, the average TDS from 

2013-2014 was used, which is 6,615 ppm. 

Table 1: Parameters for Unit 3 Cooling Tower PTE

Parameter Value Units

Unit 3 Water Recirc. Rate 82,100 gal/min

Unit 3 Drift Loss -

Existing 0.001 %

Water Density 8.34 lb/gal

Unit 3 Drift Loss - New 0.0005 %

3
Table 2: Historic Actual Emissions, New Potential to Emit, and PM10 Emissions Decrease

Region 1, Unit 3 Cooling Tower

PM 10 Emissions (lb/day) PM 10 Emissions (tons/Quarter)

Quarter 2012 2013 2014 Average

New 

System 

PTE HAE New System

Emission 

Reductions

Quarter 1 -- 41.17 38.48 39.83 32.61 1.79 1.47 0.32

Quarter 2 -- 62.26 46.71 54.49 32.61 2.48 1.47 1.01

Quarter 3 -- 93.20 51.50 72.35 32.61 3.33 1.47 1.86

Quarter 4 30.72 47.95 -- 39.34 32.61 1.81 1.47 0.34

Tons/yr 9.41 5.87 3.54

The PTE for the cooling towers at Units 1, 2, 4, and 5 are based on the drift rate of each 

cooling tower, operational data from October 31, 2005 to May 21, 2012, and the permit 

application addendum submitted by CalEnergy in February 2013 for the permit’s 

previous modification. 

 Table 3: New Region 1 Cooling Tower PTE

Cooling 

Tower

Water Circulation 

Rate (gpm)

Estimated TDS*

(ppm)

Drift ( % ) PM 10 

(lbs/day)

Unit 1 19,360 7,783 0.001 18.10

Unit 2 36,280 7,525 0.0015 49.18

Unit 3 82,100 6,615 0.0005 32.61

Unit 4 90,000 7,130 0.0015 115.60

Unit 5 101,000 4,146 0.001 50.29

Total PM10 Emissions (lbs/day): 265.78

Compliance Margin PTE (lbs/day): 270.06

Compliance Margin PTE (tons/yr): 49.29

* The actual TDS concentration in the recirculating water for each cooling tower varies and may at times 

be higher than the Estimated TDS levels listed in the above table. For the purposes of establishing a 

PTE however, CalEnergy calculated the 95% confidence of the maximum TDS for each cooling tower and 

used this as the Estimated TDS for each Unit. Neither the TDS values in the table, nor the nominal 

recirculation rate constitute permit limits on the cooling towers. Instead the permit limit is established by 

the Compliance Margin PTE for PM10 emissions from all the cooling towers combined. 

Taking the daily PM10 emissions of 270.06 pounds, the annual PM10 emissions from 

the cooling towers would be 49.29 tons. Due to the fact that the water circulation rates 

and total dissolved solids in the cooling tower may fluctuate, and that CalEnergy is 

voluntarily reducing PM10 emissions of the Unit 3 cooling tower through the installation 

of the new drift eliminators, the permittee will still have a compliance margin built into 

the emission limit for its cooling towers. 

4
RTO & Ox-Box Normal Operations PTE

The below emissions calculations show the potential to emit for the RTO units, as well 

as the emissions from the Oxidizer Box units at Region 1. Table 1 displays the daily 

and annual emissions from Units 1&2, whereas Table 2 displays the daily and annual 

emissions from Units 3&4. The benzene and H2S emissions from the cooling tower 

outlet of Unit 5 are now included in this section in Table 3, since the emissions from Unit 

5 are not treated by an RTO system as one is not present at that site: 

 Table 1: Units 1&2 PTE

Pollutants

RTO Stack 

(lbs/day)

Outlet Ox-Box 

(lbs/day)

Total 

Emissions 

(lbs/day)

Annual 

Emissions 

(tons/yr)

Benzene 2.9 2.9 0.518

H2S 50.4 151.2 201.6 36.288

Ammonia 0.96 2,966.0 2,967.0 541.470

Methane 83.3 83.3 15.202

SOx 85.2 85.2 15.549

NOx 60.0 60.0 10.95

PM10 20.0 20.0 3.65

Table 2: Units 3&4 PTE

Pollutants

RTO Stack

(lbs/day)

Outlet OxBox (lbs/day)

Total 

Emissions 

(lbs/day)

Annual 

Emissions 

(tons/yr)

Benzene 4.56 4.56 0.814

H2S 102.8 194.8 297.6 53.51

Ammonia 0.91 6,096.0 6,096.9 1112.686

Methane 123.1 123.1 22.466

SOx 86.4 86.4 15.768

NOx 75.0 75.0 13.688

PM10 40.0 40.0 7.30

Table 3: Unit 5 PTE 

Pollutants

Cooling Tower 

Outlet (lbs/day)

Total Emissions 

(lbs/day)

Annual Emissions 

(tons/yr)

Benzene 0.24 0.24 0.04

H2S 48.0 48.0 8.76

Emergency Diesel ICE Emissions 

5
Region 1 has a total of four stationary emergency units, all driven by Tier 0 diesel 

engines. The emission factors used in the below calculations come from EPA’s AP-42 

Manual, Section 3.3. The units consist of three emergency generator sets and one fire 

pump which are all greater than 50 horsepower and limited to 20 hours per year for 

maintenance and testing (M&T) purposes. CalEnergy is not allowed to test the Unit 5 

generator set on the same day as the other emergency units, in an effort to limit the 

daily PTE. Hence, only the M&T emissions from the Unit 5 generator set are included in 

the new daily PTE for Region 1, since it is the largest amount of emissions possible per 

day from these units. Each unit’s annual PTE is based on 500 hours of operation, 

which include the allowed M&T hours, per Title V applicability requirements:

Table 4: Daily Emergency ICE Emissions 

Potential to emit (lbs/day)

Equipment Horsepower Hours/Day NOx CO SOx PM10 VOC

Units 1&2 Gen Set 570 1.0 17.67 3.81 1.17 1.26 1.41

Units 3&4 Gen Set 570 1.0 17.67 3.81 1.17 1.26 1.41

Caterpillar Fire 

Pump 300 1.0 9.30 2.00 0.62 0.66 0.74

Unit 5 Gen Set 1609 1.0 49.88 10.75 3.30 3.55 3.97

Total: 94.52 20.37 6.25 6.72 7.53

Table 5: Annual Emergency ICE Emissions 

Potential to emit (tons/year)

Equipment NOx CO SOx PM10 VOC

Units 1&2 Gen Set 4.42 0.95 0.29 0.31 0.35

Units 3&4 Gen Set 4.42 0.95 0.29 0.31 0.35

Caterpillar Fire Pump 2.33 0.50 0.15 0.17 0.19

Unit 5 Gen Set 12.47 2.69 0.82 0.89 0.99

Total: 23.63 5.09 1.56 1.68 1.88

Maintenance Outages Emissions

The below set of emissions calculations reflect the amount of time the Air District has 

granted CalEnergy for RTO and Oxidizer Box maintenance, which also includes start-up 

and shutdown time for the RTO systems. The calculations are based on 4 days, 24 

hours per day for 96 hours per year for Oxidizer Box maintenance, and 8 days, 24 hours 

per day for 192 hours per year for RTO maintenance:

 

Table 6: Maintenance Outages Emissions 

PTE (lbs/hr) PTE (lbs/day) PTE (lbs/yr)

Equipment H2S Benzene H2S Benzene H2S Benzene

Unit 1 Oxidizer Box 23.8 571.2 2284.8

6
Unit 2 Oxidizer Box 12.3 295.2 1180.8

Unit 3 Oxidizer Box 14.1 338.4 1353.6

Unit 4 Oxidizer Box 12.1 290.4 1161.6

Subtotal: 62.3 1495.2 5980.8

Units 1&2 RTO 36.9 2.0 885.6 48.0 7084.8 384

Units 3&4 RTO 53.7 2.54 1288.8 60.96 10310.4 487.68

Subtotal: 90.6 4.54 2174.4 108.96 17395.2 871.68

Totals: 152.9 4.54 3669.6 108.96 23376.0 871.68

Oxidizer Box Startup Emissions

The permittee requested in the last permit modification that language be inserted into 

Permit 2000H-5 which explicitly states that one startup be allowed for each oxidizer box 

per year. The startup would last no more than two weeks for each unit as the bacteria 

cultures are prepared and the control efficiency is optimized. 

Table 7: Oxidizer Box Units Startup Emissions

PTE (lbs/hr) PTE (lbs/day) PTE (lbs/yr) PTE (tons/yr)

Equipment H2S H2S H2S H2S

Unit 1 Oxidizer Box 23.8 571.2 7996.8 4.00

Unit 2 Oxidizer Box 12.3 295.2 4132.8 2.07

Unit 3 Oxidizer Box 14.1 338.4 4737.6 2.37

Unit 4 Oxidizer Box 12.1 290.4 4065.6 2.03

Subtotal: 62.3 1495.2 20932.8 10.47

Region 1 Total PTE

The final table below summarizes the total daily and annual emissions for Region 1, 

which takes into account the modification of the Unit 3 cooling tower and the resulting 

reduction of PM10 emissions. The daily normal operating PTE includes the 

maintenance and testing emissions from the Unit 5 generator set, whereas the annual 

normal operating PTE includes the maintenance and testing emissions from all four of 

the emergency combustion units at Region 1. CalEnergy has committed that that it will 

continue to remain below the Major Source emission threshold of 100 tons per year for 

H2S through efficient operative practices, thereby limiting Region 1 annual H2S 

emissions to 99.0 tons per year: 

Table 8: New Region 1 PTE 

Pollutants

Normal 

Operating 

PTE (lbs/day)

Normal 

Operating 

PTE (tons/yr)

Maintenance 

PTE (tons/yr)

Ox-Box 

Startup PTE 

(tons/yr)

Total Annual 

PTE (tons/yr)

7
Pollutants

Normal 

Operating 

PTE (lbs/day)

Normal 

Operating 

PTE (tons/yr)

Maintenance 

PTE (tons/yr)

Ox-Box 

Startup PTE 

(tons/yr)

Total Annual 

PTE (tons/yr)

Benzene 7.70 1.375 0.436 1.81

H2S 547.2 98.559 11.688 10.47 120.72

Ammonia 9063.87 1654.156 1654.16

Methane 206.4 37.668 37.67

SOx 174.90 32.880 32.88

NOx 184.88 48.267 48.27

PM10 333.61 61.916 61.92

Applicable Rules and Regulations

The following section summarizes the Air District Rules and Regulations which are 

applicable to CalEnergy and the emissions units which are located within the Region 1 

Geothermal Power Plant Facility.

Rule 201 Permits Required

Except as exempted within the Air District Rules and Regulations, new or modified 

sources which may emit or control air contaminants must obtain written authorization 

from the ICAPCD prior to construction. The Region 1 Facility has a wide array of 

emissions sources that require both an Authority to Construct and Permit to Operate 

from the Air District.

Rule 206 Processing of Applications

This Rule contains the guidelines established by the APCD for the processing of 

applications and issuance of permits. This proposed project is classified as a 

Discretionary Permit/non-ministerial project, and will be processed according to the 

procedures herein. Due to the fact that the source’s daily PTE is greater than 100 

pounds per day for the pollutants SO2, PM10, NOx, and H2S, the project will be 

required to follow the public noticing and review requirements of Rule 206.

Rule 207 New and Modified Stationary Source Review

Rule 207 provides preconstruction review requirements for new and modified stationary 

sources to ensure that the operation of such sources do not interfere with the attainment 

or maintenance of ambient air quality standards. 

Rule 207.C.1.a requires Best Available Control Technology (BACT) for equipment with 

the potential to emit 25 pounds per day or more of any nonattainment pollutant or their 

precursors. The proposed cooling tower upgrade at Unit 3 will result in an overall 

decrease of PM10 emissions for the stationary source, with all other pollutants being 

8
unaffected by the proposed project. The new drift eliminators at Unit 3, with a drift loss 

rate of 0.0005%, meet the BACT standard for the modification. Region 1 has also 

fulfilled BACT requirements in the past with the installation and operation of the two 

RTO systems, as well as the KinPactor venturi scrubbers and air cyclone separators. 

Rule 207.C.2.a requires that any new or modified emission source with a potential to 

emit (PTE) greater than 137 pounds per day for ROCs, PM10, NOx or SOx emissions be 

offset by the permittee. The proposed equipment modification will result in a decrease 

of 3.54 tons in PM10 emissions, and will therefore result in CalEnergy fulfilling the 

previous permit condition which required the permittee to offset 2.92 tons of PM10 at 

Region 1. CalEnergy will not be required to offset any other pollutants since the Unit 3 

cooling tower project will not affect the PTE of the facility other than PM10 emissions. 

Rule 208 Permit to Operate

The ICAPCD may inspect and evaluate the new equipment prior to allowing the project 

to operate under its Permit to Operate. The permittee is expected to fully comply so 

that a PTO may be issued upon confirmation of compliance once the proposed 

modification is carried out in full. 

Rule 400.3 Internal Combustion Engines

This rule applies to any internal combustion engine (ICE) with a brake horsepower (bhp) 

rating greater than 50. In order to comply with this Rule, CalEnergy will maintain an 

engine operating log on-site for each of its emergency combustion units (fire pumps, 

emergency generators). Per Air District Policy 40, the NOx emission limit which will be 

required of CalEnergy to comply with for the Detroit 425 kW emergency generators will 

be 20.0 pounds per hour, based on the test result from the October 2014 source test 

and the twenty (20) percent additional factor which is prescribed. The same

methodology will be applied for compliance with CO emission limits, as the CO emission 

limit for the Detroit 425 kW emergency generators will be set at 4.0 pounds per hour 

and 14 pounds per hour for the Detroit 1200 kW emergency generator.

Rule 401 Opacity of Emissions

The opacity of the emissions for the emission units at Region 1, other than uncombined 

water vapor, may not be as dark or darker as designated as No. 1 on the Ringlemann 

Chart (20% opacity) for a period or periods aggregating more than three minutes in any 

one hour. The Permittee will continue to comply with this Rule by utilizing best 

operating and maintenance practices.

Rule 403 General Limitations on the Discharge of Air Contaminants

The limitation in Rule 403 establishes maximum emission rates for particulate matter 

that vary according to the weight of the materials processed. Rule 403 prohibits 

9
emission of particulate matter in excess of the emission rates in Tables 403-1 and 403-

2. CalEnergy will continue to comply with these limitations, as they have consistently 

demonstrated in the past. 

Rule 407 Nuisances

This rule prohibits the discharge from any source air contaminants which cause injury, 

detriment, nuisance, or annoyance to any considerable number of persons or to the 

public, which endanger the comfort, repose, health or safety of any such persons or the 

public, or which cause or have a natural tendency to cause injury or damage to 

business or property. The permittee will be required to comply with this rule at all times

for its permitted Region 1 facility. 

Regulation VIII Fugitive Dust (PM10) Rules 

The Air District Rules under Regulation VIII include requirements and Best Available 

Control Measures (BACM) which operators must implement in order to reduce fugitive 

dust emissions from construction and earthmoving activities, open areas, movement of 

bulk materials, carry out and track out activities, and paved and unpaved roads. 

CalEnergy will continue to be required to comply with Regulation VIII Rules. 

CA Health & Safety Code 42301.6 

California Health and Safety Code, Sec. 42301.6 requires that the Air District prepare a 

public notice for any new or modified source which emits hazardous air emissions that 

is located within 1,000 feet from the outer boundary of a schoolsite, prior to approving a 

Permit to Construct or Modification. The existing stationary source (Region 1), located 

at 6229 Crummer Road, Calipatria, CA, will still emit hazardous air emissions once the 

proposed cooling tower modification is completed. Region 1 is located over 6.0 miles 

away from the nearest school sites, which are the high school, middle school, and 

elementary school of the Calipatria Unified School District, which are all located side by 

side at 601 W. Main St, Calipatria, CA. Therefore, based on this analysis, CalEnergy 

will not be required to notice its project to the public since the source is located more 

than 1,000 feet from the nearest schoolsite. The Air District consulted the online 

Google Tool, Google Maps, as well as the software program Google Earth in making 

this determination.

AB 2588 Assessment

Due to the fact that the proposed diesel generator will emit various air emissions that 

are classified as toxic air contaminants, the emissions unit will be evaluated per the 

requirements of the Air Toxics "Hot Spots" Program (AB 2588). The nearest receptor 

from the source of emissions is a residence located approximately 2.27 miles away from 

the southeast corner of the Region 1 facility. Based on the specifications and permitted 

M&T hours of the four emergency combustion units which are each driven by a diesel 

engine, the Air District analyzed the health risk of these emission units by utilizing the 

10
Hot Spots Scores Prioritization Table Version 2.0, developed by the San Joaquin Valley 

Air Pollution Control District (SJVAPCD). The resulting risk score calculated by the 

prioritization spreadsheet is less than 1.0. Since the risk score is below 10.0, no further 

detailed risk analysis will be required of the applicant. 

Authority to Construct and Permit to Operate Conditions

A. General Conditions

1. This Permit to Operate with Conditions is applicable to the Region 1 facilities 

(Units 1, 2, 3, 4 and 5) and supersedes all other past permit emissions 

limitations. 

2. The facilities shall be constructed and operated in substantial compliance with 

the project description, and operating parameters of the Application 

(FR#2011636404) dated November 3, 2014, and with earlier applications dated: 

July 11, 2011, May 17, 2011; December 23, 2010; August 14, 2008; February 20, 

2008; April 25, 2007; September 24, 1999; December 29, 1997; October 4, 1994; 

March 22, 1987 except as may be modified by more stringent requirements of 

law or these conditions. 

3. Operation of all equipment shall be in compliance with all data and specifications 

submitted with the application under which this permit is issued unless otherwise 

noted below.

4. Operation of all equipment shall be in compliance with applicable APCD Rules 

and Regulations.

5. This permit does not authorize the emissions of air contaminants in excess of 

those allowed by the USEPA (title 40 of the Code of Federal Regulation), the 

State of California Division 26, Part 4, Chapter 3 of the Health and Safety Code, 

or the APCD (Rules and Regulations).

6. This permit cannot be considered permission to violate applicable existing laws, 

regulations, rules or statues of other governmental agencies.

7. The emissions of any regulated pollutant, as defined pursuant to 40 CFR 70.2, 

shall be less than the major source threshold values of Rule 900 B.20, of the 

Imperial County APCD Rules and Regulations.

8. The emissions of any single hazardous air pollutant, as defined pursuant to 

Section 112(b) of the 1990 Clean Air Act and Rule 900 B.20, shall be less than 

10 tons per year. Total combined emissions of all hazardous air pollutants, as 

defined pursuant to Section 112(b) of the 1990 Clean Air Act and Rule 900 B.20, 

shall be less than 25 tons per year.

11
9. No air contaminant shall be released into the atmosphere which causes a public 

nuisance. 

10. All equipment shall be maintained in good operating conditions and shall be 

operated in a manner to minimize emissions of air contaminants into the 

atmosphere.

11. Disturbances of soil related to any construction, demolition, excavation, or other 

earthmoving activities shall comply with the requirements for fugitive dust control.

12. Any unpaved and paved road, and open areas subject to be disturbed by 

vehicles traffic shall comply with the requirements for fugitive dust control.

13. The Permittee shall prevent or cleanup any carry-out or track-out.

14. No air contaminant shall be discharged into the atmosphere for a period or 

periods aggregating more than three minutes in any one hour which is as dark 

as, or darker than, Ringelmann Chart 1 or 20% opacity.

B. Emission Limits

1. CalEnergy Region 1 Units 1 and 2 shall not exceed the following emission limits:

 Table 1. Units 1 and 2 Emission Limits

Pollutant Emission Limits 

(lb/hr)

Emission Limits 

(lb/day)

SO2 3.55 85.2

NOx 2.5 60.0

PM10 from RTO System 0.83 20.0

2. CalEnergy Region 1 Units 3 and 4 shall not exceed the following emission limits:

 Table 2. Units 3 and 4 Emission Limits

Pollutant Emission Limits 

(lb/hr)

Emission Limits 

(lb/day)

SO2 3.6 86.4

NOx 3.13 75.0

PM10 from RTO System 1.67 40.0

3. Facility-wide emissions of PM10 for Region 1 shall be limited to 61.9 tons per 

year, based on the total emissions in any calendar year. 

12
C. Units 1 and 2, and Units 3 and 4 RTO/Scrubber Units

1. Units 1 and 2, and Units 3 and 4 shall not be operated without abatement system 

(RTO and scrubber system) except during times of system maintenance outages, 

which are not to exceed 192 hours annually per abatement system. Use of the 

controls will establish an affirmative defense to any excess emissions during 

startup, shutdown and malfunction if the control equipment is maintained and 

operated in a manner consistent with good practice for minimizing emissions. If 

insufficient NCG are produced to sustain the required temperatures in the RTO, 

Permittee shall supplement the fuel with propane to maintain the required 

operating temperatures.

2. The permittee shall prevent excessive fouling of each RTO and scrubber system 

through a maintenance program which shall not exceed 192 hours per year per 

RTO and scrubber system. 

3. Units 1 and 2 shall not exceed the following emission limits from the controlled 

NCG RTO/Scrubber system and KinPactor venturi scrubber system stack:

a. Benzene emissions 2.9 pounds per day.

b. Hydrogen sulfide emissions 50.4 pounds per day. 

c. Sulfur dioxide emissions 85.2 pounds per day.

d. Nitrogen oxide emissions 60.0 pounds per day. 

e. PM10 emissions 20.0 pounds per day.

4. Units 3 and 4 shall not exceed the following emission limits from the controlled 

NCG RTO/Scrubber system and KinPactor venturi scrubber system stack:

a. Benzene emissions 4.56 pounds per day.

b. Hydrogen sulfide emissions 102.8 pounds per day. 

c. Sulfur dioxide emissions 86.4 pounds per day.

d. Nitrogen oxide emissions 75.0 pounds per day. 

e. PM10 emissions 40.0 pounds per day.

5. The RTOs Units Combustion Chamber shall be operated at a temperature of 

greater than or equal to 1500 degrees Fahrenheit to ensure complete 

combustion. Propane shall be used to maintain the chamber temperature above 

the temperature limit. Compliance with the RTO combustion chamber 

temperature limit shall be based on a 1-hour average that demonstrates that the 

temperature is greater than or equal to 1500°F. 

6. The operating temperature of the RTOs Combustion Chamber shall be monitored 

continuously, with the data being electronically logged every 5 minutes, and shall 

be made available to APCD inspectors upon request.

7. An electronic log shall be maintained on the premises showing hours of 

13
operation, combustion chamber operation temperature and log to document 

routine repairs of the RTO and Scrubber system. These logs shall be available 

for inspection by the APCD inspectors.

8. The operating scrubber water re-circulation rate and scrubber water pH shall be 

continuously monitored, except for periodic calibration for pH in which case data 

will be unavailable. The data shall be electronically logged every five (5) minutes, 

and shall be available to the APCD inspectors to prove compliance.

9. Each KinPactor venturi scrubber system shall be operated at all times while its 

respective RTO and scrubber system is operating at Units 1 and 2, and Units 3 

and 4.

10. Each KinPactor venturi scrubber system shall be maintained to operate in good 

working condition and up to the performance standards of the manufacturer’s 

specifications.

D. Benzene Emissions 

1. This Permit supersedes all permit requirements, limitations and agreements set 

forth in those permits. 

2. Region 1 shall not exceed the following Benzene emission limits during normal 

operations:

Table 4. Region 1 Benzene Emissions Limits

Plant Benzene Mitigation 

Agreement

Emission 

Limits 

(lbs/hr)

Emission 

Limits 

(lbs/day)

Units 1

and 2

Equal to or greater than

90% control or a control

level achievable 

0.12 2.9

Units 3 

and 4

Equal to or greater than

90% control or a control

level achievable

0.19 4.56

Unit 5 No controls necessary, 

average emission rate 0.01 

lbs/hr

<0.01 <0.24

3. The Permittee shall not exceed the Benzene limit of 4.54 lbs/hr at any time 

during a maintenance activity at Region 1. 

14
E. Hydrogen Sulfide Emissions

1. The Permittee shall not exceed the following Hydrogen Sulfide (H2S) emission 

limits during normal operations:

Table 5. Overall Hydrogen Sulfide Emission Limits

Region 1 Plants H2S(lbs/hr) H2S.(lbs/day)

Units 1 and 2 8.4 201.6

Units 3 and 4 12.4 297.6

Unit 5 2.0 48.0

2. The Permittee shall not exceed the H2S limit of 80 lbs/hr at any time during a 

maintenance activity at Region 1. 

3. The Permittee shall not exceed the following annual H2S emission limits: 

Table 6. Region 1 Annual Hydrogen Sulfide Emission Limits

Region 1 Plants H2S (tons/yr)

Units 1 and 2 36.3 

Units 3 and 4 54.0

Unit 5 8.7

4. Region 1 total H2S emissions, including emissions from startup and maintenance 

periods, shall not exceed 99.0 tons per year for the entire Facility on a 12-month 

rolling basis. 

F. Oxidizer Box Units 

1. The Oxidizer Boxes shall follow the below operating conditions:

a. The Permittee shall engage control equipment (oxidizer boxes) upon plant 

startup and shall utilize controls as long as practicable during periods of 

malfunction. Use of the controls will establish an affirmative defense to 

any excess emissions during startup, shutdown and malfunction if the 

control equipment is maintained and operated in a manner consistent with 

good practice for minimizing emissions.

b. The Permittee shall operate the oxidizer boxes for hydrogen sulfide control 

in the condensate to achieve compliance with the hydrogen sulfide 

emission limits.

c. The Permittee shall have a preventative maintenance program for the 

oxidizer boxes.

15
2. Region 1 shall be limited to one (1) startup of each oxidizer box unit, which shall 

last for no more than two weeks (336 hours), adhering to the following protocol: 

a. Startup of the oxidizer boxes shall be aided by inoculating the bacteria 

cultures to enable abatement in a one week period and optimize control 

efficiency the following week.

3. The permittee shall have a preventative maintenance program for each oxidizer 

box which shall not exceed 96 hours per year per oxidizer box.

G. Visible Emissions and Standards

1. Visible emissions shall not exceed 20% opacity for more than 3 minutes in any 1 

hour excluding water vapor.

2. The dry lime handling system shall be equipped with a dust collector to mitigate 

particulate matter and PM10 emissions. The dry lime handling system includes 

the following equipment: 

a. ZMI Porter M-40 Lime Slaking unit rated at 9000 lbs/hr (4.5 tons/hr).

b. 2200 cubic foot dry lime silo

c. Grit shaker and discharge conveyor assembly

d. DF-48 Dust Collector, 1176 cfm capacity, 295 square foot total bag area. 

3. The Permittee shall maintain and operate the dust collector and lime handling 

system in good working order at all times for controlling particulate matter and 

PM 10. The dust collector shall be in operation when the slaker and dry lime 

handling system is in operation. 

4. The Permittee shall not release air contaminants into the atmosphere from the 

dust collector’s exhaust in excess of 0.2 grains per cubic foot of gas at standard 

conditions. 

5. The lime slaker unit must be sealed/contained at all times except when adding 

lime and when in operation.

6. The Permittee shall inspect the dust collector filters every 200 hours of operation 

and maintain in good working order at all times. A log shall be maintained on the 

premises showing hours of operation, routine repairs and inspection dates. This 

log shall be made available for inspection by the ICAPCD.

7. Dust collected by the control equipment shall be maintained in closed containers.

8. All fugitive dust from the lime slaker operation shall be maintained at levels that 

will not exceed 20 percent opacity.

16
H. Cooling Towers PM10 Emissions Limits

1. The Cooling Towers shall not exceed the following emission limit:

 Table 7. Cooling Towers PM10 Emission Limits

All Cooling Towers PM10 (lbs/day)

Region 1 Total PM10 Emission Limit 

in one single day (lbs/day) 270.06

2. The Permittee shall control PM10 by installing Drift Eliminators that comply with 

the drift loss specs claim by the Permittee for the current cooling towers.

3. Permittee shall maintain the cooling towers’ Drift Eliminators (demisters) in good 

working order at all times to perform in accordance with the manufacturer 

specifications in regard to drift loss.

I. Hydrochloric Acid Trans-loading 

1. Total gas concentration from the scrubber stack effluent gas shall not contain 

more than seventy-five (75) parts per million (ceiling) of hydrochloric acid fumes 

and 0.018 lbs/day.

2. The HCL scrubber shall be operated at 99.99% minimum control efficiency.

3. All trans-loading equipment shall be maintained in good operating conditions and 

shall be operated in a manner to minimize emissions of air contaminants into the 

atmosphere.

4. No air contaminant shall be released into the atmosphere which causes a public 

nuisance or is in excess of any local, state or federal emission standard.

5. The hydrochloric acid trans-loading systems must not be operated unless it is 

vented to a fume scrubber. 

6. The Permittee shall perform an initial scrubber effluent gas source test 90 days 

after issuance of this permit to prove compliance with concentration emissions, 

mass emissions, and efficiency requirements. Test method shall have prior 

approval from the ICAPCD.

7. All HCL receiving, storage and usage activities shall be limited to a maximum 

HCL concentration of 36 wt% HCL.

J. Notification 

1. Breakdowns:

17
Salton Sea Power Generation, L.P. shall notify the ICAPCD (per Rule 111) of 

any upset conditions or breakdown (for all equipment) or scheduled maintenance 

(excluding any RTO and scrubber system or oxidizer box unit) which causes a 

violation of emission limitations prescribed by District Rules and Regulations, or 

by State law. The District shall be notified within as reasonably possible as but 

no later than two (2) hours after its detection. The completion of corrective

measures or the shutdown of emitting equipment is required within 24 hours of 

occurrence of a breakdown condition, unless an Emergency Variance has been 

obtained. Venting due to plant startup, load rejection, or well testing is not 

considered breakdown condition.

a. The Permittee shall notify the Air District within 2 hours of initiating 

unscheduled maintenance activities due to an upset condition or 

breakdown of any RTO and scrubber system or oxidizer box unit. 

2. Maintenance:

The Permittee shall notify the Air District at least 24 hours in advance before any

scheduled maintenance activity of any RTO and scrubber system or oxidizer

box unit. 

3. Modifications:

The Permittee shall notify the Air District of any material physical change, change 

in method of operation, or addition to the facility that results in a net emission 

increase or decrease of any regulated pollutant.

K. Monitoring Program 

1. The Permittee shall monitor the oxidizer boxes on a monthly basis as follows:

a. The control efficiency of the oxidizer boxes by measuring the hydrogen 

sulfide concentration in the condensate at the inlet and at the outlet (rain) 

of the oxidizer box. The hydrogen sulfide mass flow to the oxidizer box will 

be estimated and the abatement efficiency of the oxidizer box will be 

calculated by using the difference between the hydrogen sulfide inlet and 

outlet concentration.

b. The Permittee shall calculate the total hydrogen sulfide emissions at Units 

1 and 2, and Units 3 and 4 controlled gas RTO/scrubber stack and 

oxidizer boxes at each plant site.

2. The Permittee shall conduct a source test of the RTO and Scrubber System with 

the KinPactor Dust Collector at Units 1 and 2, and the RTO and Scrubber

System with the KinPactor Dust Collector at Units 3 and 4. The source tests of 

18
the RTO and Scrubber systems shall be conducted within the first month after 

the startup of the modified KinPactor Dust Collectors and every year thereafter or 

sooner if requested by the Air Pollution Control Officer, (APCO). The source 

testing shall use EPA methods or ICAPCD approved equivalent. Test protocol 

shall be submitted to the district for approval 30 days prior to source test being 

conducted.

a. The Permittee shall estimate the hydrogen sulfide and benzene control 

efficiency by measuring their concentration in the non-condensable gas at 

the inlet and at the outlet of the RTO and scrubber system.

b. The Permittee shall estimate the hydrogen sulfide and benzene mass flow 

emission rate in lb/hr vented from RTO stack before the scrubber. 

c. The Permittee shall estimate the scrubber control efficiency for SO2 by 

measuring the concentration in the non-condensable gas at the outlet of 

the RTOs and at the outlet of the Scrubbers. PM10 will be measured at the 

outlet of the scrubbers using approved test methods.

d. The Permittee shall calculate a mass balance within the regulated 

pollutants controlled in the RTO/Scrubber system.

e. The Permittee shall ensure that the source test is carried out under 

representative operating parameters and conditions. 

3. The Permittee shall monitor Units 1 and 2, and Units 3 and 4 controlled gas 

RTO/scrubber system as follows: 

a. The RTO Unit Combustion Chamber operating temperature shall be 

continuously monitored and data logged every (5) minutes.

b. The scrubber operation parameters of the scrubber water as re-circulation 

flow rate and pH shall be logged every five (5) minutes.

c. The Permittee shall monitor on a weekly basis the hydrogen sulfide and 

benzene at the inlet and at the outlet of the RTO.

i. The Permittee shall estimate the hydrogen sulfide and benzene mass 

flow emission rate in lb/hr and lb/day vented from the RTO. The NCG 

flow rate shall be determined by plant flow-meters. 

ii. The Permittee shall calculate the RTO control efficiency by measuring 

hydrogen sulfide and benzene concentration in the non-condensable 

gas at the inlet of the RTO and the outlet of the scrubber.

iii. The Permittee shall estimate the scrubber control efficiency for sulfur 

19
dioxide by measuring ppmv sulfur dioxide concentration in the noncondensable gas at the inlet and at the outlet of the scrubber. 

4. The Permittee shall conduct a cooling tower H2S source test of the facility within 

the third quarter of 2010 and every four years thereafter or sooner if requested by 

the Air Pollution Control Officer, (APCO). The source test shall be conducted in 

the cooling tower shrouds at each facility in Region 1 for Units 1, 2, 3, 4 and 5. 

The source testing shall use EPA methods or ICAPCD approved equivalent (for 

hydrogen sulfide, ARB method 102 modified for Imperial County with NH3 filter 

shall be utilized). Testing protocol shall be submitted to the district for approval 

30 days prior to source testing being conducted. Testing every 4 years shall 

include the constituents identified in Section M.3 and shall be conducted as 

follows:

a. Total emissions from each cooling tower shall be estimated in accordance 

with EPA/ARB approved methods (for PM10, EPA AP-42 emission factors

shall be utilized to calculate emissions).

b. A 30-day advance notification of testing dates shall be provided to the 

APCD for scheduling.

5. The Permittee, within 30 days of the end of each month, shall calculate the 

previous month’s total hydrogen sulfide emissions for Region 1, and add it to the 

preceding 11 months to get a twelve 12 month total. These calculations shall be 

maintained in a log and made available to the APCD upon inspection in order to 

demonstrate compliance with the emissions limit set forth in Condition E.4 and 

E.2. 

6. The Permittee, within 30 days of the end of each month, shall calculate the 

previous month’s total PM10 emissions for Region 1, and add it to the preceding 

11 months to get a twelve 12 month total. These calculations shall be 

maintained in a log and made available to the APCD upon inspection in order to 

demonstrate compliance with the emissions limit set forth in Condition B.3.

7. The owner of a Source operation, when requested by the Air Pollution Control 

Officer, shall provide records, collect samples or gather other required 

information that which will enable the Air Pollution Control Officer to determine 

compliance status (Rule 109). The APCD may at any time elect to have itself or a 

third party source test contractor or agency take samples and analyze for 

concentration and emission rates of any pollutant.

8. All the source testing, sampling, analysis and reporting cost shall be borne by the 

Permittee.

9. Upon proper notification, the APCD or its designee shall have the right to enter, 

inspect and take samples from Region 1 power plants emissions sources.

20
L. Analyses 

1. The Permittee shall conduct monthly analysis of hydrogen sulfide content in the 

condensate at the inlet and at the outlet of the oxidizer boxes using EPA 

methods or equivalent.

2. In accordance with Section K.2, the source test of each RTO and scrubber 

system (and KinPactor Dust Collector) shall use laboratory analysis EPA/ARB 

approved methods or ICAPCD approved equivalent for the following: Of the RTO 

scrubber stack gas exhaust for: hydrogen sulfide, benzene, ammonia, sulfur 

dioxide, NOx, and PM10. Testing protocol shall be submitted to the district for 

approval 30 days prior to source testing. All analysis results shall be submitted to 

APCD within 60 days of testing, also results shall be available at the facility for 

inspection.

3. In accordance with Section K.4, the Permittee shall conduct a source test of the 

Region 1 facility in the year 2010 and every four years thereafter or sooner if 

requested by the APCO to ensure compliance. The source test shall be 

witnessed by APCD staff. All analysis results shall be submitted to APCD within 

90 days of testing, also results shall be available at the facility for inspection. 

Laboratory analysis shall use EPA approved methods or an ICAPCD approved 

equivalent for the following:

a. Source test protocol of year 2010 shall be submitted for APCD approval 

30 days prior to source testing being conducted including testing 

described in Sections K.4, above. 

b. Hot well condensate from the turbine condensers and cooling tower blowdown for ammonia, arsenic, benzene, cadmium, chromium, copper, 

hydrogen sulfide, lead, manganese, mercury, nickel, radon, selenium and 

zinc.

c. Of the non-condensable gases vented for: hydrogen sulfide, ammonia, 

arsenic, mercury, radon, benzene, toluene, and xylene.

4. The Permittee shall conduct weekly analysis at Units 1 and 2, and Units 3 and 4 

for hydrogen sulfide and benzene content in the non-condensable gases at the 

inlet of the RTO system and the outlet of the scrubber, using EPA methods or 

equivalent.

5. The Permittee shall conduct weekly analysis of sulfur dioxide content in the noncondensable gases at the inlet and at the outlet of the scrubber using EPA/ARB 

methods or equivalent.

21
6. The Permittee shall conduct bi-weekly (twice per month) testing of the 

recirculating water total dissolved solids levels for each cooling tower units at 

Region 1 to verify compliance with the Region 1 cooling tower PM10 emission 

limit in Condition H.1. 

M. Reports 

1. The Permittee shall submit to the ICAPCD a monthly report within 30 days of the 

preceding month’s end to include oxidizer boxes abatement efficiency of 

hydrogen sulfide. The report shall also include the hydrogen sulfide concentration 

in the condensate at the inlet and outlet (rain) of the oxidizer box in mg/l and the 

hydrogen sulfide mass flow in lb/hr based on the monitoring and analysis 

conducted pursuant to the requirements of Section K.1 and L.1.

2. The Permittee shall submit to the ICAPCD a report containing the RTO and 

scrubber source test pursuant Sections K.2 and L.2. The report shall be 

submitted 60 days after the source testing completion and as required by the 

APCD to ensure compliance. 

3. The Permittee shall submit to the ICAPCD a monthly report within 30 days of the 

preceding month’s end to include all the result analysis of hydrogen sulfide, 

benzene and sulfur dioxide analysis. Report the abatement efficiency of the RTO 

and scrubber. Hydrogen sulfide, sulfur dioxide and benzene of the RTO and 

scrubber stack mass flow emission rate in lbs/hr based in the analysis conducted 

pursuant to the requirements of Section K.3 and L.4 and L.5.

4. The Permittee shall submit to the ICAPCD a report containing the cooling tower 

source testing pursuant to Section K.4 and L.3. The report shall be submitted 90 

days after the source testing completion and every four years thereafter or as 

required by the APCD to ensure compliance. 

a. Analyses conducted pursuant to the requirements of Section K.4 and L.3 

above.

b. Based on analyses conducted in Section K.4 and L.3 and the emissions 

derived from the analyses, an emission inventory for the facility showing 

compliance with permit limits.

5. The Permittee shall submit to the ICAPCD a monthly report within 30 days of the 

preceding month’s end which includes the total cumulative hydrogen sulfide 

emissions of Region 1 from each preceding twelve (12) month period.

6. The Permittee shall submit to the ICAPCD a monthly report within 30 days of the 

preceding month’s end which includes the total cumulative PM10 emissions of 

Region 1 from each preceding twelve (12) month period. This report shall 

22
include a section of the evaluation of the total PM10 emissions from all cooling 

towers at Region 1, pursuant to the TDS testing requirement of Section L.6. 

7. The Permittee shall submit to the ICAPCD an annual report by the end of 

February of each operating year. This report shall include the following items:

a. Total tons of hydrogen sulfide, benzene, and PM10 emissions for the 

reporting year.

b. Types and quantities of cooling water additives.

c. Results from each month’s test of the recirculating water total dissolved 

solids levels for each cooling tower unit.

d. Net electrical megawatt-hours sold for the report year.

e. Total hours of operation of each Units 1 through 5.

f. Total maintenance program hours, pursuant to Conditions C.1 and C.2.

g. For each standby emergency generator and additional stationary engines 

used, the total hours of operation for each engine, and the calculated total 

fuel used by each engine.

h. The status of all active wells associated with this facility used for 

production or injection during the report year. For each well include the 

total days of rig activity (work over, clean out or drilling); and the total 

hours of venting to the atmosphere (from test units).

8. Within 10 days after a breakdown occurrence has been corrected, the Permittee 

shall submit a written report to the APCO which includes: 

a. A statement that the occurrence has been corrected.

b. The reason(s) or cause(s) of the occurrence. 

c. A description of the corrective measures undertaken.

d. The type of emission and estimated quantity of the emissions caused by 

the occurrence. 

9. Emissions in excess of those pursuant under 40 CFR Part 70.2 defined under 

Rule 900 B.20 of the Imperial County APCD Rules and Regulations shall require 

the facility to obtain a Title V permit.

10. In carrying out the maintenance program for the RTO and scrubber systems and 

oxidizer box units described in Section C.2 and F.2, the Permittee shall record 

and submit the following:

a. An operational log, which shall be maintained and kept for a minimum of 

three years, to track periods of maintenance for each unit. 

b. The Permittee shall report all maintenance hours in the monthly report for 

the month during which the maintenance activities occurred.

N. Emergency Units

23
1. Each listed emergency generator shall be restricted to operate a total of 20 

(twenty) hours per year for maintenance and testing purposes.

2. The listed emergency fire pump shall be restricted to operate a total of 35 (thirtyfive) hours per year for maintenance and testing purposes and to comply with the 

requirements of the National Fire Protection Association (NFPA) 25. 

3. Each listed emergency combustion unit shall be restricted to operate a maximum 

of 1 (one) hour per day for testing and maintenance purposes. 

4. The Unit 5 Standby Power Generator shall not operate for maintenance and 

testing purposes on the same day as the other Region 1 emergency combustion 

units.

5. Operation of the emergency power generator for other than testing and 

maintenance purposes, shall be limited to provide backup power, in each 

instance, be documented to the satisfaction of the ICAPCD.

6. All internal combustion engines shall not discharge into the atmosphere any 

visible air contaminant other than uncombined water vapor, for a period or 

periods aggregating more than three minutes in any one hour, which is 20% 

opacity or greater.

7. Each unit, with an internal combustion engine rated greater than 50 horsepower, 

shall have installed a non-resettable hour meter. The device shall be kept in 

proper working condition at all times.

8. The permittee shall maintain an operation engine log onsite for each listed unit 

with an internal combustion engine rated greater than 50 horsepower. The 

Permittee shall maintain all required records for a minimum of two (2) calendar 

years and make them available to the ICAPCD upon request. The log(s) shall 

include the following for each unit:

a. Engine manufacturer name, model number, brake horsepower output 

rating, and type of fuel combusted;

b. A manual of recommended maintenance as provided by the engine 

manufacturer or other maintenance procedure as approved in writing by 

the APCO;

c. Record of routine engine maintenance, including date(s) and type of 

maintenance performed;

d. A specific emission inspection procedure, with an inspection schedule, to 

ensure that the engine is operated in continual compliance with Air District 

Rule 400.3. Inspections shall be conducted every quarter or after every 

2,000 hours of engine operation. In no event shall the frequency of 

inspections be less than once per year.

24
e. For each emergency unit, the total daily recorded hours of operation for 

maintenance and testing purposes.

f. For each emergency unit, the total daily recorded hours of operation for 

emergency events.

9. The listed Detroit Diesel emergency generators, with Engine Model 71237305,

shall be limited to the following emission limits:

a. 20.0 lbs/hr of NOx.

b. 4.0 lb/hr of CO.

10. The listed 1200 kW Detroit Diesel emergency generator shall be limited to the 

following emission limits:

a. 37.4 lbs/hr of NOx.

b. 14.0 lb/hr of CO.

11. The Permittee shall conduct an initial source test for each listed emergency

generator to demonstrate compliance with the emission limits of Conditions N.9

and N.10 by October 4, 2014 and once every 60 months thereafter.

12. The listed emergency generators shall each be source tested at least at 80% of 

the total horse power rating to determine compliance with the emission limits of 

Conditions N.9 and N.10. If the permittee demonstrates to the satisfaction to the 

APCO that a listed unit cannot operate at 80% capacity, then the source test 

shall be performed at the highest achievable continuous power rating. 

Compliance with the NOx emission limits shall be determined by using CARB 

Method 100 or US EPA Method 7E. Oxygen Content shall be determined by 

using CARB Method 100 or US EPA Method 3A. Compliance with the CO 

emission limits shall be determined by using CARB Method 100 or US EPA 

Method 10. 

13. The source test protocol for each required test of Condition N.11 shall be 

submitted to the ICAPCD for approval 30 days prior to commencing testing. The 

source test results shall be submitted to the ICAPCD within 60 days of the test 

being completed. 

O. Miscellaneous Combustion Sources

1. Other miscellaneous stationary diesel and/or gas-fired internal combustion 

sources for various plant and well field activities not included under this permit. 

Each miscellaneous source is limited to operate pursuant the ATCM Rules.

25
Equipment List

Standby Power Equipment

Unit 1&2:

1. One Standby Power Generator Set, 425 KW, Detroit Diesel Engine, Model 

71237305, 575 HP @ 1800 RPM. 

Unit 3&4:

1. One Standby Power Generator Set 425 KW, Detroit Diesel Engine, Model 

71237305, 575 HP @ 1800 RPM. 

2. One 300 HP Model 3306 16844 CAT Diesel Fire Pump

Unit 5: 

1. One Standby Power Generator Set, 1200 KW, Detroit Diesel, Model 

743FSM2304AP-000W 

Lime Slaker Equipment at Unit 5 Grounds

1. ZMI Porter M-40 Lime Slaking unit rated at 9000 lbs/hr (4.5 tons/hr), 7 9/16 HP 

motors.

2. 2200 cu. ft. dry lime silo

3. Grit shaker and discharge conveyor assembly

4. DF-48 Dust Collector, 1176 cfm max. capacity, 295 sq. ft. bag area.

H2S and Benzene Control Equipment

Facilities NCG H2S Condensate H2S

Unit 1 and 2 RTO/Scrubber 2 oxidizer boxes

Unit 3 and 4 RTO/Scrubber 2 oxidizer boxes

Unit 5 None 

Power Units Capacity

Unit 1 and 2 30.0 MW 

Unit 3 and 4 95.0 MW 

Unit 5 49.9 MW 

 Total Installed Capacity 175.9 MW

Acid Trans-loading

26
1. HCL Wet Scrubber ID TK-3201, 35 GPM; 10 feet packing height. 

PM10 Control Equipment 

Unit 1&2:

1. One (1) American Air Filter (AAF) KinPactor System, Design 2 and Size 8. The 

system includes one new Zeron 100 Alloy cyclone separator, Size 75, and one 

fan setup to handle 7,500 acfm at 35” SP.

Unit 3&4:

1. One (1) American Air Filter (AAF) KinPactor System, Design 2 and Size 8. The 

system includes one new Zeron 100 Alloy cyclone

Recommendations

The Air District made the preliminary decision to issue an Authority to Construct (ATC) 

to the CalEnergy Operating Corporation (CalEnergy) for the proposed equipment 

modification at the Region 1 Geothermal Power Plant Facility, located west of Calipatria, 

CA. Per the requirements of Air District Rule 206.C, this permit application is being 

processed as a Discretionary Permit due to the stationary source’s modified Potential to 

Emit (PTE) for the pollutants NOx, PM10, SO2, and H2S each being greater than 100 

pounds per day.

Since the application is classified as a Discretionary Permit, the Air District issued a 

written preliminary decision approving this proposed project, and the application and Air 

District evaluation was available to the public for review and commenting for a period of 

30 days. After determining that the Air District did not receive any written comments 

during the 30-day period, which closed on March 2, 2015, the final decision was made 

to proceed with the issuance of ATC 2000H-9 to CalEnergy for the proposed 

modification.

Permit Fees

Geothermal Resource Production/Utilization Facility 

Rule 302, Schedule 6 – Geothermal Schedule:

27
Power Plants Capacity Fee per MW 2015 Fees

Units 1 and 2

Units 3 and 4

Unit 5

27.0 MW

94.0 MW

51.0 MW

$301.00

$301.00

$301.00

$8,127.00

$28,294.00

$15,351.00

Total: $51,772.00

Standby Equipment 

Rule 302, Schedule 9 – Miscellaneous Schedule:

2015 Fee: ($180.50 x 4 emergency standby units) = $722.00

RTO and Scrubber Systems

Rule 302, Schedule 9 – Miscellaneous Schedule:

2015 Fee: ($180.50 x 2 RTO/scrubber systems ) = $361.00

Lime Slaker

Rule 302, Schedule 1 – Electric Motor Horsepower Schedule

Up to and including 25 (hp) = $261.50

Total Operating Fee: ($51,772.00 + $722.00 + $361.00 + $261.50) = $53,116.50

2015 Operating Fee = $53,116.50

28