CITY OF PHILADELPHIA

Department of Public Health 

Environmental Protection Division 

Air Management Services 

InterOffice Memo 

To: File 

From: Biji Pandisseril & Edward Wiener 

Date: August 29, 2014 

Subject: 1997 8-Hour RACT Analysis for Philadelphia Gas Works- Richmond (PLID # 04922) 

Introduction: 

The Clean Air Act (CAA) requires that moderate (or worse) ozone nonattainment areas implement reasonably 

available control technology (RACT) controls on all major sources of Volatile Organic Compounds (VOC) and 

Nitrogen Oxides (NOx). Philadelphia County is part of the Philadelphia-Wilmington-Atlantic City moderate ozone 

nonattainment area for the 1997 8-hour ozone National Ambient Air Quality Standards (NAAQS). This document 

presents the findings of a RACT evaluation for the 1997 8-hour ozone standard for this facility.

Company Description: 

Philadelphia Gas Works (PGW) - Richmond Plant owns and operates a natural gas utility at 3100 East Venango 

Street in Philadelphia, Pennsylvania. 

Applicability for NOx and VOC RACT: 

PGW Richmond is a major source of NOx having potential NOx emissions greater than 100 tons per year, the major 

source threshold in Philadelphia County that is applicable to NOx RACT under the 1997 8-hour ozone NAAQS. The 

facility is not a major source of VOC having potential VOC emissions of less than 50 tons per year, the major source 

threshold in Philadelphia County that is applicable to VOC RACT under the 1997 8-hour ozone NAAQS. 

The facility is subject to RACT under the 1-hour ozone NAAQS. As a result of a 1-hour RACT determination, 

AMS issued the1-hour RACT Plan Approval (PA Permit Number 51-4922) dated July 26, 1999 for PGW - 

Richmond, which was approved by EPA as part of the State Implementation Plan (SIP) on October 31, 2001 (66 FR 

54947). 

Process Descriptions: 

The emissions units in PGW Richmond include the following: six (6) Liquefied Natural Gas (LNG) vaporizer 

heaters between 94.1 and 105.0 MMBTU/hr, five (5) boiler/heaters of 11 MMBTU/hr or less(H-2 Boiloff Heater, H3 Regen Gas Heater, Uniflux/Exotherm (26), GasMaster Boiler (19A-1), and Gas Master Boiler (19B-1)), four (4) 

simple cycle combustion turbines of 13.7 MMBTU/hr or less (two Solar Gas Turbine compressor and two Solar gas 

turbine electric generators), two (2) 170 HP emergency generators,, and three (3) Catrepillar 295 HP engines for fire 

pumps. These are the only NOx emission sources at the facility. 

RACT Analysis: 

Shut Down Units 

At the time of the 1-hour RACT analysis, the facility also had four Clark engines, two Clark Stand-by engines, two 

Ingersoll-Rand stand-by boil-off compressors, two Kewanee boilers, two facility heaters, and two AO Smith Undertank heating system, but since then these sources have shut down are not listed in the current Title V operating 

permit for the facility (No. V11-034). 

Case-by-case RACT 
The four Clark engines were subject to case-by-case RACT requirements under 1-hour RACT. These requirements 

are no longer applicable as these units have been shut down and permanently removed from the facility. 

AMS is requesting to remove the applicable requirements for these units from the 1-hour RACT plan approval. 

Presumptive RACT 

In accordance, with 25 PA Code 129.93 (a) all of the remaining sources at the facility are subject to presumptive 

RACT limitations. 

The facility complies with the presumptive RACT requirements of 25 PA Code 129.93(c)(5) for the large LNG 

Vaporizer Heaters by operating the heaters to less than 5% annual capacity. To ensure compliance with the 5% 

annual capacity, the heaters are limited to a total combined annual natural gas usage of 257 MMcf/yr. These 

requirements are part of the SIP-approved 1-hour RACT. 

The five boilers/heaters (H-2 Boiloff Heater, H-3 Regen Gas Heater, Uniflux/Exotherm (26), GasMaster Boiler 

(19A-1), and Gas Master Boiler (19B-1)) are less the 20 MMBTU/hr and comply with 25 PA Code 129.93(c)(1) 

presumptive RACT requirements for installation, maintenance, and operation in accordance with manufacturers 

specifications. 

The four single cycle combustion turbines (two Solar Gas Turbine compressor and two Solar gas turbine electric 

generators), which are less than 25 MMBTU/hr and are used for natural gas distribution, will comply with the 

presumptive RACT 25 PA Code 129.93(c)(2) by installing, maintaining, and operating in accordance with 

manufacturers specifications. 

Each emergency generator complies with presumptive RACT 25 PA Code 129.93(c)(5) by operating less than 500 

hours in consecutive 12-month period. 

Each of the 294 HP engines for fire pumps complies with presumptive RACT 25 PA Code 129.93(c)(5) by operating 

less than 500 hours in consecutive 12-month period. 

The following removed sources were also subject to presumptive RACT requirements: two (2) Clark stand-by 

engines and, two (2) Ingersoll-Rand standby boil-off compressors. AMS is requesting to remove the applicable 

requirements for these units form the 1-hour RACT. 

Summary Table - Applicable Presumptive RACT 

Sources Presumptive RA CT 

Six (6) Vaporizer Heater between 94.1 and 105.0 MMBTU/hr 25 PA Code 129.93(c)(5) 

Two (2) Heater 11 MMBTU/hr or less 25 PA Code 129.93(c)(1) 

Four (4) turbines 13.7 MMBTU/hr or less three 25 PA Code 129.93(c)(2) 

Three (3) boilers/heater less than 10 MMBTU/hr 25 PA Code 129.93(c)(1) 

Three (3) 295 HP engines for fire pumps 25 PA Code 129.93(c)(5) 

Two (2) 170 HP emergency generators 25 PA Code 129.93(c)(5) 

Conclusions and Recommendations: 

The case-by-case requirements under the previous 1-hour RACT determination are no longer applicable, since 

sources subject to these requirements have been shutdown. All existing sources at the facility are covered 

by presumptive RACT. AMS proposes these requirements continue to represent RACT under the 1997 8-hour 

ozone standard.. 

Changes to the SIP-approved 1-hour RACT 

AMS is requesting changes to the 1-hour RACT to remove any requirements for shutdown sources. 

(Strikethrough is used to show requirements to be removed) 
1. The purpose of this Plan Approval is to establish Nitrogen Oxides (NOx) Reasonably Available Control

Technology (RACT) for PGW This includes the following emission sources and control equipment:

A. Emission Sources:

Unit Description Fuel Type Full Rated Capacity

Four Clark HLA -8T (C2A, C2B, C3A, C3B) Natural Gas 2,350 horsepower

LNG vaporization Heater Natural Gas 94.1 MMBTU/hr 

LNG vaporization Heater Natural Gas 94.1 MMBTU/hr 

LNG vaporization Heater Natural Gas 96.6 MMBTU/hr 

LNG vaporization Heater Natural Gas 102.1 MMBTU/hr 

LNG vaporization Heater Natural Gas 105.0 MMBTU/hr 

LNG vaporization Heater Natural Gas 105.0 MMBTU/hr 

Two Standby Clark HLA -8T (C1A, C1B) Natural Gas 2,350 horsepower

Two Standby Ingersoll-Rand boiloff compressors KVG-83FL/HL Natural Gas 800 horsepower 

B. Control Equipment

(1) Four Clark HLA -8T 2,350 horsepower Units (C2A, C2B, C3A, and C3B) shall be retrofitted with new 

high energy ignition systems, AFR controls, a turbocharger system enhancement along with new fuel 

valves. 

(2) Limit the following units’ operating schedule to five percent of their maximum operating capacity: 

LNG vaporization Heater 94.1 MMBTU/hr 

LNG vaporization Heater 94.1 MMBTU/hr 

LNG vaporization Heater 96.6 MMBTU/hr 

LNG vaporization Heater 102.1 MMBTU/hr 

LNG vaporization Heater 105.0 MMBTU/hr 

LNG vaporization Heater 105.0 MMBTU/hr 

Two Standby Clark HLA -8T 2,350 horsepower (C1A, C1B) Units

Two Standby Ingersoll-Rand boiloff compressors KVG-83FL/HL 800 horsepower Units

2. This approval requires and authorizes: 

A. Four Clark HLA -8T 2,350 horsepower units, respectively C2A, C2B, C3A and C3B shall be retrofitted 

with new high-energy ignition systems, AFR controls, a turbocharger system enhancement along with new 

fuel valves.

B. Based on a rolling 12-month period, the annual fuel consumption for the four Clark HLA -8T 2,350 

horsepower units shall be limited to 570 MMCF of natural gas. 

C. PGW shall comply with the requirements as specified in the RACT requirements of 25 PA Code 

129.91(f); pertaining to expeditious compliance. 

D. The following sources shall comply with presumptive RACT requirement requirements of 25 PA Code 

129.93(c)(5): 

(1) Calculated on a 12-month rolling period the total annual fuel usage for the Six LNG vaporization

Heaters 103 MMBTU/hr Units is limited to 257 MMCF of natural gas.

(2) Calculated on a 12-month rolling period, the annual fuel usage for the Two Standby Clark HLA -8T 

2,350 horsepower (C1A, C1B) Units shall be limited to 14.8 MMCF of natural gas.

(3) Calculated on a 12-month rolling period, the annual fuel usage for Two Standby Ingersoll -Rand 

boiloff compressors KVG-83FL/HL 800 horsepower Units is limited to 6.7 MMCF of natural gas.

3. Emission Limitations:
A. The maximum air contaminant emissions from the equipment listed in the “Sources” section of this RACT 

Permit shall have the following limitations:

(1) Nitrogen Oxides (NOx):

a) Each of the four Clark HLA -8T 2,350 horsepower units (C2A,C2B, C3A, C3B ) shall have 

individual stack emission limitations of 5grams per Brake Horse Power per Hour for Oxides of 

Nitrogen (NOx). Compliance with these limitations shall be demonstrated by using appropriate 

emission calculation procedures which are approved by AMS. (See 5.Testing Requirements).

b) Each of the four Clark HLA -8T 2,350 horsepower units (C2A,C2B, C3A, C3B) shall have 

individual stack emission limitations of 25.9 lbs. of Oxides of Nitrogen (NOx) per hour. Compliance 

with these limitations shall be demonstrated by using appropriate emission calculation procedures, 

which are approved by AMS. (See 5.Testing Requirements).

c) The four Clark HLA -8T 2,350 horsepower units (C2A, C2B, C3A, and C3B) shall have a total 

emission limitation of 320 tons of Oxides of Nitrogen (NOx) per year, calculated on a 12-month 

rolling period. Compliance with these limitations shall be demonstrated by using appropriate emission 

calculation procedures that are approved by AMS. (See 5.Testing requirements)

4. RACT Implementation Schedule: 

A. Upon issuance of this approval, PGW shall begin immediate implementation of the measures necessary to 

comply with this RACT permit. 

B. PGW shall operate NOx controls on the Four Clark HLA_8T Units (C2A, C2B, C3A, and C3B) by May 

31, 1997.

5. Testing Requirements: 

A. PGW must conduct performance testing on the Four Clark HLA_8T Units (C2A,C2B, C3A, and C3B) 

once every five years to demonstrate compliance with this RACT permit. Compliance testing shall be 

performed between the calendar period of July 1 and September 1 of each scheduled test year.

B. PGW shall submit to AMS a proposed stack testing protocol at least (60) days prior to the scheduled date 

for that stack testing.

C. If at any time AMS has cause to believe that air contaminant emissions from any source(s) listed in 

Section A of this permit may be in excess of the limitations specified in this permit, or established 

pursuant to, any applicable rule or regulation contained in 25 PA Code Article III, the Permittee shall be 

required to conduct whatever tests are deemed necessary by AMS to determine the actual emission rate(s). 

6. Monitoring Requirements: 

A. Engine mapping conducted in conjunction with the initial compliance testing of the Clark HLA-8T 2350 

horsepower units shall be used to establish coefficients for the control algorithms of each engine, including 

air/fuel ratio, ignition timing and air manifold temperature control.

No changes are proposed in Conditions 7 through 9. 

1/9/15

Edward Wiener, Chief of Source Registration Date