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George Washington University Proposed Air Quality Permit for Installation of a Cogeneration Facility

Fiscal Year 2013
Notice of Public Comment Period

Notice is hereby given that, pursuant to 40 C.F.R. Part 51.161, and D.C. Official Code §2-505, the Air Quality Division (AQD) of the District Department of the Environment (DDOE) located 1200 First Street NE, Washington, DC, intends to issue an air quality permit (#6618) to the George Washington University for installation and subsequent operation of a combined heat and power system at Ross Hall on the Foggy Bottom Campus, located at 24th and H Streets NW, Washington DC. The contact person for the facility is Doug Spengel, Energy and Environmental Manager, Facilities Services at (202) 994-6067.  The facility’s mailing address is 2025 F Street NW, Washington DC 20052.

The proposed equipment is as follows:

- Combined Heat and Power (CHP) Emission Units:

  • One (1) Solar Centaur 50-T6200S Combustion Gas Turbine (CT) rated at 52.9 MMBtu/hr heat input firing natural gas (NG) only; and
  • One (1) Cleaver Brooks Slant Series S4-2816 Heat Recovery Steam Generator (HRSG) equipped with supplemental firing by NATCOM Duct Burner rated at 18.9 MMBtu/hr heat input , firing NG;

- CHP Ancillary Equipment and Appurtenances:

  • One (1) 4,600 kW Centaur 50 Gas Turbine Generator;
  • One (1) 24,500 lb/hr Water Tube Steam Boiler for the HRSG;
  • One (1) 2,974 lbm/hr Deaerator;
  • One (1) Water Treatment System;
  • One (1) Heat Exchanger for Condensate Return; and
  • One (1) Existing Steam – Receiving Turbine Generator.

The proposed overall emission limits for the equipment are as follows:
The Permittee shall not exceed the emission limits in the following tables as applicable:

Table 1: Total 12-Month Rolling Emission Limits from Permitted Equipment1


12-Month Rolling Emissions Limit

(tons/12 mo. rolling period)

Particulate Matter (PM) (Total)2,3


Oxides of Sulfur (SOx)


Oxides of Nitrogen (NOx)


Volatile Organic Compounds (VOC)


Carbon Monoxide (CO)


1. The equipment covered consists of one Solar Centaur 50 gas turbine, and one HRSG/duct burner.
2. PM (Total) is the sum of the filterable PM and condensable PM.
3. All PM is expected to be smaller than 2.5 microns, so PM (Total) equals PM2.5

Table 2- Maximum Hourly Emissions (lbs/hr) when Operating Between 50% and 100 % Load, Inclusive


Solar Centaur 50 Gas Turbine (CT) and  HRSG/Duct Burner (HDB)

PM (Total)










A.   Visible emissions shall not be emitted into the outdoor atmosphere from the emission units and control equipment, except that discharges not exceeding forty percent (40%) opacity (unaveraged) shall be permitted for two (2) minutes in any sixty (60) minute period and for an aggregate of twelve (12) minutes in any twenty-four hour (24 hr.) period during start-up, cleaning, adjustment of combustion controls, if any, or malfunction of the equipment [20 DCMR 606.1].

B.   Violation of standards set forth in Condition II(b)(1), as a result of unavoidable malfunction, despite the conscientious employment of control practices, shall constitute an affirmative defense on which the discharger shall bear the burden of proof.  Periods of malfunction shall cease to be unavoidable malfunctions if reasonable steps are not taken to eliminate the malfunction within a reasonable time.  [20 DCMR 606.4]

C.  Where the presence of uncombined water is the only reason for failure of an emission to meet the requirements of Condition II(b)(1), Condition II(b)(1) shall not be applicable. [20 DCMR 606.6]

D.   An emission into the atmosphere of odorous or other air pollutants from any source in any quantity and of any characteristic, and duration which is, or is likely to be injurious to the public health or welfare, or which interferes with the reasonable enjoyment of life or property is prohibited. [20 DCMR 903.1] Note: This condition is District enforceable only.

The proposed emission limits specific to the combustion gas turbine are as follows:

A.  Particulate emissions (total filterable only) from the gas combustion turbine shall not exceed 0.069 pound per million Btu. [20 DCMR 600.1]

B.  Sulfur dioxide (SO2) emissions from the gas turbine shall not exceed 0.060 lb SO2/MMBtu heat input for each calendar month when natural gas is burned. [40 CFR 60.4330]:

C.  NOx emissions from the turbine without supplemental firing shall not exceed 15 ppmvd at 15% O2. [40 CFR 60.4320 and 60.4325 and 20 DCMR 201] 

D.  NOx emissions from the turbine when fired with supplemental duct burner firing shall not exceed 18 ppmvd at 15% O2.  [40 CFR 60.4320 and 60.4325 and 20 DCMR 201]

The proposed emission limits specific to the heat recovery steam generator (HRSG) and duct burners are as follows:

A.  The HRSG/Duct Burner (HDB), shall not emit pollutants in excess of 0.1 lb NOx/MMBtu. [20 DCMR 201]

B.  Particulate emissions (total filterable only) from the HDB shall not exceed 0.087 pounds per million Btu. [20 DCMR 600.1]

C.  Sulfur dioxide emissions shall not exceed 0.060 lb SO2/MMBtu heat input. [40 CFR 60.4305 and 40 CFR 60.4330(a)(2)]

D.  NOx emissions from the Combustion Turbine/HDB (CT/HDB) train exhaust (while supplemental firing with duct burner) shall not exceed 18 ppmvd at 15% O2 as required by Condition III(a)(1)(E). [20 DCMR 201 and 40 CFR 60.4320]

E.   NOx emissions from CT/HDB train shall not exceed 5.2 lb/hr as measured at the HRSG exhaust. [20 DCMR 201]

The permit applications and supporting documentation, along with the draft permits and the Department’s analyses of the applications are all available for public inspection at AQD and copies may be made available between the hours of 8:15 A.M. and 4:45 P.M. Monday through Friday.  Interested parties wishing to view these documents should provide their names, addresses, telephone numbers and affiliation, if any, to Stephen S. Ours at (202) 535-1747.

Interested persons may submit written comments or may request a public hearing on this subject within 30 days of publication of this notice.  The written comments must also include the person’s name, telephone number, affiliation, if any, mailing address and a statement outlining the air quality issues in dispute and any facts underscoring those air quality issues.  All relevant comments will be considered in issuing the final permit.

Comments on the proposed permit and any request for a public hearing should be addressed to:

Stephen S. Ours - Chief, Permitting Branch

District Department of the Environment - Air Quality Division
1200 First Street NE, 5th Floor
Washington DC 20002

[email protected]

No written comments postmarked after December 24, 2012 will be accepted.

For more information, please contact Stephen S. Ours at (202) 535-1747.