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Proposed Air Quality Permit 6347-R2 - District of Columbia Water and Sewer Authority

Friday, December 8, 2017


Proposed Air Quality Permit 6347-R2, District of Columbia Water and Sewer Authority (DC Water), Operation of an existing Enhanced Nitrogen Removal System (ENR) at Blue Plains Wastewater Treatment Plant, 5000 Overlook Ave SW

Notice is hereby given that, pursuant to 40 C.F.R. Part 51.161, D.C. Official Code §2-505, and 20 DCMR §210, the Air Quality Division (AQD) of the Department of Energy and Environment (DOEE), located at 1200 First Street NE, Washington, DC, intends to issue Permit No. 6347-R2 to the District of Columbia Water and Sewer Authority (DC Water) to operate the listed Enhanced Nitrogen Removal (ENR) equipment, located at 5000 Overlook Avenue SW, Washington DC 20032. The contact person for the facility is Meena Gowda, Principal Counsel, at (202) 787-2628.

ENR Equipment to be Permitted

The equipment consists of the following significant components:

  • Denitrification Carbon Storage and Feed System:
    • Two (2) new Denitrification Carbon Methanol Vapor Scrubbers (DCMVS 1 and 2);
    • Four (4) new 60,000 gallon Denitrification Carbon Storage Tanks (DCST 1, 2, 3, and 4);
    • Three (3) Denitrification Carbon Storage Tanks Mixing Pumps;
    • Four (4) Denitification Carbon Feed Pumps; Four (4) Denitrification Carbon Transfer Pumps;
    • Eight (8) Denitrification Reactors and two (2) post aeration tanks; and
    • Three (3) Methanol Unloading Pumps.
  • Alternate Carbon Storage and Feed System:
    • Two (2) new Alternate Carbon Methanol Vapor Scrubbers (ACMVS 1 and 2);
    • One (1) new 30,000 gallon Alternate Carbon Storage Tank (ACST-1);
    • Two (2) Alternate Carbon Unloading Pumps; and
    • Five (5) Alternate Carbon Mixing and Transfer Pumps.
  • Blended Alternate Carbon (BAC) Storage and Feed System:
    • Three (3) Blended Alternate Carbon Mixing Pumps;
    • Two (2) Blended Alternate Carbon Transfer Pumps;
    • Two (2) new Blended Alternate Carbon Feed Pumps;
    • One (1) 30,000 gallon Alternate Carbon Blend Storage Tank (ACST-2);
    • Three (3) 10,000 gallon Blended Alternate Carbon Storage Tanks (MST 5, 6, and 7) for storage of methanol or a blend (already existing);
    • and One (1) 650 gallon day tank for use with BAC or methanol (already existing).

      The primary control devices consist of the following:
Emissions Control Device[email protected]

Scrubber ID


Scrubber Name



1, 2

Packed Tower Scrubber

Two (2) Duall Packed Tower Carbon Methanol Vapor Scrubbers used to control emissions of methanol by a factor of 99.0% from DCST 1, 2, 3, and 4.


1, 2

Packed Tower Scrubber

Two (2) Duall Packed Tower Alternate Carbon Methanol Vapor Scrubbers used to control emissions of methanol by a factor of 99.0% from ACST 1 and 2 as well as MST 5, 6, and 7 and the 650 gallon day tank.

The proposed emission limits are as follows:

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. 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 Permittee shall ensure that the vented methanol control system and handling procedures, and the closed vent system of the DCST at the facility are consistent with the optimal operation of the methanol scrubbing system so as to achieve a removal efficiency of at least 99.0 percent of methanol vapors from the storage tanks exhaust streams (including both working and breathing losses) so as to achieve a maximum methanol outlet concentration of 980 ppmv. [20 DCMR 201]

The application to operate the ENR system and the draft permit renewal and supporting documents are 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 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 - Air Quality Division

Department of Energy and Environment
1200 First Street NE, 5th Floor
Washington, DC 20002

[email protected]

No comments or hearing requests submitted after January 8, 2018 will be accepted.