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Virginia Regulatory Town Hall
Department of Environmental Quality
State Water Control Board

General Notice
Revised (Regulatory Text Added) General Notice - Public Comment Opportunity - Proposed Ammonia Criteria Phased Implementation Program
Date Posted: 7/18/2018
Expiration Date: 10/5/2018
Submitted to Registrar for publication: YES
No comment forum defined for this notice.

Title of Regulation: 9VAC25-260 Water Quality Standards (amending 9VAC25-260-155)

Statutory Authority: § 62.1-44.15 of the Code of Virginia; Clean Water Act (33 USC § 1251 et seq.); 40 CFR Part 131.

Public Hearing Information:

September 11, 2018 – 2:00 p.m.  - Department of Environmental Quality, Blue Ridge Regional Office, 3019 Peters Creek Road, Roanoke, VA 24019

September 13, 2018 – 2:00 p.m. - Department of Environmental Quality, Piedmont Regional Office, 4949-A Cox Road, Glen Allen, VA 23060

Public Comment Period: August 6, 2018 through October 5, 2018

Substance:  Ammonia Criteria - 9VAC25-260-155. The purpose of this notice is to solicit comment regarding additional proposed language developed to address the directives of House Bill 1475, passed by the 2018 General Assembly. Language has been developed for the proposal to amend section 9VAC25-260-155. The amendment includes new nationally recommended aquatic life criteria, issued by EPA in 2013, for ammonia in freshwater. Like the current criteria, the proposed criteria are calculated as a function of temperature and pH and account for the presence or absence of trout and early life stages of fish. The recalculated ammonia criteria now incorporate toxicity data for freshwater mussels in the family Unionidae, which are the most sensitive organisms in the recalculation data base. The new criteria are about twice as stringent as the existing criteria primarily because more recent toxicity data show that mussels and snails (including endangered species) are very sensitive to ammonia and the current ammonia criteria do not provide sufficient protection for these species. Site specific options to calculate criteria omitting mussel toxicity data are proposed to be used in waters where a demonstration has been made that mussels are absent; however, consultation with U.S. Fish and Wildlife Service and the Virginia Department of Game and Inland Fisheries indicate freshwater mussels should be considered ubiquitous in Virginia and likely to be present in any perennial waterbody.

This is a continuation of a proposal to amend the water quality standards which was the subject of a Notice Of Public Comment (NOPC) published in the Virginia Register of Regulations on September 18, 2017 (Volume 34, Issue 2). The NOPC proposes several amendments to the water quality standards but the agency decided to delay the adoption of the amendments for freshwater ammonia criteria (9VAC25-260-155. A-C) due to the passage of House Bill 1475 during the 2018 General Assembly. The legislation directs the State Water Control Board (the Board) not to adopt the most recent ammonia criteria recommended by EPA unless the Board includes in such adoption a phased implementation program consistent with the federal Clean Water Act with certain funding and timing considerations. 

Full text of the regulatory language is below and will be available on the Department of Environmental Quality's website at on August 6, 2018.

9VAC25-260-155. Ammonia surface water quality criteria.

A. Preamble Narrative


B. Freshwater Acute Criteria – Trout absent or present


C. Freshwater Chronic Criteria – Mussels and early life stages of fish present


D. Site Specific Freshwater Criteria Considerations – Mussels and/or early life stages of fish absent


E. Saltwater Criteria - acute


F. Saltwater Criteria - chronic


G. [Implementation of ammonia criteria through Virginia Pollutant Discharge Elimination System (VPDES) Permits. The ammonia criteria in subsections A, B, and C of this section shall be addressed during individual VPDES permit reissuance for existing dischargers subject to new or more restrictive water quality-based ammonia effluent limits in accordance with the department's standard permitting practices except as follows:

1. Notwithstanding any other regulatory requirement, a compliance schedule may be established that exceeds the term of the permit, subject to a demonstration by the permittee that a longer period is necessary to allow a reasonable opportunity to attain compliance with the new or more restrictive ammonia discharge requirements. The department's consideration for such a demonstration shall be made on a case-by-case basis and shall require compliance as soon as possible, but not later than the applicable statutory deadline under the Clean Water Act.

2. Information to be provided under subdivision 1 of this subsection may include such factors as (i) opportunities to minimize costs to the public or facility owners by phasing in the implementation of multiple projects, (ii) time needed for freshwater mussel habitat determinations, and (iii) other relevant factors.

3. If a permit establishes a schedule of compliance that exceeds the term of the permit, the compliance schedule shall set forth interim requirements and the dates for their achievement.

a. The time between interim dates shall not exceed one year.

b. If the time necessary for completion of any interim requirement is more than one year and is not readily divisible into stages for completion, the permit shall specify interim dates for the submission of reports of progress toward completion of the interim requirements and indicate a projected completion date.

c. The permit shall be written to require that no later than 14 days following each interim date and the final date of compliance, the permittee shall notify the department in writing of its compliance or noncompliance with the interim or final requirements, or submit progress reports if subdivision 3 b of this subsection is applicable.

d. Any change to an interim compliance date in the schedule of compliance will be deemed to be a minor modification of the permit, provided the new date is not more than 120 days after the date specified in the existing permit and does not interfere with attainment of the final compliance date requirement. ]


[Implementation of Freshwater Ammonia Criteria in subsections B and C through VPDES Permits issued pursuant to 9VAC25-31 - Virginia Pollutant Discharge Elimination System (VPDES) Permit Regulation. 


  1. The above criteria in subsections B and C shall be implemented in VPDES permits that are being reissued in accordance with the following schedule:


  1. Major municipal and industrial facilities – 6 months following the WQS effective date

  2. Minor municipal facilities with design flows greater than or equal to 100,000 gallons per day and less than 1 million gallons per day and all minor industrial facilities – 18 months following the WQS effective date.

  3. Minor municipal facilities with design flows that are less than 100,000 gallons per day – 30 months following the WQS effective date.


  1. VPDES permits shall not be revoked and reissued to avoid or delay being subject to the freshwater ammonia criteria in subsections B and C in accordance with the above schedule.


  1. The provisions of 9 VAC 25-31-250.A.3 notwithstanding, a permittee may request and the board may authorize, as appropriate, an extended schedule of compliance, which exceeds the term of the VPDES permit and may include multiple permit cycles to achieve effluent limits based on the freshwater ammonia water quality criteria in subsections B and C.


  1. Any extended schedule of compliance necessary for the implementation of the freshwater ammonia criteria shall require compliance as soon as possible in accordance with 9 VAC 25-31-250.A.1.The board may consider the following factors on a case-by-case basis, relying on information provided by the permittee, in making a determination of “as soon as possible”:


    1. The relative priority of ammonia criteria and other water quality and water infrastructure needs of the local community,

    2. Availability of grant funding pursuant to VA Code § 10.1-2131 and other treatment facility expansion and upgrade plans,

    3. Whether an extended schedule of compliance is appropriate for facilities or classes of facilities, and

    4. Appropriate mechanisms to address affordability limitations and financial hardship situations remaining notwithstanding parts i through iii above.


  2. Any request by the permittee for an extended schedule of compliance shall include at the time of permit application the following information at a minimum:

    1. Documentation of other water quality and water infrastructure projects that are in the planning, design or construction process and the relative priority of the projects in relation to compliance with the ammonia criteria.

    2. A preliminary engineering analysis of treatment facility upgrade alternatives necessary to meet the freshwater ammonia criteria. The analysis may include any additional upgrade or expansion plans currently under consideration.The analysis shall be prepared by a professional engineer registered in Virginia and shall include an estimation of the capital and operations and maintenance costs.

    3. An assessment of project affordability including an evaluation of the required sewer use fees versus median household income and identification of all potential sources of funding for enhanced ammonia treatment.

    4. Documentation that demonstrates theminimum estimated time required and schedule to design, fund and construct the selected treatment alternative.

    5. An evaluation, prepared by a professional engineer registered in Virginia, of the highest achievable condition (HAC) regarding nitrification capabilities of the existing treatment facility under the influent loading conditions expected during the term of the VPDES permit as well as under design loading conditions.


  3. Any VPDES permit that authorizes an extended schedule of compliance for meeting the freshwater ammonia criteria that exceeds the permit term shall include interim effluent limitations based on the HAC attainable during the term of the permit, final effluent limitations and a final compliance date.


  4. New dischargers defined in 9VAC25-31 are not eligible for extended schedules of compliance under this section; however, they remain eligible for schedules of compliance consistent with 9VAC25-31-250.


  1. A permittee may seek a site-specific modification or variance to the freshwater ammonia water quality criteria under 9VAC25-260-140.D, or 9VAC25-260-140.E as applicable.]




Contact Information
Name / Title: David Whitehurst 
Address: 1111 East Main Street, Suite 1400
P.O. Box 1105
Richmond, 23218
Email Address:
Telephone: (804)698-4121    FAX: (804)698-4032    TDD: ()-