Any owner whose registration statement is accepted by the board will receive the following general permit and shall comply with the requirements of the general permit.
General Permit No.: VAN000000
Effective Date: January 1, 2022
Expiration Date: December 31, 2026
GENERAL PERMIT FOR TOTAL NITROGEN AND TOTAL PHOSPHORUS DISCHARGES AND NUTRIENT TRADING IN THE CHESAPEAKE WATERSHED IN VIRGINIA
AUTHORIZATION TO DISCHARGE UNDER THE VIRGINIA POLLUTANT DISCHARGE ELIMINATION SYSTEM AND THE VIRGINIA STATE WATER CONTROL LAW
In compliance with the provisions of the Clean Water Act, as amended, and pursuant to the State Water Control Law and regulations adopted pursuant to it, owners of facilities holding a VPDES individual permit or owners of facilities that otherwise meet the definition of an existing facility, with total nitrogen or total phosphorus discharges, or both to the Chesapeake Bay or its tributaries, are authorized to discharge to surface waters and exchange credits for total nitrogen or total phosphorus, or both.
The authorized discharge shall be in accordance with the registration statement filed with DEQ, this cover page, Part I-Special Conditions Applicable to All Facilities, Part II-Special Conditions Applicable to New and Expanded Facilities, and Part III-Conditions Applicable to All VPDES Permits, as set forth herein.
Nitrogen Load (lbs/ year) = flow (MGD) x 8.0 mg/l x 8.345 x 365 days/year
Phosphorus Load (lbs/ year) = flow (MGD) x 1.0 mg/l x 8.345 x 365 days/year
Flows used in the preceding formulae shall be the design flow of the treatment works from which the affected facility currently discharges.
The regional facility shall be eligible to generate credits.
Parameter | Sample Type and Collection Frequency | ||||
STP design flow | [GREATER THAN EQUALS TOO]20.0 MGD | 1.0 - 19.999 MGD | 0.5 - 0.999 MGD | 0.040 - 0.499 MGD | < 0.040 MGD |
Effluent TN load limit for industrial facilities | [GREATER THAN EQUALS TOO]100,000 lb/yr | 50,000 - 99,999 lb/yr | 487 - 49,999 lb/yr | < 487 lb/yr | |
Effluent TP load limit for industrial facilities | [GREATER THAN EQUALS TOO]10,000 lb/yr | 5,000 - 9,999 lb/yr | 37 - 4,999 lb/yr | < 37 lb/yr | |
Flow | Totalizing, Indicating, and Recording | 1/Day, see individual VPDES permit for sample type | |||
Nitrogen Compounds (Total Nitrogen = TKN + NO2- (as N) + NO3- (as N)) | 24 HC 3 Days/Week | 24 HC 2 Days/Week* | 8 HC 2 Days/Week* | 8 HC 2/Month, > 7 days apart | 1/Month Grab |
Total Phosphorus | 24 HC 3 Days/Week | 24 HC 2 Days/Week* | 8 HC 2 Days/Week* | 8 HC 2/Month, > 7 days apart | 1/Month Grab |
*Two flow composited samples taken in the same calendar week that are then composited by flow into a single weekly composite sample for analysis shall be considered to be in compliance with this requirement. |
where:
ML = total monthly load (lb/mo) = average daily load for the calendar month multiplied by the number of days of the calendar month on which a discharge occurred
DL = daily load = daily concentration (expressed as mg/l to the nearest 0.01 mg/l) multiplied by the flow volume of effluent discharged during the 24-hour period (expressed as MGD to at least the nearest 0.01 MGD and in no case less than two significant digits), multiplied by 8.345. Daily loads greater than or equal to 10 pounds may be rounded to the nearest whole number to convert to pounds per day (lbs/day). Daily loads less than or equal to 10 pounds may be rounded to no fewer than two significant figures.
s = number of days in the calendar month in which a sample was collected and analyzed
d = number of discharge days in the calendar month
For total phosphorus, all daily concentration data below the quantification level (QL) for the analytical method used shall be treated as half the QL. All daily concentration data equal to or above the QL for the analytical method used shall be treated as it is reported. If all data are below the QL, then the average shall be reported as half the QL.
For total nitrogen (TN), if none of the daily concentration data for the respective species (i.e., TKN, nitrates/nitrites) are equal to or above the QL for the respective analytical methods used, the daily TN concentration value reported shall equal one half of the largest QL used for the respective species. If one of the data is equal to or above the QL, the daily TN concentration value shall be treated as that data point as reported. If more than one of the data is above the QL, the daily TN concentration value shall equal the sum of the data points as reported.
The quantification levels shall be less than or equal to the following concentrations:
Parameter | Quantification Level |
TKN | 0.50 mg/l |
Nitrite | 0.10 mg/l |
Nitrate | 0.20 mg/l |
Nitrite + Nitrate | 0.20 mg/l |
Higher QLs may be approved on a case-by-case basis where a higher QL routinely results in reportable results of the species in question or is otherwise technically appropriate based on standard lab practices.
The total year-to-date mass load shall be calculated in accordance with the following formula:
where:
AL-YTD = calendar year-to-date annual load (lb/yr)
ML = total monthly load (lb/mo)
The total annual mass load shall be calculated in accordance with the following formula:
where:
AL = calendar year annual load (lb/yr)
ML = total monthly load (lb/mo)
Discharges reportable to the department under the immediate reporting requirements of other regulations are exempted from this requirement.
The board may waive the written report on a case-by-case basis for reports of noncompliance under Part III I if the oral report has been received within 24 hours and no adverse impact on state waters has been reported.
NOTE: The immediate (within 24 hours) reports required in Part III G, H, and I may be made to the department's regional office. Reports may be made by telephone or online at https://www.deq.virginia.gov/our-programs/pollution-response. For reports outside normal working hours, a message may be left and this shall fulfill the immediate reporting requirement. For emergencies, the Virginia Department of Emergency Management maintains a 24-hour telephone service at 1-800-468-8892.
"I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations."
The permittee shall comply with effluent standards or prohibitions established under § 307(a) of the Clean Water Act for toxic pollutants and with standards for sewage sludge use or disposal established under § 405(d) of the Clean Water Act within the time provided in the regulations that establish these standards or prohibitions or standards for sewage sludge use or disposal, even if this permit has not yet been modified to incorporate the requirement.
For purposes of this section, the time for inspection shall be deemed reasonable during regular business hours or whenever the facility is discharging. Nothing contained herein shall make an inspection unreasonable during an emergency.
9 Va. Admin. Code § 25-820-70
Statutory Authority: § 62.1-44.15 of the Code of Virginia; 33 USC § 1313(e) of the Clean Water Act.