Amend the Water Quality Management Planning Regulation (9 VAC 25-720-70.C, Rappahannock River Basin), to increase total nitrogen (TN) and total phosphorus (TP) waste load allocations (WLAs) for the Town of Culpeper wastewater plant (VPDES Permit No. 0061590). Current nutrient WLAs are TN = 54,820 lb/yr; TP = 4,112 lb/yr, based on a design flow of 4.5 million gallons per day (MGD). The Town is expanding the plant to 6 MGD and installing state-of-the-art nutrient reduction technology. Construction is underway, with work expected to be completed and the facility certified for operation by 12/31/10. Culpeper requests the WLAs be amended to TN = 73,058 lbs/yr (an 18,238 lb/yr increase) and TP = 5,479 lbs/yr (a 1,367 lb/yr increase), to reflect the 6 MGD design flow.

Public-notice receipt of the petition and provide for a 21-day public comment period. Upon close of the public comment period, review any comments received and then make a decision to either initiate a rulemaking or place the petition on the Board's next meeting agenda for their consideration.

Take no action

The petition was denied since the Town's request for the increased WLAs due to a plant expansion to 6.0 MGD under the original rulemaking in 2005 was not recommended by the staff, and the Board adopted conditional WLAs for the Town based on a design flow of 4.5 MGD. The Town has the capability to meet its TN WLA by operating the upgraded nutrient reduction technology, now being installed, at its design intent up to a flow of 6.0 MGD. The TP WLA can be achieved at 6.0 MGD design flow through operation at 0.22 mg/l annual average, which is possible using available technology. Given Culpeper County's 1.5 MGD design flow WLAs, at a minimum, for Mountain Run STP and their stated intention to build a 2.5 MGD plant (P&S approved, Certificate to Construct issued but project not yet bid), granting an additional 1.5 MGD capacity and associated WLA to the Town may be excessive for the area and the Rappahannock basin. Further, there appears to be an opportunity for a shared, regional approach to address the capacity needs of the Town and the County for future service areas that has not been fully explored. A Memorandum of Understanding has been signed and discussions have taken place between the localities on this and other issues facing the region, but no final solution has been agreed upon yet. Conditions are essentially the same as when the Board adopted the original "footnoted" WLAs for the Town based on 4.5 MGD, in terms of justifying additional design flow.