VPDES Permit VA0020460|
Vint Hill Farms WWTP
July 17, 2003
Warrenton Community Center
On November 15, 2002, DEQ received a VPDES Permit Application from Fauquier County Water and Sanitation Authority for the reissuance of the permit for Vint Hill Farms Station Waste Water Treatment Plant. The treatment plant is located on the closed Vint Hill Farm Station army base and currently discharges to South Run, a tributary to Lake Manassas, the drinking water source for Manassas, Manassas Park, and parts of Prince William County. The current design flow for this facility is 0.246 mgd. In this reissuance, the Sanitation Authority requested two flow increases to 0.6 mgd and 0.95 mgd.
The current discharge point is less than 5 miles from Lake Manassas and the proposed flow increases will discharge to Kettle Run, which is not a tributary to Lake Manassas. This would result in the new discharge point beginning approximately 37 miles up river from the Fairfax County Water Authority’s intake in the Occoquan Reservoir.
The Vint Hill treatment plant is located in the Occoquan River Watershed near Warrenton, which makes this facility subject to the Occoquan Policy, 9 VAC 25-410. The interpretation and implementation of the Occoquan Policy is the main issue in this reissuance. This facility is subject to two different parts of the Occoquan Policy:
- Part 20 states that there shall be preferably two but no more than three regional sewage treatment plants in the Occoquan Watershed and one of the plants shall be in Fauquier County near Warrenton.
- Part 30 states that existing sewage treatment plants may expand, provided that it is not feasible to connect to a regional plant, and that their loadings not increase.
There is no regulatory definition of the term regional. In this permitting process staff has likened regional to major and made the following interpretation and implementation of the policy:
1. The Vint Hill treatment plant is subject to Part 30 until it becomes a major STP, that is, a design flow of 1.0 mgd or greater. At that time the treatment plant will be subject to the requirements for a regional plant under Part 20.
2. The above implementation is premised on Vint Hill treatment plant eventually
becoming the regional plant specified by Part 20. That is, DEQ will recommend
to the SWCB denial of any application for another STP becoming the regional
plant in the Warrenton area.
Staff recognizes that the above is an interpretation and that there is no definitive right answer. We believe this interpretation achieves a balanced compromise with regard to regulatory parity, allows for future sewage planning, and most important, does not compromise existing water quality and provides opportunity for improved water quality.
Notice of the proposed permit reissuance and public hearing information were published in the Fauquier Citizen newspaper on June 12 and June 19, 2003.
DEQ has received written comments from Fairfax County, City of Manassas, City of Manassas Park, Upper Occoquan Sewage Authority (UOSA), Fairfax County Water Authority, Prince William County Service Authority, and State Senator Charles Colgan. These comments were submitted before the public comment period and staff has entered them into the record. All of the aforementioned commenters have objected to the above interpretation.
The following is a summary of the six comments staff have received to date and with staff’s responses.
Declaration of Regional Plant - The Fauquier County Water and Sanitation Authority stated that staff should not predetermine the Vint Hill treatment plant as the regional plant through this permitting process and that it should be sufficient for DEQ to note that the expansion is in full compliance with Part 30 of the Policy.
Staff Response: It is DEQ’s job to interpret and implement regulations and provide explanation there of. The destiny of this plant as the regional plant is part of the interpretation. Such a declaration is necessary to notify the permittee and everyone that the interpretation of regional meaning major is in part based on the presumption that there will be no other STPs in this area. We do not believe it would be acceptable to allow the Vint Hill treatment plant to expand to 0.95 mgd and allow another plant to be constructed and discharge under Part 20 of the policy.
Regulatory Equity - Most of the commenters stated that it would be neither prudent nor equitable to allow a neighboring jurisdiction within the Occoquan Watershed to digress from the intent of the Occoquan Policy, which mandates stringent wastewater treatment standards and consistently high reliable performance; that upon any expansion, the Vint Hill treatment plant should be declared a regional plant and be required to meet the criteria of Part 20 of the policy.
Staff Response: Staff believes the draft permit is consistent with the Occoquan
Policy; part 30 which allows expansions of existing plants. Further, staff believes
the no net increase in effluent loadings in the draft permit is in keeping with
the Policy. The following are the effluent limits for the 0.95 design flow in
the draft permit:
Feasibility to connect to a regional plant – The Occoquan Policy requires that before a plant in the Occoquan watershed may be expanded, the applicant must show that it is not feasible for the flow to be directed to a regional plant and that the quantities of pollutant loadings discharged from the expanded plant must not increase loads to the receiving streams and that no such determination has been made.
Staff Response: In 1997, FCWSA conducted an evaluation of five wastewater handling alternatives for the Vint Hill area. The alternatives included connection to UOSA and expansion of the Vint Hill treatment plant. The final recommendation, based largely on costs, was expansion of the Vint Hill treatment plant. The estimated 20-year Capital and Operation costs for the connection to UOSA were $39.27M. The 20-year Capital and Operation costs for the expansion of the Vint Hill treatment plant were $32.4M. Further, Fauquier believes the expansion option provides them greater flexibility since they would not be subject to agreements with other jurisdictions.
Staff did not require any further analysis of feasibility for the following reasons:
1. The only existing regional plant is UOSA and Fauquier County is not a member jurisdiction to UOSA.
2. The Occoquan Policy recognizes the need for a plant in the Warrenton area and the Fauquier Water and Sanitation Authority has determined expansion is most feasible for them.
3. Staff's acceptance of general information for a feasibility analysis is consistent with the precedent set in a previous expansion request. In 1990, Prince William County Service Authority requested permission to expand the Nokesville STP, another pre-existing STP in the watershed. Staff accepted the Authority's determination that expanding the plant was the most feasible and the preferred approach to dealing with flows in that area of the watershed without any detailed analysis.
One-time Improvement of an existing Wastewater facility – The Fairfax County Water Authority interprets Part 30 of the Occoquan Policy to relate to a single one-time improvement of an existing waste treatment facility and not for the replacement of said facility which the FCWSA is proposing to do.
Staff Response: The Occoquan Policy does not state that there shall only be
one expansion. Further, it is common practice for permittees to request permits
for the maximum flow needed to address long range plans. Staff considers the
maximum flow requested as the expansion request and any smaller flows as intermediate
flows. Staff believes the two expanded flow tiers are allowable under the Policy.
Upstream drinking water supply (Lake Manassas) - The City of Manassas expressed concerns with the discharge and its proximity to the down stream drinking water supply in Lake Manassas.
Staff Response: These comments were received before Sanitation Authority modified their application for the discharges to go to Kettle Run. Kettle Run is not in the Lake Manassas watershed and the expanded flows will have no impact on Lake Manassas.
New Loadings to Kettle Run - Fairfax County commented that the proposed discharge to Kettle Run violates the Occoquan Policy, unless the plant is required to meet the regional plant criteria, because these pollutant loadings would be new to Kettle Run.
Staff Response: The Occoquan Policy does not prohibit new loadings to streams within the watershed; part 20.G allows new discharges to be permitted. With specific regard to STPs, staff believes the intent of the Policy is to protect drinking water intakes from STP discharges. By moving the discharge to Kettle Run, the discharge is no longer above Lake Manassas thereby providing maximum protection for that drinking water source. And, since the loadings are not increasing, there is no net effect on the Occoquan Reservoir and Fairfax County Water Authority's intake.This concludes the staff presentation.