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HomeMy WebLinkAboutNC0044423_Other Correspondence_20211025 If Dewberry Dewberry Engineers Inc. 704.509.9918 9300 Harris Corners Parkway 704.509.9937 fax Suite 220 www.dewberry.com Charlotte, NC 28269 January 17,2018 Revised January 22,2018(Revs) Revised January 29,2018(Rev2) Revised March 5,2018(Rev3) RECEIVED Mr.Jeff Pierce Physical Plant Acting Director .)I.,T 2 5 2021 Appalachian State University Planning,Design and Construction NCDEQIDWRINPDES DD Dougherty Administration Building Boone,NC 28608 Reference: Appalachian State University Water Treatment Plant Permit Evaluation Dear Mr.Pierce: Dewberry Engineers Inc. (Dewberry) is pleased to submit this proposal to assist the Appalachian State University (ASU) Water Treatment Plant (WTP) evaluate alternatives to modify the facility's National Pollutant Discharge Elimination System(NPDES)permit.This proposal is based upon our December 20, 2017 conversation. To facilitate your review,our proposal presents the Project Understanding,Scope of Service,and Fee. PROJECT UNDERSTANDING Dewberry understands the ASU WTP discharges filter backwash to Norris Branch Reservoir,also known as Appalachian State Reservoir, under the auspices of NPDES NCoo44423.The most recent permit became effective April 1, 2017.Norris Branch Reservoir is classified as a Water Supply II,Trout,and High Quality Water and as a result is subject to stringent water quality standards.The current NPDES permit subjects the ASU WTP to an effluent turbidity limit of io NTU (nephelometric turbidity unit) and a minimum effluent dissolved oxygen of 6 mg/l. ASU WTP is currently not able to consistently meet the effluent dissolved oxygen limit or the effluent turbidity limit.The NPDES permit imposes a schedule which requires compliance with the effluent turbidity limit by July 1,2019. These effluent limits are identical to the surface water quality in-stream standards for trout waters (15A NCAC.o2B.o211). In-stream water quality standards are established as criteria to achieve within the water body.Typically,in-stream water quality standards are not applied directly as effluent NPDES permit limits, except in instances where the receiving stream is a zero flow stream.In addition,when in-stream standards are used to develop numerical effluent limits,a dilution factor is typically applied which takes into account the critical low flow rate of the receiving water body.The critical low flow rates are established by the United States Geological Survey(USGS). Moreover, it is customary for NPDES permits to contain upstream and downstream monitoring requirements to confirm in-stream water quality standards are maintained. The ASU WTP does not discharge into a zero flow stream. However,in developing the ASU WTP effluent limits, no dilution credit was given for the receiving stream because it is a lake/reservoir. DEQ set the effluent limits equal to the in-stream standards. The responsibility to establish a dilution ratio for Norris Branch Reservoir was placed on ASU as the permittee. The ASU WTP NPDES permit includes upstream Mr.Jeff Pierce Project:ASU Water Treatment Plant Permit Evaluation January 17,2018 Revised March 5,2018(Rev3) Page 2 of 6 monitoring for turbidity and dissolved oxygen but does not include downstream monitoring for these parameters. Dewberry understands ASU is interested in evaluating regulatory solutions for achieving compliance with the effluent turbidity and dissolved oxygen limits.In Dewberry's opinion,multiple options are available for modifying the NPDES permit which would be consistent with the intent of water quality regulations,would improve the potential for ASU to maintain compliance with the NPDES permit,and be protective of water quality. Based on discussion on January 22,2018,Dewberry understands ASU is interested in relocating the DO sampling location and add a fresh-air intake sleeve (aeration device). These changes are targeted to increasing the DO concentration in the effluent samples. Per correspondence from Mr.George Smith,the aeration device will require modification of the existing permit,but the revised sampling location will not. The extent of infrastructure permit modification will be placed on the DEQ meeting agenda. Dewberry will present the proposed infrastructure permit modifications at the meeting with DEQ. rr Based on discussion on January 29, 2018, Dewberry understands ASU would like the current scope to include completion of the permit modification application based on the assumption that Option.'is agreed upon with DEQ as the appropriate path forward. The scope below has been revised to include the previously Future Task 4. SCOPE OF SERVICE Task i-Information and Regulatory Review(Work Previously Completed) Dewberry has previously completed the following activities in preparation for assisting ASU WTP with this permit evaluation. • Participate in conference calls with ASU • Review ASU WTP NPDES permit fact sheet,current NPDES permit,and historical NPDES permits • Review ASU WTP effluent data • Review water quality regulations • Review receiving water stream classification and impairment status • Assist ASU with writing the response to Notice of Violation & Intent to Assess Civil Penalty (Tracking Number:NOV-2o18-LV-oo34)fir September i3,2017. Task 2—Kickoff Meeting and WTP Site Visit As an initial activity,two Dewberry engineers will participate in a site visit and project kickoff meeting at the ASU WTP. The project kickoff meeting will include representatives from Dewberry and ASU but will not include DEQ.The objective of this meeting will be to review information previously provided by ASU and request additional information if needed,develop the project plan,tour the WTP,observe the discharge outfall and sampling locations, discuss project schedule, and establish lines of communication with the University and DEQ. The proposed infrastructure modifications will be reviewed. During the meeting, Dewberry will present the path forward options, presented in more detail in Task 3 scope below, and will discuss the advantages/disadvantages of each option with ASU. Dewberry. Mr.Jeff Pierce Project:ASU Water Treatment Plant Permit Evaluation January 17,2018 Revised March 5,2018(Rev3) Page 3 of 6 Dewberry will draft meeting minutes to document the kick off meeting.Dewberry will submit a draft of the meeting minutes to ASU for review and comment. Dewberry will incorporate mutually agreed upon revisions prior to a final submittal. Task 3—Meeting with DEQ Dewberry will coordinate a meeting with the NC DEQ Winston-Salem Regional Office NPDES permitting personnel. Due to potential schedule constraints with DEQ personnel, Dewberry suggests setting this meeting date as an initial project activity to ensure this meeting does not become a schedule limiting activity.Dewberry will contact the Winston-Salem Regional Office to schedule the meeting. The objective of the meeting will be to propose permit modification strategies to DEQ. Dewberry will use information previously reviewed in Task i and Task 2 to develop a presentation for the meeting. The presentation will serve as the meeting agenda and Dewberry will review the presentation with ASU prior to the meeting.We assumed two Dewberry engineers will attend the meeting with ASU representatives and the meeting will take place at the Winston-Salem Regional Office after completion of Task 2. Dewberry anticipates proposing two potential permitting strategies at the meeting. The first proposed strategy"Option 1"will be to modify the permit to monitor turbidity and dissolved oxygen upstream and downstream of the discharge and remove the numerical effluent limits. If the downstream sampling indicates the in-stream standards are met,an effluent limit is deemed unnecessary to comply with water quality regulations;therefore,we would request to remove the numerical effluent limit.The intent of adding the upstream sampling is to confirm that the receiving water body is not exceeding the in-stream water quality standard before the ASU WTP discharge.This first strategy"Option 1"is the preferred path forward. Dewberry considers this consistent with the intent of the water quality regulations. If the first proposed strategy is not accepted by DEQ,a second potential path forward"Option 2"would be to perform a study to establish the dilution factor provided by Norris Branch Reservoir.DEQ may require ASU to establish the dilution factor in order to modify the ASU NPDES permit. A mixing zone study is currently listed in Special Condition A(3) of the ASU WTP NPDES permit as an acceptable study for inclusion in the required Corrective Action Plan(CAP). It is anticipated that DEQ would accept a mixing zone study as a path forward;however,this is not deemed the preferred alternative because it will require significantly more effort compared to the first proposed strategy("Option i").It should also be noted that if a dilution factor is established and used to increase the effluent turbidity limit,it does not guarantee the increased limit will be high enough to resolve the potential compliance concerns.It is also worth noting that a dilution factor could be used to increase other effluent limits within the NPDES permit,specifically copper and zinc. Concurrently with "Option 1", Dewberry anticipates proposing permit modifications for infrastructure changes. These changes include relocating the DO sampling location and add a fresh-air intake sleeve (aeration device). These changes are targeted to increasing the DO concentration in the effluent samples. The goal of the meeting with DEQ is to select a path forward that is acceptable to ASU and DEQ.Dewberry will draft meeting minutes to document the discussion.After ASU reviews the draft meeting minutes and provides comments,if necessary,Dewberry will update and distribute the meeting minutes to all attendees. Dewberry' • Mr.Jeff Pierce Project:ASU Water Treatment Plant Permit Evaluation January 17,2018 Revised March 5,2018(Rev3) Page 4 of 6 Task 4—Permit Modification Application The preferred permitting strategy, identified as "Option 1", is to modify the ASU WTP NPDES permit to include upstream and downstream in-stream monitoring for turbidity and dissolved oxygen and eliminate the numerical effluent limits for those parameters.If DEQ finds this strategy acceptable, the next step would be to submit an application to modify the NPDES permit. Modifying the sampling locations and effluent limits is deemed a major permit modification.A major permit modification may require submittal of complete application forms and appropriate supplemental documentation. Dewberry will complete the DEQ Form C-WTP and develop a cover letter for the permit modification. Dewberry assumes no other supplemental documentation or sampling is required by DEQ to support the permit modification.Dewberry will submit a draft of the permit application and cover letter to ASU to review and comment.Dewberry will host a teleconference to review the draft application with ASU and will make mutually agreed upon revisions.Dewberry assumes ASU will be responsible for submitting the application and any application fees. If DEQ is amenable to the proposed infrastructure improvements strategy, a permit modification with supporting documentation and an Authorization to Construct will be required. The scope and fee to support ASU with the Authorization to Construct and plant modification construction documents for infrastructure improvements are not included in this proposal. Therefore, if this is the selected path forward,Dewberry can submit a separate fee proposal detailing the required scope. Future Task 5—Water Quality Modeling and Permit Modification If"Option i" cannot be agreed to by DEQ, ASU may be required to establish a dilution ratio for Norris Branch Reservoir "Option 2" before allowing modification of effluent permit limits. For discharges into streams or rivers,numerical effluent NPDES limits are often established by allowing credit for the dilution of the discharge into the receiving water body.The dilution credit is most often calculated at the receiving water's low flow condition,or 7Q1o.The 7Qio is defined as the minimum average flow for a period of seven consecutive days that has an average recurrence of once in ten years. This permitting strategy does not appear to have been applied by DEQ to Norris Branch Reservoir which is permitted as a lake discharge. Hydraulic modeling of Norris Branch Reservoir could be performed to quantify the dilution provided by the reservoir.The Reasonable Potential Analysis performed by DEQ to establish the effluent permit limits could be reevaluated to apply the dilution ratio determined by the study which would result in higher effluent permit limits. Once the hydraulic modeling is performed, a permit modification application can be completed as described in Future Task 3.It is not guaranteed that the higher effluent limits would resolve the compliance concerns. The scope and fee to support ASU with water quality modeling and permit modification is not included in this proposal.Therefore,if this is the selected path forward,Dewberry can submit a separate fee proposal detailing the required scope. FEES We propose to perform Tasks 1, 2, 3, and 4 as described in the Scope of Services for a lump sum fee of $19,5oo.After Task 3 is complete,if Option 2 is selected and Future Task 5 is required,a fee estimate for future work can be provided. 144 Dewberry' Mr.Jeff Pierce Project:ASU Water Treatment Plant Permit Evaluation January 17,2018 Revised March 5,2018(Rev3) Page 5 of 6 The following assumptions were made in preparing this fee estimate: • Dewberry has allocated for one meeting at the ASU WTP and one meeting with DEQ at the Winston- Salem Regional Office. • Dewberry has not included allocation for sample collection or analysis if additional sampling is required. • Dewberry excludes writing responses for additional Notice Of Violations beyond the one included in the Task 1 Scope of Work. • Dewberry excludes preparing an Authorization to Construct and design documentation if installation of additional equipment is required. • Dewberry assumes ASU is responsible for permit application fees. SCHEDULE A preliminary project schedule is presented below. Please note that this schedule is subject to DEQ availability and responsiveness. • Kickoff Meeting at ASU WTP—Within 3 weeks of receiving Notice to Proceed • Submit Draft Agenda for DEQ Meeting to ASU—2 weeks after Kickoff Meeting • Meeting with DEQ—Within 4 weeks of Kickoff Meeting(subject to DEQ availability) • Submit Draft Meeting Minutes to ASU—1 week after DEQ Meeting • Submit Draft Form C-WTP and Cover Letter to ASU—3 weeks after DEQ Meeting ADDITIONAL SERVICES This proposal is based upon our current understanding of local, state and federal requirements and regulations and our understanding of the project as described herein. Any modifications to these requirements and regulations, or other requirements not provided for herein, which require additional services will be discussed with Appalachian State University and an additional services proposal will be generated by Dewberry. AUTHORIZATION If you have any questions, please do not hesitate to contact us. We look forward to serving Appalachian State University on this project. If you find our proposal acceptable, please execute a purchase order to allow us to begin work. Sincerely, Dewberry Engineers Inc. 17.71:1,4 Anthony"Tony"Miller,P.E. Project Manager cc: Leigh-Ann Dudley,PE,Dewberry Katie Jones,PE,Dewberry ee Dewberry- Mr.Jeff Pierce Project:ASU Water Treatment Plant Permit Evaluation January 17,2018 Revised March 5,2018(Rev3) Page 6 of 6 The foregoing proposal of Dewberry Engineers Inc.is accepted: Print(Type)Individual,Firm,or Corporate Name Signature of Authorized Representative Date Print(Type)Name of Authorized Representative and Title • Dewberry.