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HomeMy WebLinkAboutNC0090140_Draft Fact Sheet_20230525Renewal Fact Sheet - DRAFT 25May2023 NPDES Permit NC0090140 Page 1 DEQ / DWR / NPDES FACT SHEET – NEW NPDES PERMIT NPDES Permit NC0090140 Joe R. Corporon, P. G., Compliance & Expedited Permitting Unit 25May2023 Project Summary / Property Development South End Charlotte Owner, LLC (herein South End or the Permittee) plans to redevelop facility properties (Brownfields Project Number 25073-21-060) by constructing a retail and residential building on land currently occupying addresses 1919, 1923, and 1933 South Blvd, Charlotte. This NPDES Permit application proposes a direct discharge to surface waters of the state as treated groundwater generated during site redevelopment. The Applicant will install up to four (4) groundwater extraction wells to prevent infiltration into proposed excavations advanced below the groundwater table. Said excavations are intended to install potential footings, elevator shafts, and a subgrade generator room. Said facilities will be aggressively sealed to prevent groundwater infiltration, and therefore will not require long-term dewatering facilities. Table 1 - Facility Information Applicant / Facility Name South End Charlotte Owner, LLC Fulbright Laboratories Brownfields Property Operations: Infrastructure excavation dewatering for habitable building Applicant Address: 3990 Hillsboro Pike, Ste 400, Nashville TN 37215 Site Contacts/ Consultants: Michael McNally, Senior VP, Southern Land (615) 778-2889, [michael.mcnally@southernland.com] 3990 Hillsboro Pike, Suite 400, Nashville, TN 37215 Bo Cappleman, PC, Project Manager, Heart / Hickman [rcappleman@harthickman.com] 2923 South Tryon Street, Charlotte 28203 Scott Drury. PE, [Senor] Project Manager, Heart / Hickman Facility Addresses: 1919, 1923, and 1933 South Boulevard, Charlotte 28203 Permitted Flow (MGD) 0.075 MGD Waste Character: 100% industrial, privately owned, <1.0 MGD Facility Class: PCNC Physical / Chemical County: Mecklenburg Permit Status: NEW Regional Office: MRO Stream Characteristics Receiving Stream: UT to Dairy Branch Stream Classification: C Stream Segment: 11-137-8-1 Drainage basin: Catawba Summer 7Q10 (cfs): 0.0 Subbasin [HUC]: 03-08-34 [030501030102] Winter 7Q10 (cfs): 0.0 Use Supported: Overall IR cat. 3c 30Q2 (cfs): 0.0 303(d) Listed: No Average Flow (cfs): 0.0 State Grid: G15NE IWC (%): 100% (Storm-drain - zero-flow conditions, ~1.5 miles to creek) USGS Quad: Charlotte E, NC Draft Peer Reviewer: Renewal Fact Sheet - DRAFT 25May2023 NPDES Permit NC0090140 Page 2 Engineering Alternatives Analysis (EAA): Considering the local urban environment, South End has evaluated discharge alternatives as: • connection to a municipal publicly owned treatment works (POTW) sewer system; • subsurface disposal (nitrification field, infiltration gallery, injection wells, etc.); and, • Spray irrigation These discharge alternatives are judged either not allowable or not feasible, and therefore a present-value cost analysis was not conducted. The Applicant therefore concludes that a surface water discharge is the only viable discharge option (see Application, pages 10 and 11). Proposed Treatment System Groundwater generated by up to four (4) extraction wells will be treated at the surface using physical filtration/adsorption processes. The groundwater will be pumped to an equalization tank, then through a bag filter, thence via an organoclay (zeolite) filtration unit, and finally through granular activated carbon filtration units prior to direct discharge. Treated effluent will be discharged to a storm sewer catch basin located on facility property. The storm water sewer line discharges into Dairy Branch (stream) located approximately 1,400 ft southeast (see map, Figure 3). Discharge into the storm sewer has been approved by Charlotte-Mecklenburg Storm Water Services. Proposed Treatment System: Sample port located upstream of final filter will allow monitoring and recording of filter-system breakthrough prior to discharge to the environment (See Supplement to Permit Cover Sheet). Treatment logs and internal sampling shall be kept available for DWR inspection. As advised by the Applicant, they have no need for long-term monitoring, there this permit will expire in less than two (2) years on June 30, 2025. Renewal Fact Sheet - DRAFT 25May2023 NPDES Permit NC0090140 Page 3 Proposed system components include: • one (1) each equalization tank (proposed 6,000-gallon to 21,000-gallon) • one (1) each bag filter (Rain For Rent BF100 or equivalent); max flow 100 gpm / 10 micron • one (1) filter for heavy metals [HS-200 liquid phase organoclay (i.e., zeolite)] • one (1) each filter for VOCs [granular activated carbon (GAC)]; 1,900 lbs • one (1) each filter for VOCs [granular activated carbon (GAC)]; 1,000 lbs • one (1) each effluent totalizing flow meter. • appurtenant piping to the outfall Spent GAC will be disposed offsite. Logs of internal samples analyzed to document contaminate breakthrough shall be maintained onsite for DWR inspection. Receiving Stream and Outfall 001: The first-encountered receiving Waters of the State [See site location map], is a UT to Dairy Branch [segment 11-137-8-1]. Outfall 001 discharges to a city storm sewer under zero-flow receiving-stream conditions [7Q10/30Q2 = 0.0 cfs]. Effluent limitations therefore assume an instream waste concentration (IWC) of 100%, i.e., this effluent receives no credit for dilution, consistent with storm-sewer discharges statewide. Permitting Strategies - Rationale for Limits: Considering the Permittee’s application for discharge, DWR has established a list of Contaminants of Concern (COCs) for initial sampling. DWR/EPA requires effluent analyses for metals, VOCs, and Semi-VOCs based on data submitted [see permit Section (A. (1.), Footnote 4, and Permit Condition A. (3.)]. Contaminates detected and believed present require monitoring [see A. (1.) Table 2]. Those with established Surface Water Quality Standards, either NC or EPA, have been assigned permit limits equal to those Standards, whichever may be more stringent. Lastly, we include two broader- scoped, but less frequent tests, as EPA 624.1 and 625.1, anticipating the potential need to report so-far undetected COCs [see Section A. (1.)]. For ease of reporting, DWR provides a COC list as permit Section A. (4.). WET Testing: Whole Effluent Toxicity (WET) testing is included as Acute, Monthly, Monitoring and Report only [TAA6C]. WET testing is required for the duration of the permit. Public Notice - New Discharge: The following newspaper blurb will be submitted for Public Notice: “South End Charlotte Owner, LLC applied for an NPDES Permit [NC0090140] for the Fulbright Laboratories Brownfields Property located at addresses 1919, 1923, and 1933 South Boulevard, Charlotte 28203 to discharge treated dewatering wastewater to a UT to Dairy Branch, Catawba River Basin. Water-quality limited parameters include cis-1,2-Dichloroethene (1-2DCE), Tetrachloroethene (PCE), Trichloroethene (TCE), Vinyl Chloride (VC), Total Chromium, and Total lead. This discharge may affect future wasteload allocations to the receiving stream. The Division will review comments on this draft permit if received with 30 days of this Public Notice.” Renewal Fact Sheet - DRAFT 25May2023 NPDES Permit NC0090140 Page 4 PROPOSED SCHEDULE FOR PERMIT ISSUANCE: Public Notice (estimated): June 14, 2023 Issuance (estimated): July 17, 2023 Effective Date (estimated): September 1, 2023 NPDES DIVISION CONTACT If you have questions regarding any of the above or the attached permit, please contact Joe R. Corporon, P.G., email preferred [joe.corporon@ncdenr.gov]. _________________________________25May2023___________ Joe R. Corporon, P.G. DEQ / DWR / NPDES Permitting NPDES Implementation of Instream Dissolved Metals Standards – Freshwater The NC 2007-2015 Water Quality Standard (WQS) Triennial Review was approved by the NC Environmental Management Commission (EMC) on November 13, 2014. The US EPA subsequently approved the WQS revisions on April 6, 2016, with some exceptions. Therefore, metal limits in draft permits out to public notice after April 6, 2016 must be calculated to protect the new standards - as approved. Table 1 Notes: 1. FW= Freshwater, SW= Saltwater 2. Calculation = Hardness dependent standard 3. Only the aquatic life standards listed above are expressed in dissolved form. Aquatic life standards for Mercury and selenium are still expressed as Total Recoverable Metals due to bioaccumulative concerns (as are all human health standards for all metals). It is still necessary to evaluate total recoverable aquatic life and human health standards listed in 15A NCAC 2B.0200 (e.g., arsenic at 10 µg/l for human health protection; cyanide at 5 µg/L and fluoride at 1.8 mg/L for aquatic life protection). Renewal Fact Sheet - DRAFT 25May2023 NPDES Permit NC0090140 Page 5 Table 2. Dissolved Freshwater Standards for Hardness-Dependent Metals The Water Effects Ratio (WER) is equal to one unless determined otherwise under 15A NCAC 02B .0211 Subparagraph (11)(d) Metal NC Dissolved Standard, µg/l Cadmium, Acute WER*{1.136672-[ln hardness](0.041838)} ∙ e^{0.9151 [ln hardness]- 3.1485} Cadmium, Acute Trout waters WER*{1.136672-[ln hardness](0.041838)} ∙ e^{0.9151[ln hardness]- 3.6236} Cadmium, Chronic WER*{1.101672-[ln hardness](0.041838)} ∙ e^{0.7998[ln hardness]- 4.4451} Chromium III, Acute WER*0.316 ∙ e^{0.8190[ln hardness]+3.7256} Chromium III, Chronic WER*0.860 ∙ e^{0.8190[ln hardness]+0.6848} Copper, Acute WER*0.960 ∙ e^{0.9422[ln hardness]-1.700} Copper, Chronic WER*0.960 ∙ e^{0.8545[ln hardness]-1.702} Lead, Acute WER*{1.46203-[ln hardness](0.145712)} ∙ e^{1.273[ln hardness]- 1.460} Lead, Chronic WER*{1.46203-[ln hardness](0.145712)} ∙ e^{1.273[ln hardness]- 4.705} Nickel, Acute WER*0.998 ∙ e^{0.8460[ln hardness]+2.255} Nickel, Chronic WER*0.997 ∙ e^{0.8460[ln hardness]+0.0584} Silver, Acute WER*0.85 ∙ e^{1.72[ln hardness]-6.59} Silver, Chronic Not applicable Zinc, Acute WER*0.978 ∙ e^{0.8473[ln hardness]+0.884} Zinc, Chronic WER*0.986 ∙ e^{0.8473[ln hardness]+0.884} General Information on the Reasonable Potential Analysis (RPA) The RPA process itself did not change as the result of the new metals standards. However, application of the dissolved and hardness-dependent standards requires additional consideration in order to establish the numeric standard for each metal of concern of each individual discharge. The hardness-based standards require some knowledge of the effluent and instream (upstream) hardness and so must be calculated case-by-case for each discharge. Metals limits must be expressed as ‘total recoverable’ metals in accordance with 40 CFR 122.45(c). The discharge-specific standards must be converted to the equivalent total values for use in the RPA calculations. We will generally rely on default translator values developed for each metal (more on that below), but it is also possible to consider case-specific translators developed in accordance with established methodology. RPA Permitting Guidance/WQBELs for Hardness-Dependent Metals - Freshwater Renewal Fact Sheet - DRAFT 25May2023 NPDES Permit NC0090140 Page 6 The RPA is designed to predict the maximum likely effluent concentrations for each metal of concern, based on recent effluent data, and calculate the allowable effluent concentrations, based on applicable standards and the critical low-flow values for the receiving stream. If the maximum predicted value is greater than the maximum allowed value (chronic or acute), the discharge has reasonable potential to exceed the standard, which warrants a permit limit in most cases. If monitoring for a particular pollutant indicates that the pollutant is not present (i.e. consistently below detection level), then the Division may remove the monitoring requirement in the reissued permit. 1. To perform a RPA on the Freshwater hardness-dependent metals the Permit Writer compiles the following information: • Critical low flow of the receiving stream, 7Q10 (the spreadsheet automatically calculates the 1Q10 using the formula 1Q10 = 0.843 (s7Q10, cfs) 0.993 • Effluent hardness and upstream hardness, site-specific data is preferred • Permitted flow • Receiving stream classification 2. In order to establish the numeric standard for each hardness-dependent metal of concern and for each individual discharge, the Permit Writer must first determine what effluent and instream (upstream) hardness values to use in the equations. The permit writer reviews DMR’s, Effluent Pollutant Scans, and Toxicity Test results for any hardness data and contacts the Permittee to see if any additional data is available for instream hardness values, upstream of the discharge. If no hardness data is available, the permit writer may choose to do an initial evaluation using a default hardness of 25 mg/L (CaCO3 or (Ca + Mg)). Minimum and maximum limits on the hardness value used for water quality calculations are 25 mg/L and 400 mg/L, respectively. If the use of a default hardness value results in a hardness-dependent metal showing reasonable potential, the permit writer contacts the Permittee and requests 5 site-specific effluent and upstream hardness samples over a period of one week. The RPA is rerun using the new data. The overall hardness value used in the water quality calculations is calculated as follows: Combined Hardness (chronic) = (Permitted Flow, cfs *Avg. Effluent Hardness, mg/L) x (s7Q10, cfs *Avg. Upstream Hardness, mg/L) (Permitted Flow, cfs + s7Q10, cfs) The Combined Hardness for acute is the same but the calculation uses the 1Q10 flow. 3. The permit writer converts the numeric standard for each metal of concern to a total recoverable metal, using the EPA Default Partition Coefficients (DPCs) or site-specific translators, if any have been developed using federally approved methodology. Renewal Fact Sheet - DRAFT 25May2023 NPDES Permit NC0090140 Page 7 4. The numeric standard for each metal of concern is divided by the default partition coefficient (or site-specific translator) to obtain a Total Recoverable Metal at ambient conditions. In some cases, where an EPA default partition coefficient translator does not exist (ie. silver), the dissolved numeric standard for each metal of concern is divided by the EPA conversion factor to obtain a Total Recoverable Metal at ambient conditions. This method presumes that the metal is dissolved to the same extent as it was during EPA’s criteria development for metals. For more information on conversion factors see the June 1996 EPA Translator Guidance Document. 5. The RPA spreadsheet uses a mass balance equation to determine the total allowable concentration (permit limits) for each pollutant using the following equation: Ca = (s7Q10 + Qw) (Cwqs) – (s7Q10) (Cb) Qw Where: Ca = allowable effluent concentration (µg/L or mg/L) Cwqs = NC Water Quality Standard or federal criteria (µg/L or mg/L) Cb = background concentration: assume zero for all toxicants except NH3* (µg/L or mg/L) Qw = permitted effluent flow (cfs, match s7Q10) s7Q10 = summer low flow used to protect aquatic life from chronic toxicity and human health through the consumption of water, fish, and shellfish from noncarcinogens (cfs) * Discussions are on-going with EPA on how best to address background concentrations Flows other than s7Q10 may be incorporated as applicable: 1Q10 = used in the equation to protect aquatic life from acute toxicity QA = used in the equation to protect human health through the consumption of water, fish, and shellfish from carcinogens 30Q2 = used in the equation to protect aesthetic quality 6. The permit writer enters the most recent 2-3 years of effluent data for each pollutant of concern. Data entered must have been taken within four and one-half years prior to the date of the permit application (40 CFR 122.21). The RPA spreadsheet estimates the 95th percentile upper concentration of each pollutant. The Predicted Max concentrations are compared to the Total allowable concentrations to determine if a permit limit is necessary. If the predicted max exceeds the acute or chronic Total allowable concentrations, the discharge is considered to show reasonable potential to violate the water quality standard, and a permit limit (Total allowable concentration) is included in the permit in accordance with the U.S. EPA Technical Support Document for Water Quality-Based Toxics Control published in 1991. EPA default partition coefficients or the “Fraction Dissolved” converts the value for dissolved metal at laboratory conditions to total recoverable metal at in-stream ambient conditions. This factor is calculated using the linear partition coefficients found in The Metals Translator: Guidance for Calculating a Total Recoverable Permit Limit from a Dissolved Criterion (EPA 823-B-96-007, June 1996) and the equation: _Cdiss__ = _______1_______________ Ctotal 1 + { [Kpo] [ss(1+a)] [10-6] } Where: ss = in-stream suspended solids concentration [mg/l], minimum of 10 mg/L used, and Kpo and a = constants that express the equilibrium relationship between dissolved and adsorbed forms of metals. A list of constants used for each hardness-dependent metal can also be found in the RPA program under a sheet labeled DPCs. Renewal Fact Sheet - DRAFT 25May2023 NPDES Permit NC0090140 Page 8 7. When appropriate, permit writers develop facility specific compliance schedules in accordance with the EPA Headquarters Memo dated May 10, 2007 from James Hanlon to Alexis Strauss on 40 CFR 122.47 Compliance Schedule Requirements. 8. The Total Chromium NC WQS was removed and replaced with trivalent chromium and hexavalent chromium Water Quality Standards. As a cost savings measure, total chromium data results may be used as a conservative surrogate in cases where there are no analytical results based on chromium III or VI. In these cases, the projected maximum concentration (95th %) for total chromium will be compared against water quality standards for chromium III and chromium VI. 9. Effluent hardness sampling and instream hardness sampling, upstream of the discharge, are inserted into all permits with facilities monitoring for hardness-dependent metals to ensure the accuracy of the permit limits and to build a more robust hardness dataset. 10. Hardness and flow values used in the Reasonable Potential Analysis for this permit included: Parameter Value Comments (Data Source) Average Effluent Hardness (mg/L) [Total as, CaCO3 or (Ca + Mg)] TBD No discharge data to date Average Upstream Hardness (mg/L) [Total as, CaCO3 or (Ca + Mg)] TBD No monitoring data to date 7Q10 summer (cfs) 0.0 Storm-sewer discharge IWC = 100% 1Q10 (cfs) 0.0 Storm-sewer discharge IWC = 100% Permitted Flow (MGD) 0.075 Assumed monthly average.