NC0089923_Staff Report_20200701

State of North Carolina
Nr Division of Water Resources
" Water Quality Regional Operations Section
Environmental Staff Report
Quality
To: ® NPDES Unit ❑ Non -Discharge Unit
Attn: (NPDES Permitting Group)
From: (Edward Watson in)
Mooresville Regional Office
Application No.: (NC0089923)
Facility name: Baxter St. GW Remediation System
Note: This form has been adapted from the non -discharge fg acili , staff report to document the review of both non -
discharge and NPDES permit applications and/or renewals. Please complete all sections as they are gpplicable.
I. GENERAL AND SITE VISIT INFORMATION
1. Was a site visit conducted? ® Yes or ❑ No
a. Date of site visit: 0611612020
b. Site visit conducted by: Inspection report attached? ❑ Yes or ® No
c. Person contacted: Bruce Reilly and their contact information: (980) 260 - 2130 ext.
e. Driving directions: Travel to 1-77 South for 28 miles. Take Exit 10A for US 29/NC-27/Morehead St. After 0.2
miles turn left onto Morehead St. After 0.8 miles, merge onto E. Morehead St. Travel on E. Morehead St for 0.6
miles and turn left onto Baxter St. The treatment system is location at the south end of Baxter St.
2. Discharge Point(s):
Outfall 001: Latitude: 350 12' 49.151" N Longitude: 80' 50' 26.943" W
Outfall 002: Latitude: 350 12' 52.8777" N Longitude:800 50' 36.222" W
3. Receiving stream or affected surface waters: Little Sugar Creek
Classification: C (fishable/swimmable) water within the Catawba basin
River Basin and Subbasin No.: Catawba, Lower Catawba 03050103
Describe receiving stream features and pertinent downstream uses: Conveyance to Little Sugar Cr.
II. PROPOSED FACILITIES: NEW APPLICATIONS
1. Facility Classification: (Please attach completed rating sheet to be attached to issued permit)
Proposed flow: 0.036MGD
Current permitted flow: None.
2. Are the new treatment facilities adequate for the type of waste and disposal system? ® Yes or ❑ No
If no, explain: Are site conditions (soils, depth to water table, etc.) consistent with the submitted reports? ® Yes
❑ No ❑ N/A If no, please explain:
3. Do the plans and site map represent the actual site (property lines, wells, etc.)? ® Yes ❑ No ❑ N/A
If no, please explain:
4. Is the proposed residuals management plan adequate? ❑ Yes ❑ No ® N/A
If no, please explain:
5. Are the proposed application rates (e.g., hydraulic, nutrient) acceptable? ❑ Yes ❑ No ® N/A
If no, please explain:
FORM: WQROSSR 04-14 Page 1 of 4

6. Are there any setback conflicts for proposed treatment, storage and disposal sites? ❑ Yes or ® No
If yes, attach a map showing conflict areas.
Is the proposed or existing groundwater monitoring program adequate? ❑ Yes ❑ No ® N/A
If no, explain and recommend any changes to the groundwater monitoring program: Effluent monitoring will be
conducted post treatment.
8. For residuals, will seasonal or other restrictions be required? ❑ Yes ❑ No ® N/A
If yes, attach list of sites with restrictions (Certification B)
Describe the residuals handling and utilization scheme:
9. Possible toxic impacts to surface waters: Breakthrough of treatment releasing dissolved chlorinated solvents into
an impaired stream.
10. Pretreatment Program (POTWs only): N/A
11. Are the monitoring well coordinates correct in BIMS? ❑ Yes ❑ No ® N/A
If no, please complete the following (expand table if necessary): There are existing wells on the site. None of
these wells are connected to the GW Treatment system.
12. Has a review of all self -monitoring data been conducted (e.g., DMR, NDMR, NDAR, GW)? ® Yes or ❑ No
Please summarize any findings resulting from this review: GW analytical data was supplied as part of the
application review indicating a plume of chlorinated solvents and petroleum related compounds.
Provide input to help the permit writer evaluate any requests for reduced monitoring, if applicable.
13. Are there any permit changes needed in order to address ongoing BIMS violations? ❑ Yes or ® No
If yes, please explain:
14. Check all that apply: This is an application for a new treatment system.
® No compliance issues ❑ Current enforcement action(s) ❑ Currently under JOC
❑ Notice(s) of violation ❑ Currently under SOC ❑ Currently under moratorium
Please explain and attach any documents that may help clarify answer/comments (i.e., NOV, NOD, etc.)
If the facility has had compliance problems during the permit cycle, please explain the status. Has the RO been
working with the Permittee? Is a solution underway or in place?
Have all compliance dates/conditions in the existing permit been satisfied? ❑ Yes ❑ No ® N/A
If no, please explain:
15. Are there any issues related to compliance/enforcement that should be resolved before issuing this permit?
❑ Yes ®No❑N/A
If yes, please explain:
16. Possible toxic impacts to surface waters: The release of dissolved chlorinated solvents and BTEX suite
constituents that could enter surface water through the storm drain if the system fails.
FORM: WQROSSR 04-14 Page 2 of 4

III. REGIONAL OFFICE RECOMMENDATIONS
1. Do you foresee any problems with issuance/renewal of this permit? ❑ Yes or ® No
If yes, please explain:
2. List any items that you would like the NPDES Unit or Non -Discharge Unit Central Office to obtain through an
additional information request:
Item Reason
3. List specific special conditions or compliance schedules recommended to be included in the permit when issued:
Condition
Reason
1
Wet Toxicity sampling to monitor effluent water being released to Little Sugar Creek,
which is an impaired stream.
2
Turbidity of no greater than 50NTU
3
4. Recommendation: ❑ Hold, pending receipt and review of additional information by regional office
❑ Hold, pending review of draft permit by regional office
❑ Issue upon receipt of needed additional information
® Issue
❑ Deny (Please state reasons: )
5. Signature of report preparer: Edward Watson June 30, 2020.
Signature of regional supervisor:
Date:
Docu Signed by:
p44" H P, 444 7.1. 2020
F161FB69A2D84A3...
FORM: WQROSSR 04-14 Page 3 of 4

IV. ADDITIONAL REGIONAL STAFF REVIEW ITEMS
Groundwater treatment is expected to only be in place during the construction phase of the work. This is estimated to be
approximately six months. The treatment system will be placed on a mobile platform so it can be transported across the
site. The mobility of the system is the reason for the second outfall location.
Facility site map and outfall locations are attached as PDF documents.
The receiving stream, Little Sugar Cr., is listed as an impaired waterway on the North Carolina 303(d) List.
Sampling data from monitoring wells resulted in values that exceed both the 2L and 2B standards for various chlorinated
solvents and petroleum constituents.
Little Sugar Creek has a TMDL to include a Fecal Coliform limit< 9.4 X 1012 cfu/100.
CEC reviewed Low -Flow Characteristics of Streams, for flow data for Little Sugar Creek.
Drainage Area: 40.80 sq. mi.
Summer/Winter 7Q10 Flow: 34cfs
30Q2 Flow: 87 cfs
Average annual unit runoff 12 cfs/sq. mi
System will need to be classified and appropriate ORC and backup ORC assigned prior to operation.
FORM: WQROSSR 04-14 Page 4 of 4