NC0089958_Staff Report_20210910

State of North Carolina
Division of Water Resources
Water Quality Regional Operations Section
Environmental Staff Report
Quality
To: ® NPDES Unit ❑ Non -Discharge Unit Application No.: (NC0089958)
Attn: (Joe Corporon in Raleigh) Facility name: Central Square Excavation Dewatering
(Former Sherwin Williams BF Site)
From: (Edward Watson in Regional Office)
Mooresville Regional Office
Note: This form has been adapted from the non -discharge facility staff report to document the review of both non -
discharge and NPDES permit applications and/or renewals. Please complete all sections as they are applicable.
I. GENERAL AND SITE VISIT INFORMATION
1. Was a site visit conducted? ® Yes or ❑ No
a. Date of site visit: 08/30/2021
b. Site visit conducted by: Edward Watson
c. Inspection report attached? ❑ Yes or ® No
d. Person contacted: Joe Nestor, P.E., and their contact information: (704) 525 - 5152 ext.
e. Driving directions: From MRO office, travel South on Main St. for 2.7 miles to Langtree Rd. Travel for - 1.1
miles, then take on ramp. to I-77 on ramp South toward Charlotte. Drive S. on I-77 for —20 miles. To exit 11 to I-
277/NC-16 S to exit 3A toward Brevard/Davidson/McDowell St. for 0 .1 miles, then bear left onto E l lth St for .5
miles, the turn left on E loth St. for 0.5 miles bearing left onto Central Ave. 1314 Central Avenue is one of several
addresses that comprise the site location. Total driving distance to the site is —29 miles.
2. Discharge Point(s):001
Latitude: 35° 13' 25.0" Longitude: 80° 19' 07.7"
Latitude: Longitude:
3. Receiving stream or affected surface waters: UT to little Sugar Creek
Classification: C
River Basin and Subbasin No. 11-137-08
Describe receiving stream features and pertinent downstream uses: Urban stream in the Catawba River
Basin
II. PROPOSED FACILITIES: NEW APPLICATIONS
1. Facility Classification: Minor (Please attach completed rating sheet to be attached to issued permit)
Proposed flow:.050 MGD
Current permitted flow: New Application
2. Are the new treatment facilities adequate for the type of waste and disposal system? ® Yes or n No
If no, explain:
3. Are site conditions (soils, depth to water table, etc) consistent with the submitted reports? ❑ Yes ❑ No ❑ N/A
If no, please explain: Soil conditions were not examined as no open trenches were present to be able to observe
onsite soil conditions. Analysis was based on file review of multiple site soil borings.
FORM: WQROSSR 04-14 Page 1 of 3

4. Do the plans and site map represent the actual site (property lines, wells, etc.)? ® Yes ❑ No ❑ N/A
If no, please explain:
5. Is the proposed residuals management plan adequate? ❑ Yes No ® N/A
If no, please explain:
6. Are the proposed application rates (e.g., hydraulic, nutrient) acceptable? n Yes ❑ No ® N/A
If no, please explain:
7. Are there any setback conflicts for proposed treatment, storage and disposal sites? ❑ Yes or n No
If yes, attach a map showing conflict areas. N/A.
8. Is the proposed or existing groundwater monitoring program adequate? ❑ Yes ® No n N/A
If no, explain and recommend any changes to the groundwater monitoring program: Please refer to the
Additional Regional Office Comments for sampling recommendations.
9. 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: N/A.
10. Possible toxic impacts to surface waters: Chronic toxicity testing will be in place to monitor breakthrough of
Chlorinated Solvents being treated by the on -site system.
11. Pretreatment Program (POTWs only): N/A.
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
1
Information on the connection from the discharge line of the treatment
system to the UT — there are multiple options for routing the discharge line to
the outfall and the permittee needs to decide the final route and let us know.
2
Please install a sampling port after treatment and before discharge into the
storm drain to be able to collect a representative effluent sample and avoid
surface water run-off interference.
3
Please provide a map that displays the location of the treatment system
associated wells. The map should also display topographic overlay indicating
direction of GW flow.
4
Please provide an Iso-contour maps of the constituents of concern to be treated
by the system.
3. List specific permit conditions recommended to be removed from the permit when issued:
Condition
Reason
FORM: WQROSSR 04-14
Page 2 of 3

4. List specific special conditions or compliance schedules recommended to be included in the peniiit when issued:
Condition
Reason
1
Wet Toxicity due to the presence of Chlorinated solvents.
2
Modified RCRA Metal for Chromium and Arsenic
5. 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: )
6. Signature of report preparer: Edward Watson, Hydrogeologist 09/10/2021.
�DocuSigned by:
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7. Signature of regional supervisor: Date:
ADDITIONAL REGIONAL STAFF REVIEW ITEMS
9.10.21
There is a lot of activity located nearby the subject site. A review of the DWM Site Locator Tool indicates several potential sources of
contaminants near the subject site. Site Assessment documents were reviewed along with GW and Soil chemistry that was available
in the application. The information for these nearby sites appears that there were several gas stations and automotive service facilities
with former USTs. Many of these facilities have received NFA status from DWM.
GW and Soil analytical data do not indicate petroleum constituents present at levels above 2L or PSRG Soil Standards. TW-2 reports
the presence of dibromochloromethane. However, the level is below the 2L standard.
Waivers have been requested for certain constituents in the application. A review of the constituents sampled in GW and SS indicate
that absence of pesticides throughout the subject site.
A waiver was also requested to remove metals sampling. A review of the site reports indicates the presence of Chromium in several
soil sample and GW samples. Arsenic was present above PSRG Soil Standard in SB-1, SB-2, SB-3, and SB-4 in report
IH3129 20201230 SAR BF Limited Env. Assessment.
The applicant is also requesting the following sampling parameters to be waived for the permit:
• BOD
• COD
• TOC
• NH3
• TEMP SEASONAL
And the MRO is comfortable with those constituents being removed.
FORM: WQROSSR 04-14 Page 3 of 3