NCG080840_BENCHMARK EXCEEDANCE_20201230

Charlotte -Mecklenburg
Tuli 600 E, Fourth Street
Charlotte, NC 28202
Fax 704.336,6586
Services -'
December 23, 2020
NC Department of Environmental Quality
Division of Energy, Mining, and Land Resources
Attention: Mr. Zahid Khan
610 E. Center Ave, Suite 301
Mooresville, NC 28115
Re: Tier III Status of Outfall 2 at City of Charlotte Heavy Equipment Shop
NPDES Industrial Stormwater Permit NCG080840
Dear Mr. Khan,
The permit benchmark for Total Suspended Solids (TSS) has been exceeded at Outfall 2
at the City of Charlotte's Heavy Equipment Shop more than four times since permit
coverage began on November 1, 2018. The following summarizes the benchmark
exceedances since that date (benchmark for TSS is 100 mg/L).
Date
Result m /L)
12/20/18
250
1/29/19
120
4/2/19
320
11/27/19
250
3/3/20
700
8/3/20
106
Please note that Outfall 2 has been in Tier II since the new permit coverage began due to
carryover from the previous permit term, so monthly monitoring has been ongoing since
then. During some months there was no discharge and some months the result for TSS
was below the benchmark.
Quite a few measures have been undertaken to reduce TSS discharges at the site
including lot and manual sweeping, use of various catch basin filters with cleaning and
maintenance performed by a contractor, pothole repairs, videoing pipes, and
repairing/rebuilding several catch basins that were failing and causing erosion.
Currently a lot repaving project is being planned and staff are working with HDR on
feasibility of installing structural stormwater control measures. Preliminary design plans
have been developed and reviewed with next steps being additional vetting of design and
cost estimates as well as determining cost/benefit of the SCMs and overall feasibility.
•
CHARWIT1;.. To report pollution or drainage problems, call: 311
http://stormwater.charmeck.org

Mr. Zahid Khan
December 23, 2020
We will continue to conduct monthly monitoring until three consecutive results are below
the benchmark. We will also continue working on the two projects discussed briefly
above.
Please contact me at cmmiller2ccharlottenc.gov or [phone] if you wish to discuss
this matter further.
Sincerely,
6 � 4
j�
Craig Miller
NPDES Permit Supervisor
City of Charlotte Storm Water Services
cc: James Moore
2