NCG551535_Lab Data_20231130

awa Stormwater Services Group, LLC
8916 Oregon Inlet Court
Raleigh, North Carolina 27603
Phone: [phone]
Fax: [phone]
November 21, 2023
Jane Bernard
Raleigh RO — Surface Water Protection
NC Division of Environmental Quality
1628 MSC
Raleigh NC 27699-1628
RE: 6917 Kemp Rd, Durham NC
NPDES General Permit NCG551535
Dear Ms. Bernard:
In response to NOV-2022-PC-0235 dated April 26, 20221, we have collected a discharge sample from the sand filter and have
analyzed it for the parameters indicated in the NOV letter. The results are as follows:
Table 1 — Effluent Analysis Results
Outfall
Date
Flow,
Gals/ Day
(est)
BOD5,
mg/L
TSS,
mg/L
pH,
Std. Units
Total
Residual
Chlorine,
ME&
Fecal
coliform,
MPN/ 100
mL
Limits
1000
45.0
45.0
6.0 - 9.0
0.017'
400
Sand Filter
11 /06/23
200
46.8
43.3
6.85
> 5.00
49.6
The original addressee died prior to complying with the NOV. The new property owners are providing this follow-up response letter.
Z Receiving stream chlorine levels are not to exceed 17 µg/L. Sample is taken at end of effluent pipe. Flow from effluent pipe is not connected to surface waters
of the State; flow disperses into a grass and wooded buffer and infiltrates into the ground. The nearest Waters of the State is about 380 meters from the effluent
pipe outlet.

NCDEQ
November 21, 2023
Page 2
Today's flow rate is estimated based on two (2) adults and two (2)
children living at the residence using 50 gals/ day/ person. This flow
rate is probably over -estimated as there is at most a low trickle flow3
from this system unless we surcharge the sand filter by running the cold
water faucet at the bathtub for at least 25 minutes.
Note that there is no direct discharge from this system into "waters of
the State. " Flow from this system is dispersed onto a grassy slope then
into a wooded buffer. The receiving "blue line" stream (Laurel Creek) is
about 380 meters to the northwest.
The original laboratory report and chain -of -custody form is maintained
at the residence.
The next effluent sample will be collected and analyzed in Yd Quarter
2024. In the meantime, if you have any questions, do not hesitate to call
me.
Sincerely,
STOPWfTER SERVICES GROUP, LLC
Alv-
es D. Frei
Senior Project Manager
cc: Buh Re (property owner)
File
3 There was a very low trickle flow upon arrival at the residence.
Swl%
Figure I - Effluent Pipe before surcharging
No flow upon arrival at effluent pipe. Evidence of prior flow is
present.