WQ0023896_Summary of historical fecal coliform results._20240119

Baker, Caroline D
From:
Daw, Larry <[e-mail]>
Sent:
Friday, January 19, 2024 9:49 AM
To:
Hall, Michael
Cc:
Manuel, Vanessa; Clark, Timothy W
Subject:
RE: [External] UNC Bingham Facility - Ground water constituents exceeding standards
December 2023
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Thanks for your reply.
We are going to continue to use the new sampling approach for the next one or two sampling events and see if anything
changes. We are hoping we can get away with no irrigation in Field 4 for a while so that we can eliminate irrigation of
that field as a variable (depends on how much water we need to get rid of).
Historically, we have seen fecal levels vary widely, from zero and low numbers to quite high numbers. See below.
Fecal (per 100ml)
Fecal (per 100ml)
MW-3
MW-4
3/21/2014
<1
<1
6/12/2014
1
14
9/12/2014
4
3
12/4/2014
100
100
3/9/2015
<1
2
6/1/2015
<1
<1
9/14/2015
37
35
12/10/2015
<1
2
3/7/2016
<1
<1
6/8/2016
82
270
9/8/2016
3
6
12/15/2016
2
1
3/16/2017
<1
2
6/21/2017
49
290
9/7/2017
7
240
12/1/2017
1
2
3/9/2018
<1
4
6/8/2018
<1
<1
9/27/2018
12
210
12/6/2018
<1
7
3/14/2019
<1
<1
6/11/2019
10
64
9/13/2019
<1
<1
12/10/2019
3
1
3/13/2020
<1
<1
1

6/12/2020
12
11
9/10/2020
<1
3
12/3/2020
<1
22
3/4/2021
1
<1
6/7/2021
2
<1
9/9/2021
<1
11
12/7/2021
<1
2
3/17/2022
2
<1
6/10/2022
<1
2
9/15/2022
<1
<1
12/2/2022
<1
1
3/6/2023
<1
<1
6/8/2023
<1
4
9/5/2023
<1
230
12/8/2023
1
2
We will put a little more effort into resolving this question. As I mentioned before, our earlier DEQ contact (Ray MiIosh)
and I put a considerable amount of thought and discussion into the occurrence of fecal at this facility and could not
come up with a firm conclusion.
Thanks again.
Larry Daw, L.G.
Environmental Compliance Officer I Geophysicist I Licensed Geologist
INSTItUTIONAt INTEGR17YAND RISKMAN AGE MENT
LIT UNC � Environment, Health and Safety
THE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL
ENVIRONMENT, HEALTH & SAFETY
1120 Estes Drive I Campus Box 1650 1 Chapel Hill, NC 27599-16501 www.ehs.unc.edu
Office: 919.962.6666 1 Mobile: [phone] Email: [e-mail]
From: Hall, Michael <[e-mail]>
Sent: Friday, January 19, 2024 9:25 AM
To: Daw, Larry <[e-mail]>
Cc: Manuel, Vanessa <[e-mail]>; Clark, Timothy W <[e-mail]>
Subject: RE: [External] UNC Bingham Facility - Ground water constituents exceeding standards December 2023
Larry
Good morning. I appreciate the update, and I am sorry that the peristaltic pumping and other measures did not
eliminate the coliform issue. At least, it appears that the concentrations are low. This is such a finicky test. I still
suspect that the detections are because of cross contamination, and may even be wind -born. In light of the generally
well -managed system, low volume of effluent, and absence of other exceedances, we will make a note that these
coliform exceedances do not appear to be related to the operation of the WWTF. Please continue to report these
exceedances as you have previously, and we will make a note in the database with regard to our interpretation.
Regards
F)

Mike Hall, PG (he/him/his)
Geologist/Hydrogeologist
Division of Water Resources, Raleigh Regional Office
Department of Environmental Quality
Office: [phone] 1 Cell: [phone]
[e-mail]
Physical: 3800 Barrett Drive, Raleigh, NC 27609
Mailing: 1628 Mail Service Center, Raleigh, NC 27699-1628
D 0
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ki;
NORTH CAROLINA
Department of Environmental Quality
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Carolina Public Records Law and may be disclosed to third parties.
From: Daw, Larry <[e-mail]>
Sent: Thursday, January 18, 2024 11:27 AM
To: Hall, Michael <[e-mail]>
Cc: Manuel, Vanessa <[e-mail]>
Subject: [External] UNC Bingham Facility - Ground water constituents exceeding standards December 2023
CAUTION: External email. Do not click links or open attachments unless verified. Report suspicious emails with the Report Message
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Mike,
We completed permit required groundwater sampling at the UNC Bingham Facility on December 8, 2023, and the
following constituents exceed standards:
12-8-2023 MW-3 pH 5.9 SU
12-8-2023 MW-3 Fecal Coliform 1 colonies/100 ml
12-8-2023 MW-4 pH 6.2 SU
12-8-2023 MW-4 Fecal Coliform 2 colonies/100 ml
Prior to this sampling event all groundwater sampling was conducted using bailers. For the December 2023 sampling
event, a peristaltic pump was used to purge and sample MW-3 and MW-4. A peristaltic pump was initially used during
purging of MW-5; however, pumping quickly drew down the water level below that which the pump functioned. Further
purging and sampling of MW-5 was completed by bailing. Bailers were used to purge and sample MW-1 and MW-6.
Extraordinary care was taken to minimize cross contamination of water samples. The peristaltic pump and other
sampling equipment were decontaminated prior to first use and between wells. New tubing was used for each
well. Gloves were worn and changed on a regular basis.
Even with these changes to sampling procedures, we continue to see fecal in MW-3 and MW-4. MW-4 is upgradient and
MW-3 is downgradient of Field 4, and no irrigation has occurred in Field 4 since October 4, 2023, over 9 weeks prior to
this sampling event.

We will continue to use the modified sampling procedure for the next sampling event and see if there are any changes in
the trends of fecal in these wells. Please let me know if you have any questions or comments. Thank you.
Larry Daw, L.G.
Environmental Compliance Officer I Geophysicist I Licensed Geologist
Q-T
INSTITUTIONAL I N TEG RITY AN D RI SK MAN AGE MENT
U N C I Environment, Health and Safety
THE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL
ENVIRONMENT, HEALTH & SAFETY
1120 Estes Drive I Campus Box 1650 1 Chapel Hill, NC 27599-16501 www.ehs.unc.edu
Office: 919.962.6666 1 Mobile: [phone] Email: [e-mail]
Email correspondence to and from this address may be subject to the North Carolina Public Records Law and may be disclosed to third parties by an authorized
state official.