4903_IredellMSW_Phase6PrelimBoringPlanEmail_DIN28088_20170630

1
Sugg, William P
From:Sugg, William P
Sent:Friday, June 30, 2017 2:17 PM
To:'Jonathan Pfohl'
Subject:RE: Iredell Co MSWLF (49-03) Proposed Ph 6 Design Hydro Boring Plan Review Request
Attachments:4903 - Iredell Ph 6 Prelim Boring Plan Sheets 1 and 2.pdf
Jonathan,
I’ve reviewed your preliminary spacing and total number of borings proposed for Phase 6 as depicted on the
figures (attached) you submitted in your email request on June 6, 2017. Note that boring clusters (ie, adjacent
deep and shallow borings) are considered as one boring location for spatial density determinations. Also, for
purposes of planning the required number of borings per .1623(b)(1), the 'area of investigation' for most sites
will generally be comprised of the landfill footprint unless otherwise determined by the Division. In the
proposed boring plan for Phase 6, there are 29 boring locations within the 41-acre footprint, for a boring
density of about 0.7 borings/acre (or, one boring location/1.4 acres). This boring density remains consistent
when extending the area out to the 125-ft review boundary.

For an appropriate boring density less one boring/acre, the Section can consider other factors. For this site, we
reviewed and considered: previous design data collected at the facility for adjacent landfill units Phases 1-5;
information on subsurface conditions exposed during past construction grading for these phases; and the
proximity of Phase 6 to these constructed phases. Based on these factors, the proposed boring plan appears to
be appropriate for the site.

Note that SWS reserves the right to request additional information upon review of the Design hydro report, as
each site can contain its own extraneous circumstances. Regardless of minimum boring density requirements,
it is ultimately incumbent upon the design engineer and hydrogeologist to adequately evaluate the hydro and
subsurface site conditions for design considerations consistent with rules requirements (including vertical
separation, foundation standards, effective water quality monitoring system and more).

If you have any further questions, please feel free to call. Thank you.

Perry Sugg, PG
Permitting Hydrogeologist
Division of Waste Management – Solid Waste Section
NC Department of Environmental Quality
Phone: [phone]
[e-mail]

Physical Address: 217 West Jones St / Raleigh, NC / 27603
Mailing Address: 1646 Mail Service Center / Raleigh, NC / 27699-1646
http://portal.ncdenr.org/web/wm/sw

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following three fundamental principles are integral components of its protective mandate: Fundamental Philosophy, Fundamental Economics, and Fundamental
Science. Ultimately, a collaborative stewardship among the citizens, government regulators, and the business community will maintain and enhance North Carolina's environment and
natural resources for the benefit and enjoyment of everyone living in or visiting our Great state.

E-mail correspondence to and from this addresss may be subject to the North Carolina Public Records Law and therefore may be disclosed to third parties.

2
From: Jonathan Pfohl [mailto:[e-mail]]  
Sent: Tuesday, June 06, 2017 4:26 PM 
To: Sugg, William P <[e-mail]> 
Subject: Iredell Co MSWLF (49‐03) Proposed Ph 6 Design Hydro Boring Plan Review Request 

I am sending you this email on the premise that you expect to be (> year from now) the reviewer of a
hydrogeologic Design Study (HGDS) report for Iredell County proposed Ph 6.
If you expect not to review this report would you please let us know whom will and/or forward this email to
them.

Attached is a preliminary boring plan layout Sheet 1 (Topo) and Sheet 2 (Aerial) proposed for Ph 6 HGDS
which is planned to encompass 41 acres.
In 2010 a HGDS was performed for Phase 5 and ~21 acres of Phase 6. However, only Ph 5 was constructed
and is in operation.
We plan to expand the study area another ~20 acres in the northern direction for Ph 6 which will comprise 41
acres.
The plan includes 55 borings (a mix of abandoned, existing & proposed new wells).
We seek assurance from the SWS that the density and locations appear to be sufficient.
Rule 15A NCAC13B.1623 (b) (1) indicates the required boring density is based upon "area of investigation"
which is open for your interpretation.
We want to proactively avoid a situation that after the HGDS is submitted that the SWS ultimately finds the
density to be deficient leaving us to install more wells and continue the study.

Total observation wells planned to use in HGDS=55
Proposed footprint=~41 acres (1.34 boring/acre density)
Proposed footprint plus 125' review boundary =57 acres (0.97 boring/acre density)
Of the 55 borings 12 are abandoned wells, 29 are existing wells & 14 new wells are proposed.
The study will entail 10 cluster pairs (vertical hydraulic gradients), Rock cored > 10 feet at 8 locations,
additionally bedrock will be tagged at 6 locations.
At least 14 soil samples will be lab tested from both vadose and within the uppermost aquifer.

A soil stockpile and mulching operations exists within the proposed footprint. Some of the boring locations (ie
OW6-9S/D) may need to be moved slightly depending upon status of the stockpiles but the density plans to
remain.

Please let me if the SWS considers this boring plan satisfactory in terms of density and spacing so we can
mobilize.
Simply call anytime if you have any questions, need any clarifications or would like to provide any
recommendations that will aid in this impending HGDS.

Thanks,
Jonathan

--
Jonathan Pfohl
Municipal Engineering Services, Co. PA
PO Box 97 Garner NC 27529
68 Shipwash Dr. Garner NC 27529
Office: [phone]
Mobile: [phone]
MW-1C
P2-1S
PZ-1S
PZ-1D (R)
P5-1
LINED MSWLF PHASE 5
MW-35
P-77
P5-4
P5-2S
P5-7
P5-13
P5-6
MW-34
P5-15S
P5-15D (CR)
P5-19
P5-20
MW-33S
MW-33D (CR)
P5-2D (CR)
P5-3
P5-8
P5-9SP5-9D (CR)
POND
ACTIVE PTO 11/18/14
MW-1A
P2-1D (R)
P-78SP-78D (CR)P5-18
P5-17OW6-1
OW6-2
OW6-3
OW6-4
OW6-5
OW6-6
P-2 (R)
OW6-8S
OW6-9
OW6-8D (CR)OW6-10
OW6-11 (R)
OW6-12
OW6-13 (CR)
OW6-7D (CR)
SOIL STOCKPILE #2
(EXISTING)
P2-3D (R)
P2-3
(C)
(R)
Preliminary boring density summary
TOTAL WELLS PROPOSED TO BE USED IN PH 6 STUDY55
PROPOSED PH 6 FOOTPRINT (FP) (41 ACRES)
TOTAL WELLS IN FP
11 20 4 35
REVIEW BOUNDARY (RB) (125' from FP) (57 ACRES)
3 6 4 13
COMPLIANCE BOUNDARY (CB) (<300' OF FOOTPRINT) (76 ACRES)
TOTAL WELLS WITHIN CB
0 3 4 7
Iredell Co. MSWLF, Ph 6 Proposed
NEW WELLS PROPOSED IN FP
EXISTING WELLS STILL IN FP
ABANDONED WELLS IN FP
NEW WELLS PROPOSED IN RB
EXISTING WELLS STILL IN RB
ABANDONED
WELLS IN RB
NEW WELLS PROPOSED IN CB
EXISTING WELLS STILL IN CB ABANDONED WELLS IN CB
TOTAL WELLS WITHIN RB
P5-11
P5-10
MW-1C
P2-1S
PZ-1S
PZ-1D (R)
P5-1
LINED MSWLF PHASE 5
MW-35
P-77
P5-4
P5-2S
P5-7
P5-13
P5-6
MW-34
P5-15S
P5-15D (CR)
P5-19
P5-20
MW-33S
MW-33D (CR)
P5-2D (CR)
P5-3
P5-8
P5-9SP5-9D (CR)
POND
ACTIVE PTO 11/18/14
MW-1A
P2-1D (R)
P-78SP-78D (CR)P5-18
P5-17OW6-1
OW6-2
OW6-3
OW6-6
P-2 (R)
OW6-8S
OW6-9
OW6-8D (CR)OW6-10
OW6-11 (R)
OW6-12
OW6-13 (CR)
OW6-7D (CR)
SOIL STOCKPILE #2
(EXISTING)
P2-3D (R)
P2-3
(C)
(R)
Preliminary boring density summary
TOTAL WELLS PROPOSED TO BE USED IN PH 6 STUDY55
PROPOSED PH 6 FOOTPRINT (FP) (41 ACRES)
TOTAL WELLS IN FP
11 20 4 35
REVIEW BOUNDARY (RB) (125' from FP) (57 ACRES)
TOTAL WELLS WITHIN RB
3 6 4 13
COMPLIANCE BOUNDARY (CB) (<300' OF FOOTPRINT) (76 ACRES)
TOTAL WELLS WITHIN CB
0 3 4 7
Iredell Co. MSWLF, Ph 6 Proposed
NEW WELLS PROPOSED IN FP
EXISTING WELLS STILL IN FP
ABANDONED WELLS IN FP
NEW WELLS PROPOSED IN RB
EXISTING WELLS STILL IN RB
ABANDONED
WELLS IN RB
NEW WELLS PROPOSED IN CB
EXISTING WELLS STILL IN CB ABANDONED WELLS IN CB
OW6-4
OW6-5
P5-11P5-11
P5-10
B-79