2906_DavidsonCo_CDLF_ResponsetoComment_DIN27986_20170619

June 19, 2017

Mr. Ming-Tai Chao, P.E.
Environmental Engineer
NC DEQ - Division of Waste Management
1646 Mail Service Center
Raleigh, NC 27699-1646
[e-mail]

RE: Davidson County C&D Landfill (Permit No. 29-06-CDLF)
Closure CQA Report
Response to Review Comments

Mr. Chao:

On behalf of Davidson County, Smith Gardner, Inc. (S+G) would like to respond to the
comments in your email dated and received by S+G on May 22, 2017 (see attached) related to
the construction quality assurance (CQA) report for the closure of the County’s construction
and demolition debris (C&D) landfill unit. Your comments are repeated below in italics
followed by our response in bold.

1. (Section 5.2)
a. The closed area for the C&DLF is approximately 7.6 acres as reported in
Section 1.0. This section records the earthen material of 21,200 cubic yards
(CY) was used to construct the two-feet vegetative soil layer; back-calculation
of the extent of the closed area, based on the data from the CQA Report,
shows the closed area is approximately 6.57 acres. If the closed area is 7.6
acres, should the soil volume for the 2-foot vegetative soil layer be
approximately 24,523 cy? Please clarify.

The quantity of 21,200 CY stated in the report is based on the estimated
quantity of soil which was placed by the contractor (Jimmy R. Lynch & Sons).
The County had previously placed a portion of the vegetative cover soils.

b. If the amount of soil of 21,200 CY is correct, the number of testing of Atterberg
Limits (ASTM D 4318) shall be five (5) according to the testing frequency in
Table 9.1 of the approved CQA Plan (DIN 26957). Appendix E -Earth Work CQA
Data only provide four (4) Atterberg Limits test results. Please provide the
missing data.

As noted above, the additional quantity of vegetative cover soil was placed by
the County. These soils came from the same on-site borrow source as the
soils used by the contractor and were visually observed by S+G to be similar
materials prior to the placement of additional soil. Thus, additional testing
did not appear warranted.
DocuSign Envelope ID: 9F3D8A7D-3D91-4222-A1CF-408B4738DB1A
Mr. Ming-Tai Chao, P.E.
June 19, 2017
Page 2 of 3
2. (Section 7.3) The quantity of LLDPE received for the project is 3 roll/1 lot and 51,060
square feet (SF) according to the Agru shipping document. The stated 51,750 SF in
this section is likely a typo. Please verify.

Section 7.3, Table 2, and the geomembrane inventory (Appendix G2) have been
revised to reflect the correct total of 51,060 SF.

3. (Appendix G)
a. According the approved Technical Specification Section 02778, Paragraph
C.2.b., please provide the copy of manufacturer’s and workmanship
warranties to the CQA report.

A copy of these warranties have been added as Appendix G6.

b. According the approved Technical Specification Section 02778, Paragraph
D.3.b. & Section 5.3.2 of the CQA Plan, please provide the copy of the LLDPE
prepared subgrade / surface of the intermediate soil layer acceptance form to
the CQA report.

A copy of this form has been added to Appendix G4.

c. According to Agru shipping paper (Doc# 35927) the resin lot # is CGK810470
for the 3 rolls of 40-mil LLDPE used in the project, but the Oven-aging test
and UV-aging test done by Chevron Philips are on material with different Lot #
or Roll #. Please clarify.

Per GRI Test Method GM-17, testing requirements for oven-aging and UV-
aging are per each formulation of resin which is less frequent than every
resin lot.

d. The seam number P10-12 has been repeated in the Non-Destructive Testing
Form; it is likely that one of them is a typo of P11-12, which is not available in
the form.

Seam P10-12 was tested in 2 segments (reference far right hand column on
the non-destructive testing form). Also, test information for P11-12 is shown
in the fourth row of the data on the form.

Please find enclosed a revised CQA report reflecting the changes described above. Please
contact Mr. Scheer at your earliest convenience if you should have any questions or
comments on this submittal.

DocuSign Envelope ID: 9F3D8A7D-3D91-4222-A1CF-408B4738DB1A
Mr. Ming-Tai Chao, P.E.
June 19, 2017
Page 3 of 3
Sincerely,
SMITH GARDNER, INC.

Byron S. Hackney Pieter K. Scheer, P.E.
Field Services Manager Vice President, Senior Engineer
[e-mail] [e-mail]

Attachment: DWM Comments (May 22, 2017 Email)

Enclosure: Revised C&DLF Closure CQA Report

cc: Rex Buck, Davidson County
Steven Sink, Davidson County
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6/19/2017

This page intentionally left blank.
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1
Pieter Scheer
From:Chao, Ming-tai
Sent:Monday, May 22, 2017 11:26 AM
To:Pieter Scheer
Cc:Buck, Rex; Sink, Steven; Heim, Susan A
Subject:Comments on Davidson County C&D Landfill (Permit No. 2906-CDLF) Closure - CQA
Report
Follow Up Flag:Follow up
Flag Status:Flagged
Hi Pieter:

The Solid Waste Section completes a review of the certified CQA Report (DIN 27735) of the above-referenced
landfill and has several comments (DIN 27813) stated below:

DIN 27813
1. (Section 5.2)
a. The closed area for the C&DLF is approximately 7.6 acres as reported in Section 1.0. This section
records the earthen material of 21,200 cubic yards (CY) was used to construct the two-feet
vegetative soil layer; back-calculation of the extent of the closed area, based on the data from the
CQA Report, shows the closed area is approximately 6.57 acres. If the closed area is 7.6 acres,
should the soil volume for the 2-foot vegetative soil layer be approximately 24,523 cy? Please
clarify.

b. If the amount of soil of 21,200 CY is correct, the number of testing of Atterberg Limits (ASTM D
4318) shall be five (5) according to the testing frequency in Table 9.1 of the approved CQA Plan
(DIN 26957). Appendix E -Earth Work CQA Data only provide four (4) Atterberg Limits test
results. Please provide the missing data.

2. (Section 7.3) The quantity of LLDPE received for the project is 3 roll/1 lot and 51,060 square feet (SF)
according to the Agru shipping document. The stated 51,750 SF in this section is likely a typo. Please
verify.

3. (Appendix G)
a. According the approved Technical Specification Section 02778, Paragraph C.2.b., please provide the
copy of manufacturer’s and workmanship warranties to the CQA report.

b. According the approved Technical Specification Section 02778, Paragraph D.3.b. & Section 5.3.2 of
the CQA Plan, please provide the copy of the LLDPE prepared subgrade / surface of the
intermediate soil layer acceptance form to the CQA report.

c. According to Agru shipping paper (Doc# 35927) the resin lot # is CGK810470 for the 3 rolls of 40-
mil LLDPE used in the project, but the Oven-aging test and UV-aging test done by Chevron Philips
are on material with different Lot # or Roll #. Please clarify.

DocuSign Envelope ID: 9F3D8A7D-3D91-4222-A1CF-408B4738DB1A
2
d. The seam number P10-12 has been repeated in the Non-Destructive Testing Form; it is likely that
one of them is a typo of P11-12, which is not available in the form.

Please contact me if you have any questions on the above-mentioned comments. Have a wonderful day.

Ming Chao
Ming-Tai Chao, P.E.
Environmental Engineer
Permitting Branch, Solid Waste Section
NCDEQ, Division of Waste Management
(Mailing Address)
1646 Mail Service Center
Raleigh, NC 27699-1646

(Street Address)
Green Square, 217 West Jones Street
Raleigh, NC 27603
Tel. [phone]
[e-mail]
http://portal.ncdenr.org/web/wm/sw

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

From: Pieter Scheer [mailto:[e-mail]]  
Sent: Tuesday, May 16, 2017 10:43 AM 
To: Chao, Ming‐tai <[e-mail]> 
Cc: Buck, Rex <[e-mail]>; Sink, Steven <[e-mail]>; Scheer, Pieter 
<[e-mail]> 
Subject: Davidson County C&D Landfill (Permit No. 2906‐CDLF) Closure ‐ CQA Report 

Ming:

Please use the links below to access a transmittal letter and the CQA report for the closure of the C&D landfill unit.  Just 
let me know if you have any difficulties accessing the files.

Thanks.

Pieter

Pieter K. Scheer, P.E.
Vice President, Senior Engineer

SMITH + GARDNER

14 N. Boylan Avenue
Raleigh, NC 27603

P [phone]
F [phone]
C [phone]
www.smithgardnerinc.com
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