9404_WashingtonCoCDLF_Comment_LOSPermitApp_DIN27645_20170418

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Chao, Ming-tai
From:Chao, Ming-tai
Sent:Tuesday, April 18, 2017 3:52 PM
To:Pieter Scheer ([e-mail])
Cc:Ritter, Christine
Subject:Comments on Washington County CDLF Permit Application, 94-04
Hi
Pieter: DI
N 27645

The Solid Waste Section (SWS) completed a review of the engineering portions of the life-of -site Permit
Application (DIN 27205) for Washington County C&DLF, Permit # 94-04. The SWS hydrogeologist is
reviewing the environmental media monitoring plans for the facility, and she or he may issue a separate
comment letter, if any.

Below are comments based on this review:
General
1. The discrepancy of the side slope of the landfill final cover system exists throughout the permit
application. According to slope stability analysis, the approved side slope is four (horizontal) to one
(vertical). Please provide the consistent value of the side slope in the permit application.

Attachment B - Facility & Engineering Plan
2. (Section 3.1) The Drawing No. S3 shows the 4H to 1V side slope of the proposed final cover
system. Please correct the typos.

3. (Section 6.2) What is the top deck slope? Slopes of 5 to 10% are proposed in this section but slopes of 5
to 8% are stated in Section 1.2 of the Closure Plan. The proposed slope should be consistent with the
results concluded from the Final Cover Veneer Stability Evaluation in Appendix A.

Attachment C – Technical Specifications
4. (Section 02222) The specification should include the following requirements because some portions of
the landfill base at Phase 3 area will be constructed by excavation according to the data in the summary
table of Earth Quality in Appendix A of the Facility & Engineering Plan:
i. To achieve the vertical separation requirements of the landfill base according to Rule 15A
NCAC 13B .0540(2)(b).
ii. The as-built survey requirements to document the completion of the landfill base.

5. (Section 02223) The specification should include the following requirements because some portions of
the landfill base at Phase 3 area will be constructed by backfilling selected fill material according to the
data in the summary table of Earth Quality in Appendix A of the Facility & Engineering Plan:
i. To achieve the vertical separation requirements of the landfill base according to Rule 15A
NCAC 13B .0540(2)(b).
ii. To be consistent with the specifications stated in the Section 3.0 of the CQA Manual, the
Contractor should submit the soil testing results of the selected backfill material from a borrow
source (s) to CQA Engineer for a review and approval prior to shipping the material to the
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project site. The soil testing may include soil gradation, Atterberg limits, compaction curves
according to Standard Proctor testing, etc.
iii. (Paragraph D.5.) The landfill base subgrade preparation and confirmation should include the
requirements stated in Rule 15A NCAC 13B .0540(5).
iv. The as-built survey requirements to document the completion of the landfill base.

6. (Section 02250) The maximum lift thickness of a compacted soil liner should be six (6) inches. Please
revise the data in Table 2.

7. (Sections 02240 & 02270) The Paragraphs A & B of Section 02270 shall reference the material
requirements of Geotextile specified in Section 02240. The specified mass per united area of the
Geotextile in Section 02270 must be added to Table 1 in Section 02240.

8. (Section 02250) Each compacted/in-place lift of the proposed soil liner should have the thickness of six
(6) inches or less. Please correct the specified thickness in the Table 2.

Attachment D – Construction Quality Assurance Manual
9. (Section 3.3.1) The Section 3.2 referenced in the item B of this sub-section is likely a typo.

Attachment E - Operations Manual
10. The Manual may need add the reference of Appendix C – Mobile Home Destruction Plan to Section 1.0
or Section 2.4.3.

11. (Section 2.8) The last sentence of the first paragraph states that “Thus, MSW will not be
processed.” This statement creates confusion because the C&DLF unit/facility shall not receive any
MSW for disposal.

12. The Manual shall discuss the control of dust resulting from waste operations according to Rule 15A
NCAC 13B .0542(j)(4).

Attachment F - Closure & Post-closure Plan
13. (Section 1.3) Please confirm the side slope of the proposed final cover system.

Please contact me if you have any questions on the above-mentioned comments. Thanks and have a wonderful
evening.

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
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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: Chao, Ming-tai
Sent: Friday, March 24, 2017 10:26 AM
To: Pieter Scheer ([e-mail]) <[e-mail]>
Cc: Joan Smyth ([e-mail]) <[e-mail]>
Subject: Washington County CDLF Permit Application, 94-04

Hi Pieter:

Since Pat Backus is retiring in the end of month, I will be the engineer to review the Life-of-Site Permit Application for
Washington County CDLF, Permit No. 94-04 which was received by the Solid Waste Section on 01/03/2017 and logged in
the document tracking system with a DIN 27205. I will review the document shortly. Please contact me if you have any
question of the permit reviewing processes. Have a wonderful weekend.

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

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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