2601_AnnStreetMSWLFPhase3OperatingCapacityModification_DIN26572_20160803

5400 Glenwood Ave, Suite 400
Raleigh, North Carolina 27612
tel: [phone]
fax: [phone]

August 3, 2016

Mr. Ming-Tai Chao
Environmental Engineer
North Carolina Department of Environmental Quality
Division of Waste Management – Solid Waste Section
Raleigh Central Office
1646 Mail Service Center
Raleigh, North Carolina 27699-1646

Subject: Cumberland County, North Carolina
Subtitle D Landfill – Phase III Operating Capacity Modification
Permit No. 2601-MSWLF-1997

Dear Mr. Chao:
CDM Smith Inc. (CDM Smith), on behalf of Cumberland County (County), is requesting a modification of
the operating capacity of Phase III. In a letter dated May 10, 2016, the Solid Waste Section (SWS)
approved a slope of 3.5:1 (horizontal:vertical) along the eastern slope of the landfill and increased the
gross capacity of Phases I-III to 4,157,653 cubic yards (CY).
The County intends to place additional waste along the eastern slope so that a uniform slope of 3.5:1 is
achieved. A Civil 3D analysis estimates that approximately 57,000 cubic yards (CY) of additional material
will be placed along the eastern slope in order to provide a constant slope for construction of the final
cover system. Increasing the eastern slope to 3.5:1 increases the plateau area of Phase III by
approximately 90,000 CY. As stated in the Phase III Interim Closure Modification request dated April 22,
2016, once an elevation of 210 is reached the slope will transition back to 4:1 consistent with the landfill
final cover system presented in the Phase IV Permit to Construct Application.
The additional volume increases the currently permitted total gross capacity of 6,682,400 by 0.9%. This
represents the increase from the gross capacity approved by the SWS on May 10, 2016. A revised
grading plan and cross-section are attached and a revised version of Table 1-4 from the Phase IV Permit
to Construct Application is presented in Table 1.

Mr. Ming-Tai Chao
August 3, 2016
Page 2

Table 1. Subtitle D Landfill Phase Capacity and Operational Life
Phase Area
(acres)
Gross
Airspace
(cy)
Total Usable
Airspace
(cy)
Operating
Life
(years)
Remaining I-III (Current) 42.0 4,304,653 4,236,891 2.1
IV (Future) 13.3 928,609 861,979 5.0
V (Future) 01 928,609 861,979 5.0
VI (Future) 01 577,529 510,899 2.8
Total 55.3 6,739,400 6,471,748 14.9
Notes:
Gross Airspace – Volume of airspace from the top of the landfill base liner system through the top of the final
cover system.
Total Usable Airspace – Volume of airspace for MSW and daily cover and/or alternate daily cover material.
Does not include intermediate or final cover material.
1 – Vertical expansion
Please contact me at [phone] should you have any questions or if there is anything I can do to
help facilitate the approval of this request.
Sincerely,

Aaron M. Weispfenning, P.E.
CDM Smith Inc.

cc: Jeffery Brown, Cumberland County
Martin Sanford, CDM Smith
Camp Dresser McKee & Smith
CUMBERLAND COUNTY
NORTH CAROLINA
ANN STREET SUBTITLE D AND C&D
LANDFILLS
FIGURE
2016 SURVEY AND MODIFIED
INTERMEDIATE CLOSURE 1-1
PLAN REPRESENTS PERMITTED
CONTOURS RAISED TO EL. 215 AND
PROPOSED SLOPE MODIFICATION N
Camp Dresser McKee & Smith
CUMBERLAND COUNTY
NORTH CAROLINA
ANN STREET SUBTITLE D LANDFILL
FIGURE
MODIFIED INTERMEDIATE
CLOSURE SECTION
1-2
SECTION 1
HORIZONTAL SCALE 1"=80'
VERTICAL SCALE 1"=20'
1
Chao, Ming-tai
From:Weispfenning, Aaron <[e-mail]>
Sent:Wednesday, August 03, 2016 9:23 AM
To:Chao, Ming-tai
Cc:Sanford, Martin; Jim Blackwell; '[e-mail]'
Subject:Cumberland County Ann Street Landfill Capacity Modification
Attachments:August 2016 Phase III Operating Capacity Modification.pdf
Follow Up Flag:Flag for follow up
Flag Status:Flagged
Ming, 

Attached is a letter requesting an adjustment to the capacity of the Ann Street Landfill. The County intends to start 
placing additional waste on the eastern slope at the approved slope of 3.5:1 by the end of the week in order to achieve a 
uniform slope. Please let me know if there any issues. 

Thanks, 
Aaron 

Aaron M. Weispfenning, P.E. | Engineer | CDM Smith | 5400 Glenwood Avenue, Suite 400 Raleigh, NC 27612 | T: 919‐325‐3532 | F: 919‐781‐5730 
|  www.cdmsmith.com