1107_BuncombeCo_MSWLF_FacilityPlanUpdate_DIN27850_20170530

3920 Arkwright Road, Suite 101 | Macon, Georgia | Phone: [phone] | Fax: [phone]

2017 FACILITY PLAN MODIFICATION

BUNCOMBE COUNTY SOLID WASTE MANAGEMENT FACILITY
SUBTITLE D LANDFILL

FOR

BUNCOMBE COUNTY, NORTH CAROLINA

MAY 2017

NC Corp. License # C-0813

2017 Facility Plan Modification
Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

TABLE OF CONTENTS
SECTION:

A. Narrative
B. Correspondence Related to Permitting
C. Facility Drawings
D. Appendix
1. C&D Landfill Facility Report
2. Engineering Plan Updates:
I. Introduction
II. Fabric Puncture Protection of Existing Geomembrane
III Burial Design of Leachate Collection Pipe
IV. Slope Stability Evaluation

3. Operation Plan Updates
4. Closure and Post-Closure Plan Updates

2017 Facility Plan Modification
Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

A. NARRATIVE

2017 Facility Plan Modification
Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

TABLE OF CONTENTS
Section Page
I. INTRODUCTION 1
II. .1617 APPLICATION REQUIREMENTS FOR MSWLF FACILITIES 2
III. .1619 FACILITY PLAN 4

 Supporting Data & Calculations 14
IV. REPORT ON SERVICE AREAS, POPULATION SERVED, WASTE RECEIVED, AND EQUIPMENT 17
V. CONCEPTUAL DESIGN PLAN 18
VI. .1680 LEACHATE STORAGE REQUIREMENTS 21

2017 Facility Plan Modification
Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

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I. INTRODUCTION
The Buncombe County Solid Waste Management Facility manages solid waste in the state of
North Carolina. This application has been prepared to modify the final grades within existing
constructed cells 1-6. Previous Permit Applications (prepared by others) accomplished a similar
modification, however, that modification was limited to cells 7-10. This modified Facility Plan is
being provided to extend a similar increase in final sideslope inclination from 4H:1V, as originally
permitted, to a grade of 3H:1V within all remaining MSW cells at this facility (cells 1-6).
In accordance with § 130A-294(b)(b1) of the North Carolina General Statutes, a substantial
amendment is defined as:
A. An increase of ten percent (10%) or more in:
1. The population of the geographic area to be served by the sanitary landfill;
2. The quantity of solid waste to be disposed of in the sanitary landfill; or
3. The geographic area to be served by the sanitary landfill.
B. A change in the categories of solid waste to be disposed of in the sanitary landfill or any
other change to the application for a permit or to the permit for a sanitary landfill that
the Commission or the Department determines to be substantial.
Based on the above definition, this modified Facility Plan is not a substantial amendment. While
the proposed modifications do increase the quantity of solid waste to be disposed of in the
sanitary landfill, this increase is less than 10% of what is currently permitted.
This facility continues to be developed with a composite liner system, and with a leachate
collection system meeting the requirements of Subtitle D and the North Carolina Administrative
Code Title 15A Chapter 13 Solid Waste Management Rules.
The facility continues to be developed on land owned by Buncombe County, North Carolina. The
general area around the facility is rural residential and wooded. Other land uses in the general
area of the facility include pasture and densely wooded tracts.
This application does not attempt to expand or modify the horizontal extents of the permitted
landfill boundary or the waste disposal footprint area. Therefore, the following facility
information has not been included in this document, since it is assumed that these items have
been previously reviewed and approved by NC DEQ. These sections include:
 .1618 Site Study for MSWLF Facilities: Regional Characterization Study
 .1618 Site Study for MSWLF Facilities: Local Characterization Study
 .1622 Location Restrictions for MSWLF Facility Siting
 .1623 Geologic and Hydrogeologic Investigations for MSWLF Facilities

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May 2017 HHNT Project No. 1401-010-01

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II. .1617 APPLICATION R EQUIREMENTS FOR MSWLF FACILITIES
(e) Permit renewal. A complete application for a permit to construct a lateral expansion or
a new MSWLF unit shall contain the following:
(1) A Facility Plan that describes comprehensive development of the MSWLF facility
prepared in accordance with Rule .1619 of this Section;
A Facility Plan prepared in accordance with Rule .1619 of this Section is
included in this document.
(2) An Engineering Plan that is prepared for the initial phase of landfill development
prepared in accordance with Rule .1620 of this Section;
An Engineering Plan prepared for Phase IV (Cell 7) of landfill development was
prepared in accordance with Rule .1620 of this section, and has been approved
by NC DEQ.
An Engineering Plan prepared for Phase V (Cells 9-10) of landfill development
will be prepared in accordance with Rule .1620 of this Section and will be
included in a subsequent Permit to Construct Application document, at the
appropriate time.
(3) A Construction Quality Assurance Plan prepared in accordance with Rule .1621
of this Section;
A Construction Quality Assurance (CQA) Plan prepared in accordance with Rule
.1621 of this section was included with the Phase IV (Cell 7) Permit to
Construct application, and has been approved by NC DEQ. An updated CQA
Plan will be included as subsequent Permit to Construct applications are filed
for future phases.
(4) An Operation Plan prepared in accordance with Rule .1625 of this Section;
An Operation Plan prepared in accordance with Rule .1625 of this Section was
included with the Phase IV (Cell 7) Permit to Construct application and has
been approved by NC DEQ. An updated Operation Plan will be included as
subsequent Permit to Construct applications are filed for future phases.
In addition, Operational Phasing Drawings demonstrating the proposed waste
filling sequence within Cells 1-6 will be provided under separate cover, once
completed.
(5) A Closure and Post Closure Plan prepared in accordance with Rule .1629 of this
Section; and
A Closure and Post Closure Plan prepared in accordance with Rule .1629 of this
Section was included with the Phase IV (Cell 7) Permit to Construct application,
and has been approved by the NC DEQ.
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May 2017 HHNT Project No. 1401-010-01

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(6) A Water Quality Monitoring Plan prepared as set forth in Paragraph (b) of Rule
.1623.
The facility maintains an existing Water Quality Monitoring Plan which has
already been approved by NC DEQ. This existing plan will be updated and
revised in conjunction with subsequent phases being developed. A Water
Quality Monitoring Plan prepared as set forth in Paragraph (b) of Rule .1623
will be submitted as subsequent Permit to Construct applications are filed for
future phases.

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Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

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III. .1619 FACILITY PLAN
(a) Purpose. As required under Rule .1617 of this Section, a permit applicant shall prepare a
facility plan which meets the requirements of this Rule.

(b) Scope.
(1) The facility plan defines comprehensive development of the property proposed
for permit or described in the permit of an existing facility. The plan includes a
set of drawings and a report which present the long-term, general design
concepts related to construction, operation, and closure of the MSWLF unit(s),
including leachate management. The scope of the plan spans the active life of
the MSWLF unit(s). Additional solid waste management facilities located at the
MSWLF facility shall be identified in the plan and shall meet the requirements of
this Subchapter. The facility plan defines the waste stream proposed for
management at the MSWLF facility. If different types of landfill units or non-
disposal facilities are included in the facility design, the plan must describe
general waste acceptance procedures.
(2) The areal limits of the MSWLF unit(s), total capacity of the MSWLF unit(s), and
the proposed waste stream shall be consistent with the Section's approval set
forth:
(A) In accordance with Rule .1618 (a)(1) of this Section for a new facility: or,
(B) In accordance with the current permit for an existing facility applying for
permit renewal.

(c) Use of Terms. The terminology used in describing areas of the landfill unit shall be
defined in the facility plan and shall be used consistently throughout a permit
application. The Section recommends the use of the following terms:

(1) A "phase" is an area constructed with a base liner system that provides no more
than approximately five years of operating capacity.

(2) A "cell" is a subdivision of a phase which describes modular or partial
construction.

(3) A "subcell" is a subdivision of a cell which describes leachate and stormwater
management for active or inactive areas of the constructed MSWLF.

(d) Facility Drawings. The facility plan shall include the following drawings:

(1) Site Development. The two drawings which plot site development shall be
prepared on a topographic map representative of existing site conditions; the
map shall locate the physical features referenced in Rule .1622 of this Section and
shall incorporate a survey locating all property boundaries for the proposed
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Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

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landfill facility certified by an individual licensed to practice land surveying in the
State of North Carolina.

(A) Landfill units and leachate facilities. This drawing shall delineate the
aerial limits of all landfill units and leachate facilities and incorporate
the buffer requirements set forth in Subparagraph (b)(3) of Rule .1624.
(B) All facilities. These drawings shall locate all solid waste management
facilities and facility infrastructure, including landfill units and leachate
facilities.

Facility Drawings and this Facility Plan show each item required by this
Rule. These drawings are found in Section C of this permit application
document.

(2) Landfill Construction. All on-site grading activities related to the construction
and operation of the MSWLF unit(s) shall be illustrated in facility drawings which:

(A) Delineate the limits of grading, including borrow and stockpile areas;
(B) Define phases of development which do not exceed approximately five
years of operating capacity;
(C) Propose base grades for the MSWLF unit(s);
(D) Delineate the location of access roads, sedimentation basins, leachate
pipeline and storage or treatment facilities and other structures related
to the operation of the MSWLF unit; and
(E) Propose final contours for the MSWLF unit(s) and facility features for
closure.

The Facility Drawings show each item required by the Rules.

(3) Landfill Operation. The following information related to the long-term operation
of the MSWLF units shall be included in facility drawings;

(A) General grade and flow direction for the drainage layer component of
the leachate collection system;
(B) Size, location, and general grade for the leachate piping system,
including on-site pipelines to leachate management facilities;
(C) Proposed transitional contours for each phase of development, including
operational grades for existing phase(s) and construction grading for the
new phase; and
(D) If included in the design, storm water segregation features and details
for inactive landfill subcells.

The Facility Drawings show each item required by the Rules.

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May 2017 HHNT Project No. 1401-010-01

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(e) Facility Report. The facility plan shall include the following information:

The responses below have been provided in accordance with this rule for the MSW
(Subtitle D) Landfill only. A separate report has been prepared for the Construction &
Demolition (C&D) Landfill by others. A copy of the C&D Facility Report is provided in
the Appendix of this report.

(1) Waste stream. A discussion of the characteristics of the wastes received at the
facility and facility specific management plans shall incorporate:

(A) The types of waste specified for disposal;

This Subtitle D facility will accept municipal solid waste, consisting of
residential, commercial, and non-hazardous industrial waste, as well
as other non-hazardous waste types allowed by the Solid Waste
Regulations and as specified in the Permit to Operate. Prohibited
wastes will be excluded. C&D waste will be disposed in the separate
C&D Landfill.

The Operation Plan includes a Waste Screening Plan which will be used
in determining whether or not incoming waste may be accepted in the
Subtitle D and/or C&D facilities.

This facility does receive some wastes which are not landfilled. These
wastes include: wood and yard waste, white goods, batteries, motor
oil, tires, household hazardous waste (HHW), triple-rinsed pesticide
containers, and some recyclables.

(B) Average monthly disposal rates and estimated variance;

The average annual MSW disposal rate is expected to be ±120,000
tons, or (385 tons per day) assuming 312 operating days per year. This
waste rate is based on current records. Actual landfill disposal records
are summarized in the Table below:

MSW Disposal Rates

FY1 Amount Received
(tons)
Daily Rate (tons/day)
98-99 109,734 386
99-00 120,143 423
00-01 122,333 431
01-02 146,690 517
02-03 160,863 566
03-04 170,170 599
04-05 173,774 612
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May 2017 HHNT Project No. 1401-010-01

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05-06 122,034 430
06-07 117,216 413
07-08 143,994 507
08-09 129,551 456
09-10 113,497 400
10-11 116,876 412
11-12 109,317 385
12-13 107,469 378

(C) The area served by the facility;

The geographical area that may be served by the facility includes the
incorporated and unincorporated areas of Buncombe County only.
Buncombe County includes the incorporated municipalities of
Asheville, Biltmore Forest, Black Mountain, Montreat, Weaverville,
and Woodfin.

(D) Procedures for segregated management at different on-site facilities;
and

All waste screening and segregation procedures used by the
Buncombe County Solid Waste Management Facility staff are included
in the Operation Plan.

(E) Equipment requirements for operation of the MSWLF unit.

The facility will utilize the following equipment for the Subtitle D
Landfill:

Farm tractor with mower
Slope mower
Steel wheel compactors
Bulldozers
Excavator
Haul truck/Articulated Dump Truck
Pick-up truck
Skid Loader
Rubber Tired Loader
Track Loader
Motor Grader
Tub Grinder
Roll-off Tank
Fuel Truck

In addition to this basic equipment, other equipment will be utilized or
substituted on-site when necessary.
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May 2017 HHNT Project No. 1401-010-01

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(2) Landfill Capacity. An analysis of landfill capacity and soil resources shall be
performed.

(A) The data and assumptions used in the analysis shall be:
(i) Consistent with the facility drawings and disposal rates specified
in the facility plan; and
(ii) Representative of operational requirements and conditions.

Calculations shown in this section demonstrate that data and
assumptions used in the analysis are consistent with the facility
drawings and disposal rates in the facility plan; and that they
are representative of operational requirements and conditions.

(B) The conclusions shall provide accurate volumetric estimates of:
(i) Total operating capacity;

The total operating capacity of the facility is approximately
12,477,000 million cubic yards, based on the facility drawings.
The operating capacity includes soil for intermediate and daily
cover. This volume does not include soil for final capping.

Assuming a waste density of 1,560 lbs/cy, this capacity
equates to approximately 9,732,060 tons.

(ii) Operating capacity for each phase of development;

A preliminary estimate of the operating capacity of each phase is:

Total Operating Capacity ± 12,477,000 CY
Phase I (Cells 1-3) (approx.) ± 2,196,000 CY
Phase II (Cells 4-5) (approx.) ± 1,233,500 CY
Phase III (Cell 6) (approx.) ± 2,176,000 CY
Phase IV (Cell 7) (approx.) ± 1,273,500 CY
Phase V (Cells 9-10) (approx.) ± 1,483,500 CY
Phase VI (Cell 8) (approx.) ± 792,500 CY
Phase VII (Vertical Expansion) (approx.) ± 3,322,000 CY

Variations in waste volumes, waste density, and final design could
cause phases to last for longer or shorter periods. Final designs will
adjust for this variation. In general, phases should last about 5 years
each.

The permanent landfill sideslopes for all Phases will be 3H:1V
(horizontal:vertical). The operating capacities listed above reflect the
3H:1V sideslopes.
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May 2017 HHNT Project No. 1401-010-01

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(iii) In-Place ratio of waste to soil;

Based on data provided by the County, a waste-to-soil ratio of
4:1 has been assumed. Therefore, it is projected that daily and
intermediate soil cover will be equal to about 1,771,000 cubic
yards or about 20% of the total remaining airspace volume, and
final cover will be equal to about 319,000 cubic yards. This is a
conservative estimate since the use of Posi-shell as an
approved alternate daily cover material should reduce the sites
dependence on soil for daily cover.

(iv) Available soil resources from on-site or specific off-site sources;

Available cover soil and soil for other purposes (i.e. capping,
structural fill) is estimated to be ± 1,398,000 cubic yards, based
on information obtained from the Cell 7 PTC Permit
Application. Adequate material is not currently located on-site,
and therefore, off-site soils may be utilized from time to time.
In addition, Buncombe County owns adjacent lands which can
be permitted and utilized for borrow material.

(v) Required quantities of soil for landfill construction, operation,
and closure; and

The estimated soil requirements for future landfilling activities
are provided in the Supporting Data and Calculations.
Approximately 2,185,900 cubic yards of soil will be required for
landfill construction, operation and closure.
(vi) The estimated operating life of all MSWLF units in years.

The remaining landfill life is estimated to be 46 years, based on
projected waste streams. The supporting calculations are
based on a waste disposal rate of 385 TPD. Some fluctuations
in waste stream and density are anticipated which may impact
the operating life of the facility. Each phase will provide a
minimum of five years capacity. Phase sizes may be changed
during detailed design to match cell capacity to a minimum five
year life.

(3) Containment and environmental control systems. A general description of the
systems designed for proper landfill operation, system components, and
corresponding functions shall be provided.

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Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

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This landfill facility is designed as a contained landfill system. During landfill
development, cell filling, and closure, a liner and leachate collection system will
be utilized to assure that all precipitation contacting waste will be collected
and managed as leachate. Leachate collected on the liner will be pumped to a
lined leachate storage pond. This leachate pond is equipped with a liner
system. The in-cell leachate collection system is designed to collect and
remove leachate from the cell, while assuring leachate head on the liner will
not exceed 12 inches.

The base liner system will be a composite system consisting of a compacted,
smooth subgrade, an 18 inch thick soil liner with k ≤ 1 x 10-5 cm/sec plus a
reinforced geosynthetic clay liner (GCL) overlain by a 60 mil textured HDPE
flexible membrane liner (FML). Quality Control and Quality Assurance
procedures will be utilized to demonstrate liner construction quality. The base
grades will be designed to maintain a minimum post-settlement slope of 2%
and a minimum post-settlement vertical separation of 4’ above seasonal high
ground water table and bedrock.

The leachate collection and removal system will utilize a permeable media
above the liner, with a piping network, to assure complete removal of leachate.
All components will be sized to adequately manage flows and surges. Ten inch
diameter perforated HDPE collection pipe will be installed in areas of
concentrated flow to efficiently route leachate to the sump. Leachate in the
collection pipes will flow by gravity to sump areas where a submersible pump
will be installed to remove leachate from the cells. Once leachate is removed
from the liner, it will be transferred by force main to the lined pond.

Wall crushing and wall buckling calculations for the leachate pipes in Cells 1-6
have been evaluated to ensure that acceptable factors of safety are
maintained, with the increased height of waste filling. Based on those
calculations, the leachate pipes in those existing cells will maintain the
appropriate factors of safety. This demonstration has been included in the
Appendix of this report.
A final cover system will be installed after waste filling is complete to minimize
infiltration of stormwater and control landfill gas. The composition of the cap
system will be a geomembrane overlain by an 18-inch layer of protective soil
and 6-inch erosion soil layer with sufficient organic content to sustain
vegetative growth. The closure cap will have a maximum grade of 3 to 1
(horizontal to vertical) for Cells 1 through 10. A minimum slope of five percent
will be used for the final plateau.
Stormwater runoff from the landfill will be collected and routed to a series of
sedimentation ponds to remove suspended solids prior to discharge.
Intermediate cover slopes will be maintained with a good stand of grass to
limit erosion and repairs will be made in a timely manner.
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Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

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An active gas collection system consisting of vertical and horizontal wells is
used to collect landfill gas. The collected gas in combusted onsite in a
generator set and a flare.
(4) Leachate Management. An analysis of the leachate management requirements
and plans for the MSWLF facility shall incorporate the information required
under this Subparagraph.
(A) The performance of and design concepts for the leachate collection
system within active areas of the MSWLF unit and any storm water
segregation included in the engineering design shall be described.

The cells are designed with stormwater rain flaps to minimize the
precipitation contact with the waste. This procedure minimizes
production of leachate within the landfill.

In addition, tarps may be used to help segregate clean water from
waste. Any stormwater that comes in contact with waste will be
considered leachate and must be handled as such.

The leachate collection system is designed with pipes and filter media
to promote leachate drainage, and to assure sustained leachate head
on the liner does not exceed 12 inches. Historically, this site has
utilized a 24” thick stone or other soil/gravel media with a hydraulic
conductivity of 1.0 cm/sec as the protective cover layer. A geotextile
cushion fabric will be used under the stone drainage layer to protect
the FML.

(B) Normal operating conditions. Normal operating conditions shall be
defined and must consider:

(i) Average monthly values for leachate generation
representative of the landfill's environment and operation
using:
(I) empirically derived estimates; or
Leachate volumes have been previously estimated
based on the U.S. Army Corp of Engineers HELP Model
(Hydraulic Evaluation of Landfill Performance). The
HELP Model calculations are performed and provided
in each Engineering Plan/Permit to Construct
application for normal operating conditions using
weather and other empirical data from local areas.
(II) for landfill expansions, actual leachate generation
data from the existing landfill.
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Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

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Since this is an existing landfill, estimates of actual
volume will be utilized for determining leachate
volumes in subsequent permit applications.
(ii) Surge volumes generated by storm events.
Surge volumes are typically estimated by inserting the 24-hour,
25-year storm event into the HELP Model manually. Utilizing
this technique a maximum daily peak volume of leachate in
(gallons per acre per day) at this facility (including storm
events) can be estimated.
(C) Leachate management system. A description of the leachate
management system components and their engineered function shall be
provided, including:

(i) Leachate pipeline operating capacity;
All leachate collection piping has been designed based on the
peak daily leachate generation rate for the worst case
condition. Detailed Design Calculations have been provided in
previously submitted Engineering Reports for existing cells and
will be provided in future Engineering Reports for all cells
remaining to be constructed.
(ii) Capacity of the storage and if applicable, the treatment
facilities;
The leachate storage capacity is 1,000,000 gallons, which
includes one lined leachate storage pond. Currently, there are
no on-site treatment facilities. Future pretreatment or
treatment facilities are possible and may be considered in
future permit applications. Design of any future treatment
facilities will be completed when that treatment is required.
(iii) Final disposal plans and applicable discharge limits, including
documented prior approval of the waste water treatment
plant which may be designated in the plan.
Leachate will be managed through recirculation back into the
landfill, or transportation off-site to either commercial
treatment facilities, or publicly owned treatment works
(POTW). Each receiving treatment facility will establish
pretreatment standards and applicable discharge limits. The
facility currently hauls leachate to the Metropolitan Sewerage
District (MSD) Wastewater Treatment Facility.
(D) A contingency plan shall be prepared for storm surges or other
considerations exceeding design parameters for the storage or
treatment facilities.
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Buncombe County Solid Waste Management Facility Buncombe County, NC
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The facility will be designed and developed with a system for
segregating cells with waste from cells which have not yet received
waste. Those cells which have not yet received waste will be drained
(gravity or pumped) to the storm drainage system which is capable of
handling the 25-year storm event. Subcells containing waste should be
limited to about 2 acres. This limitation is sufficient for the
management of the 25-year storm event in the leachate management
system. Storms with greater duration, or conditions causing surges
greater than projected may be stored in the lined cell for periods not-
to-exceed 72 hours.

In addition, this facility is approved for leachate recirculation. When
recirculation is not possible, leachate will be hauled to the MSD
Wastewater Treatment Facility or stored in the 1,000,000 gallon lined
leachate storage pond. If necessary, pump and haul to other treatment
plants may be utilized.
(5) Special engineering features.

This facility utilizes engineering features shown on the facility drawings. Also,
as detail design of the individual phases is completed, other engineering
features may be added which enhance the facility operations.

Examples of current special engineering features include automated pumping
stations to minimize storage time for leachate in the landfill cells, and leachate
recirculation into the waste mass. This recirculation effort is expected to
accelerate decomposition of the MSW thereby increasing landfill capacity and
gas generation for the gas-to-energy facility.
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Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

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SUPPORTING DATA & CALCULATIONS

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Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

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LANDFILL CAPACITY

ASSUMPTIONS:
1. Waste Stream 385 tons/day
2. Waste Density 0.78 tons/cy (1,560 lbs/c.y.)
3. Approximate Gross Capacity of Site 12,796,000 c.y.
4. 3H:IV final sideslopes for Cells 1-10 including the vertical expansion.

Part One - Five Year Requirements

312 operating days/year x 385 tpd x (2,000 lbs/ton / 1,560 lbs/c.y.)
x 5 years ÷ 0.80 (cover) = about 962,500 c.y.

 Use 963,000 c.y. for 5 years capacity required or roughly 192,600 c.y. per year.

Part Two - Remaining Facility Life

Site Capacity = 12,796,000 c.y.
Soil Cap = 319,000 c.y.
Volume Consumed (as of May 2016) = 3,621,639 c.y.
Remaining Capacity = 8,855,361 c.y.

8,855,361 c.y. ÷ 192,600 c.y./year = ±46 years

NOTE: These calculations are based on the assumed waste disposal numbers listed above. Some
fluctuations in waste stream and density are anticipated which could impact remaining site life.

SOIL REQUIREMENTS

Part One - Structural Fill Requirements

Clay Liner (minus) 95,900 c.y.
Potential Borrow Soil on Site (plus) 1,398,000 c.y.
Net Soil Available 1,302,100 c.y.

Part Two - Cover Requirements
Assume 5:1 waste to soil ratio for daily and intermediate cover
Total Volume of Waste and Cover = ±8,855,361 c.y.
Daily & Intermediate Cover = 8,855,361 c.y. x (20%) = ± 1,771,000 c.y.
Final Cover ±319,000 c.y.
Soil Required = ±2,090,000 c.y.

TOTAL SOIL REQUIREMENTS = 1,302,100 c.y. (available) – 2,090,000 c.y. (needed) = 787,900 c.y.
(deficit)
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 The site has a soil deficit of 787,900 c.y. This is a rough estimate based on
information contained in the Cell 7 PTC Permit Application. We understand that
the County has purchased an adjacent property that may be considered for
future borrow material.

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May 2017 HHNT Project No. 1401-010-01

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IV. REPORT ON SERVICE AREAS, POPULATION SERVED, WASTE
RECEIVED, AND EQUIPMENT
(1) The geographical area that may be served by the facility is the incorporated and
unincorporated areas of Buncombe County:

NORTH CAROLINA
COUNTY
2015
POPULATION
(ESTIMATED)
BUNCOMBE 254,836

All population information contained in this report was obtained from the Federal
State Cooperative Program as found on the Demographics Unit web site
(https://ncosbm.s3.amazonaws.com/s3fs-public/demog/countygrowth_cert_2015.html),
or the U.S. Census Bureau web site
(http://factfinder.census.gov/faces/tableservices/jsf/pages/productview.xhtml?src=bkm
k).
(2) The service area and associated population producing waste corresponds to item (1)
above. The waste from the approved service area is principally municipal solid waste
with some fraction of non-hazardous industrial waste. Other waste from Buncombe
County may also be accepted for disposal.

(3) The following lists the major equipment that will be used to operate the site. It should
be noted that there will be periods where additional equipment may be required.
During these periods, equipment will either be brought in from other County facilities or
rented for the activity that requires that equipment.

Farm tractor
Slope Mower
Steel wheel compactors
Bulldozers
Excavator
Haul truck/Articulated Dump Truck
Pick-up truck
Skid Loader
Rubber Tired Loader
Track Loader
Motor Grader
Tub Grinder
Roll-off Truck
Fuel Truck
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V. CONCEPTUAL DESIGN PLAN
The project concept utilizes the North Carolina Rules Section .1600. The North Carolina Rules
serve as the principal basis of design. The facility will be developed with an approved
alternative liner system utilizing a geosynthetic clay liner over an 18" thick layer of k ≤1x10-5
cm/sec low permeability soil liner, in lieu of a 24" thick layer of k ≤1x10-7 cm/sec clay liner.
These components will be in intimate contact with one another and together, will form the
composite liner.
A Leachate Collection System (LCS) will be installed on top of the composite liner. This LCS will
consist of a network of gravity drain perforated pipes in the low points of the liner and a
drainage media over the remainder of liner bottom surface. This drainage media will be
designed utilizing the Hydraulic Evaluation of Landfill Performance (HELP) Model to promote
drainage from the liner to the LCS drain pipes. The drainage media will prevent the depth of
leachate on the composite liner from reaching any depths greater than 12". Historically, this
site has utilized a 24” thick stone or other soil/gravel media with a hydraulic conductivity of 1.0
cm/sec.
The landfill leachate collection system design will incorporate methods to divert the storm
water from the liner surface in a manner to prevent excess leachate production. These
methods will be designed so that any precipitation contacting the waste will be treated as
leachate, and any precipitation which never contacts the waste will be treated as stormwater.
The LCS will utilize individual submersible sideslope riser pumps in the sumps. These will be
directed by force main to a lined storage pond located on-site prior to ultimate transport to a
wastewater treatment plant (WWTP) or Publicly Owned Treatment Works (POTW). Leachate
will primarily be hauled to the Metropolitan Sewerage District (MSD) Wastewater Treatment
Facility for treatment and disposal. Alternate facilities, including other WWTP/POTW facilities
may be utilized from time to time as contingency locations. The leachate pond was designed
to accommodate the volume of leachate necessary to provide adequate equalization and
retention prior to further transport to a WWTP/ POTW for ultimate treatment. The MSD
WWTP has accepted leachate from this facility for treatment. Additionally, leachate may be
treated by recirculation into the waste mass in all cells, as part of the ongoing
research/demonstration project.
The landfill will utilize a fill method which will provide for compaction of the waste to its
smallest practicable volume. The waste will be covered daily with either six inches of soil or an
approved alternative daily cover. Intermediate lifts in the landfill waste mass will be covered
with twelve inches of soil. The landfill facility will then be capped with a Subtitle D type cap
system or alternative cap system which restricts precipitation from infiltrating into the waste
mass.
The landfill will be designed to maximize the potential waste fill volume of the site. For
conceptual purposes, the cover soil requirements were estimated at a soil to waste ratio of
approximately one part soil to four parts waste.
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The landfill will have a groundwater monitoring system for detection of potential
contamination. This system will be based on the site hydrogeology and the facility design. As
future cells are constructed, additional downgradient wells will be installed as needed to
adequately detect potential contamination. Future groundwater wells will be installed in
accordance with the well phasing schedule found in subsequent Construction Permit
Applications. The landfill will incorporate drainage devices to assure that there is no run-on
surface water and that run-off surface water will be handled through retention / sediment
control basins.
The landfill has a landfill gas collection system to effectively manage the gas generated at the
facility. In addition, the site maintains a gas-to-energy plant that is located at the facility.
The landfill facility is sited so that there are 300 foot buffers between the waste and any
property line, 50 feet between any waste and streams, a vertical separation between the
waste and groundwater of at least four feet, and a vertical separation between the waste and
rock of at least four feet.
Soil for landfill cover will be excavated on-site from the facility or from adjacent lands owned
by the County.

The engineering design will be completed to accomplish the following:

1. Protect the water and land resources of the site and adjacent lands.
2. Provide a landfill system with liners and a leachate collection system.
3. Maximize the landfill life.
4. Create an aesthetically pleasing site which is efficient to operate.
5. Properly manage leachate to prevent any environmental damage.
6. Control access to the site.
A set of Facility Design Drawings are included with this application:
Sheet No. Title
- Title Sheet
SD-1 Site Development Existing Conditions
SD-1A Site Development Existing Conditions – Enlarged View
SD-2 Site Development C&D Landfill
SD-3 Site Development Subtitle D Landfill
SD-4 Site Development Landfill Gas-to-Energy (LFGTE) Facility
LC-1 Landfill Construction Subtitle D Landfill Base Grades
LC-2 Landfill Construction Subtitle D Landfill Leachate Collection
LC-3 Landfill Construction C&D Landfill Base Grades
LO-1 Landfill Operation Transition Contours Subtitle D Landfill
- Phase I-III Closure Grades Phase IV Base Grades
LO-2 Landfill Operation Transition Contours Subtitle D Landfill
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- Phase IV Closure Grades Phase V Base Grades
LO-3 Landfill Operation Transition Contours Subtitle D Landfill
- Phase V Closure Grades Phase VI Base Grades
LO-4 Landfill Operation Transition Contours Subtitle D Landfill
- Phase VI Closure Grades Phase VII Base Grades (Vertical
Expansion)
LO-5 Landfill Operation Transition Contours Subtitle D Landfill
- Phase VII Closure Grades (Vertical Expansion)
LO-5A Cross Section A
LO-5B Cross Section B
LO-6 Landfill Operation Transition Contours C&D Landfill
- Phase 5 Closure Phase 6 Base Grades
LO-7 Landfill Operation Transition Contours C&D Landfill
- Phase 6 Closure Phase 7 Base Grades
LO-8 Landfill Operation Transition Contours C&D Landfill
- Phase 7 Closure Phase 8 Base Grades
LO-9 Landfill Operation Transition Contours C&D Landfill
- Phase 8 Closure
The Buncombe County Solid Waste Management Facility site has been evaluated in detail by
other firms and consultants a part of the earlier permitting process. These investigations
included at a minimum, those elements identified in the 15 NCAC 13B .1600 rules sections.
In summary, these investigations considered cultural resources, regulatory, hydrogeological,
geotechnical, topographical, conceptual design, regional, local, environmental, and numerous
other issues. Based on the investigations and evaluations by these professionals, the
Buncombe County Solid Waste Management Facility site has been previously determined to
be suitable for its intended use.

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VI. .1680 LEACHATE STORAGE REQUIREMENTS
(a) Applicability.
(1) Construction of leachate storage tanks and surface impoundments located at
solid waste landfill facilities after October 9, 1993 shall meet the requirements
set forth in this Rule.
The on-site lined leachate storage pond was designed to meet all the
provisions of this rule.
(2) Liquid treatment and disposal at a solid waste landfill facility is subject to the
requirements of this Subchapter.
This rule will be complied with.
(3) Operation and closure of all leachate storage tanks and surface impoundments
shall meet the requirements of this Rule.
This rule will be complied with.
(b) Application requirements. An application for a permit to construct a landfill facility which
includes leachate storage facilities shall contain the following:
(1) A description of the liquid to be stored;
(2) The estimated volume of liquid generated and a proposed recordkeeping system
to record actual quantities stored;
(3) A schedule for liquid removal;
(4) A description of the final treatment and disposal of the liquid stored;
(5) A description of the liquid storage facility design;
(6) A contingency plan for managing unexpected surges in liquid quantities; and
(7) A closure plan prepared in accordance with Paragraph (f) of this Rule.
Should additional leachate storage ponds, or tanks be constructed at this
facility, they will fully comply with this rule.
(c) Aboveground or onground tank requirements.
(1) Tanks may be constructed of concrete, steel, or other material approved by the
Section. Tanks shall be supported on a well drained stable foundation which
prevents movement, rolling, or settling of the tank.
(A) The exterior surfaces of all aboveground and onground steel storage
tanks shall be protected by a primer coat, a bond coat and two or more
final coats of paint or have at least an equivalent surface coating system
designed to prevent corrosion and deterioration.
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(B) The interior of all aboveground and onground tanks shall consist of a
material, or shall be lined with a material, resistant to the liquid being
stored.
Should storage tanks be constructed at this facility, these conditions
will be complied with.
(2) All aboveground and onground tanks shall have a secondary containment
system which may consist of dikes, liners, pads, ponds, impoundments, curbs,
ditches, sumps, or other systems capable of containing the liquid stored.
(A) The design volume for the secondary containment system shall be 110
percent of the volume of either the largest tank within the containment
system or the total volume of all interconnected tanks, whichever is
greater.
(B) The secondary containment system shall be constructed of a material
compatible with the liquid being stored.
Should storage tanks be constructed at this facility, these conditions
will be complied with.
(3) A system shall be designed to contain and remove storm water from the
secondary containment area. Provisions shall be included for the removal of any
accumulated precipitation and be initiated within 24 hours or when 10 percent
of the storage capacity is reached, whichever occurs first. Disposal shall be in
compliance with all applicable federal and State regulations.
Not applicable at this facility.
(4) All aboveground and onground tanks shall be equipped with an overfill
prevention system which may include, but not be limited to: level sensors and
gauges, high level alarms or automatic shutoff controls. The overfill control
equipment shall be inspected weekly by the facility operator to ensure it is in
good working order.
Not applicable at this facility.
(5) The operator of the facility shall inspect the exterior of all tanks for leaks,
corrosion, and maintenance deficiencies weekly. Interior inspection of tanks shall
be performed according to the Section approved plan. If the inspection reveals a
tank or equipment deficiency which could result in failure of the tank to contain
the liquid, remedial measures shall be taken immediately to eliminate the leak or
correct the deficiency. Inspection reports shall be maintained and made available
to the Section upon request for the lifetime of the liquid storage system.
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Not applicable at this facility.
(6) All uncovered tanks shall have a minimum two feet of freeboard. Odor and
vector control shall be practiced when necessary.
Not applicable at this facility.
(d) Underground tank requirements.
Underground tanks will not be utilized at this facility.
(1) Underground tanks shall be placed a minimum of two feet above the seasonal
high ground-water table and a minimum of two feet vertical separation shall be
maintained between bedrock and the lowest point of the tank.
Not applicable at this facility.
(2) Tanks may be constructed of fiberglass reinforced plastic, steel that is
cathodically protected, steel that is clad with fiberglass, or any other materials
approved by the Section.
Not applicable at this facility.
(3) The secondary containment and continuous leak detection system shall be
installed in the form of a double-walled tank, designed as an integral structure
so that any release from the inner tank is completely contained by the outer
shell.
Not applicable at this facility.
(A) The leak detection system shall be monitored at least weekly using
methods specified by the operator and approved by the Section.
Not applicable at this facility.
(B) Any tank system vulnerable to corrosion shall be protected from both
corrosion of the primary tank interior and the external surface of the
outer shell.
(i) All resistant coatings applied to the primary tank interior shall
be chemically compatible with the liquid to be stored.
(ii) Cathodic protection systems, where installed, shall be inspected
at least weekly by the facility operator and any deficiencies shall
be corrected when discovered.
Not applicable at this facility.
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(4) All underground tanks shall be equipped with an overfill prevention system which
may include, but not be limited to: level sensors and gauges, high level alarms or
automatic shutoff controls. The overfill control equipment shall be inspected
weekly by the facility operator to ensure it is in good working order.
Not applicable at this facility.
(5) Inspection and leak detection monitoring reports shall be maintained and made
available upon request for the lifetime of the liquid storage system.
Not applicable at this facility.
(e) Surface impoundment requirements.
(1) Any surface impoundment shall be constructed so that the bottom elevation of
liquid is a minimum of four feet above the seasonal high ground-water table and
bedrock.
The lined, leachate storage pond at this facility is existing, and has been
approved by NCDEQ.
(2) At a minimum, surface impoundments shall be designed and constructed with a
liner system equivalent to the liner system for the landfill unit generating the
liquid.
The lined, leachate storage pond at this facility is existing, and has been
approved by NCDEQ.
(A) A surface impoundment designed and constructed to store leachate
from a new MSWLF unit shall include a composite liner which conforms
to the requirements of Rule .1624; or
The lined, leachate storage pond at this facility is existing, and has
been approved by NCDEQ.
(B) An alternative liner system which is designed and constructed to achieve
at least an equivalent containment efficiency. An equivalence
demonstration shall be included in the permit application and shall be
approved by the Section.
The lined, leachate storage pond at this facility is existing, and has
been approved by NCDEQ.

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(3) Construction of the liner system components shall be consistent with the
pertinent requirements set forth in Rule .1624(b)(8) and (9); and a construction
quality assurance report shall be prepared by the project engineer.
The lined, leachate storage pond at this facility is existing, and has been
approved by NCDEQ.
(4) The top liner shall be protected from degradation and damage.
The lined, leachate storage pond at this facility is existing, and has been
approved by NCDEQ.
(5) A minimum of two feet of freeboard shall be maintained in the surface
impoundment. Odor and vector control shall be practiced when necessary.
The lined, leachate storage pond at this facility is existing, and has been
approved by NCDEQ.
(6) A ground-water monitoring system shall be installed and sampled in a manner
consistent with the ground-water monitoring requirements for MSWLF units as
set forth in Rules .1631 through .1637, of this Section, or using an alternative
monitoring system approved by the Section.
The lined, leachate storage pond at this facility is existing, and has been
approved by NCDEQ.
(7) An operation plan shall be prepared and followed for operation of the surface
impoundment.
The lined, leachate storage pond at this facility is existing, and has been
approved by NCDEQ.
(f) Closure of leachate storage facilities.
(1) The owner or operator of the liquid storage facility shall prepare a written
closure plan for the liquid storage facility and submit the plan with the permit
application for the solid waste management facility.
This plan shall be prepared and properly submitted.
(2) The owner or operator shall complete closure activities in accordance with the
approved closure plan and within 180 days after liquid collection has ceased.
This condition will be complied with.
(3) At closure, all solid waste shall be removed from the tank or surface
impoundment, connecting lines, and any associated secondary containment
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systems. All solid waste removed shall be properly handled and disposed of
according to federal and State requirements. All connecting lines shall be
disconnected and securely capped or plugged.
This condition will be complied with.
(A) Underground tanks shall be removed or thoroughly cleaned to remove
traces of waste and all accumulated sediments and then filled to
capacity with a solid inert material, such as clean sand or concrete
slurry. If ground water surrounding the tank is found to be
contaminated, the tank and surrounding contaminated soil shall be
removed and appropriately disposed. Other corrective actions to
remediate the contaminant plume may be required by the Department.
Not applicable at this facility since underground tanks are not utilized.
(B) Accessways to aboveground and onground tanks shall be securely
fastened in place to prevent unauthorized access. Tanks shall either be
stenciled with the date of permanent closure or removed. The secondary
containment system shall be perforated to provide for drainage.
This condition will be complied with.
(C) For surface impoundments, all waste residues, contaminated system
components (liners, etc.), contaminated subsoils, structures and
equipment contaminated with waste shall be removed and
appropriately disposed. If the ground water surrounding the
impoundment is contaminated, other corrective actions to remediate a
contaminant plume may be required by the Department. If the ground
water surrounding the impoundment is found not to be contaminated,
the liner system may remain in place if drained, cleaned to remove all
traces of waste, and both liners punctured so that drainage is allowed.
The impoundment is to be backfilled and regraded to the surrounding
topography.
This condition will be compiled with.

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B. CORRESPONDENCE RELATED TO PERMITTING

March 28, 2017

Sent Via Email – [e-mail]
Mr. Jon Creighton
Planning & Development Director
46 Valley Street
Asheville, North Carolina 28801

Subject: Sliver Filling & Waste Placement
Buncombe County MSW Landfill
Buncombe County, Permit # 1107‐MSWLF‐1996, Document ID 27551

Mr. Creighton,

The Division of Waste Management, Solid Waste Section (Section) has completed a review of
the submittal titled Sliver Filling Design & Waste Placement (DIN 27535). The document was
submitted to the Section on your behalf by Hodges, Harbin, Newberry & Tribble and received
in the Asheville Regional Office on March 20, 2017.

The submittal summarizes the discussion from a January 31, 2017 meeting at the Asheville
Regional Office with County representatives to discuss the change in surface slopes from 4
to 1 horizontal to vertical (4H:1V) to 3 to 1 horizontal to vertical (3H:1V) in MSW Phases I‐
III (Cells 1‐6). The submittal correctly states that Permit Condition No. 23 in Attachment 3
of the amended Permit does allow for post‐settlement surface slopes of 3H:1V. Given no
individual Phases were specified, it was verified at the meeting the Permit allows for 3H:1V
surface slopes on all Phases of the MSWLF. However, the submittal indicates there was an
inconsistency between language in the Permit and the Permit to Construct (PTC) application
that was not discussed at the meeting. The inconsistency identified was regarding the
topographic contours provided for Phases I‐III in the PTC application. The topographic
contours for Phases I‐III were still shown as 4H:1V even though the Permit allowed for 3H:1V.
As a result, the airspace gained by going to 3H:1V surface slopes had not been properly
accounted for or included in the Permit. In light of this information, another review of the
PTC application was initiated to understand the discrepancy and the resulting inaccuracy in
capacity information.

Based on this review, it has been determined Permit Condition No. 23 in the Permit to
Operate (DIN 25340) issued on February 17, 2016, and referenced in the submittal, is
erroneous. The Facility Plan in the Permit to Construct Application for MSW Phase IV (Cell
7) (DIN 20913) also included a steepening of post‐settlement surface slopes from 4H:1V to
3H:1V. Section 1.4 of the Facility Plan states, “As shown on Sheets LO‐2 through LO‐5, the final
sideslopes for Phase IV through VII have been steepened to a maximum 3 to 1 (horizontal to
Mr. Jon Creighton
Sliver Filling & Waste Placement
March 28, 2017
Page 2 of 2
vertical) to increase capacity.” Additionally, the Geotechnical Design Memorandum provided
in Appendix 3B of the Engineering Plan states, “The proposed closure side slopes for Cells 7, 8,
9, and 10 and the vertical expansion (Phases IV through VII) will be 3 horizontal to 1 vertical
(3H:1V).” These statements clearly indicate the application only considered steepening the
side slopes for Phases IV through VII (Cells 7‐10, Vertical Expansion). Additionally, the
application provides no information which would allow for a determination to be made
regarding the acceptability of 3H:1V slopes for Phases I‐III (Cells 1‐6). Permit Condition No.
23 is not consistent with the currently approved plans and must be revised to limit 3H:1V
slopes for Phases IV‐VII (Cells 7‐10, Vertical Expansion). In order for 3H:1V slopes to be
permitted for Phases 1‐3 (Cells 1‐6), the facility plans must be revised to include the relevant
information and submitted to the Section for review.

In addition to the 3H:1V slope issue, the submittal also discussed the intention of the
County to delay construction of Phase IV (Cell 7) while placing waste at 3H:1V within
Phases I‐III (Cells 1‐6). The submittal states this delay would be beyond the 18 months
specified in Permit Condition No. 18 in Attachment 2 which would mean the PTC for Phase
IV would expire. The submittal requests an allowance be made for a continuation of the
approval to construct Phase IV until that area is needed. Permit Condition No. 18 is a
standard condition and allows for the Section to enforce Statute or Rule changes that may
be passed once a PTC has been issued but no construction has started within the stated
timeline. This permit condition cannot be modified. However, once the Permit is revised to
fix the error, the issuance date will be changed to restart the clock. Additionally, assuming
no Statute or Rule changes, the issuance date can be changed with any subsequent Permit
modifications to push the expiration date further into the future.

Finally, the submittal requested a Life of Site Permit be issued during the next permitting
activity. The next Permit to be issued for the Buncombe County facility will be Life of Site
with no expiration date.

If you should have any questions regarding this matter please contact me at (828) 296‐
4703, or by email at [e-mail] .

Sincerely,
Allen Gaither
Environmental Engineer

CC: Mr. Joe Wiseman – Environmental Infrastructure Consulting
Mr. Matt Cheek – Hodges, Harbin, Newberry & Tribble
Mr. Stephen Hunter – Buncombe County
Ms. Kristy Smith – Buncombe County
Mr. Kris Riddle – SWS/ARO
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May 2017 HHNT Project No. 1401-010-01

C. FACILITY DRAWINGS

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May 2017 HHNT Project No. 1401-010-01

D. APPENDIX

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May 2017 HHNT Project No. 1401-010-01

1. C&D LANDFILL FACILITY REPORT

Buncombe County,
North Carolina

Buncombe County Solid Waste
Management Facility

C&D Landfill Expansion
Part 3: Facility Plan
April 2009

Part 3: Facility Plan
Contents
Section 1 – Facility Drawings
1.1 Site Development ...................................................................................................... 1-1
1.2 Landfill Operation .................................................................................................... 1-1
Section 2 – Facility Report
2.1 Waste Stream ............................................................................................................. 2-1
2.1.1 Types of Waste Specified for Disposal ................................................... 2-1
2.1.2 Disposal Rates ............................................................................................ 2-1
2.1.3 Areas Served by the Facility .................................................................... 2-2
2.1.4 Segregated Management .......................................................................... 2-2
2.1.5 Landfill Equipment ................................................................................... 2-2
2.2 Landfill Capacity ...................................................................................................... 2-3
2.2.1 Gross Capacity ........................................................................................... 2-3
2.2.2 Phased Gross Capacity ............................................................................. 2-3
2.2.3 Soil Required for Landfill Construction ................................................. 2-3
2.2.4 Soil Required for Final Cover .................................................................. 2-3
2.2.5 Soil Required for Operations ................................................................... 2-4
2.2.6 Net Capacity ............................................................................................... 2-4
2.2.7 C&D Landfill Operating Life ................................................................... 2-4
2.2.8 Net Balance of On-site Soils ..................................................................... 2-5
2.3 Special Engineering Features .................................................................................. 2-6
2.3.1 Containment and Environmental Control Systems ............................. 2-6
2.3.1.1 Closure Cap System ............................................................... 2-6
2.3.1.2 Sedimentation and Erosion Control .................................... 2-6
2.3.1.3 Landfill Subgrade .................................................................. 2-6

Tables
Table 2-1 – Disposal Rates .................................................................................................... 2-2
Table 2-2 – Phased Gross Capacity ..................................................................................... 2-3
Table 2-3 – Operating Life .................................................................................................... 2-4
Table 2-4 – Net Soils Balance ................................................................................................ 2-5

Appendices
Appendix A Facility Plan Drawings
Appendix B Location Restrictions
A i

Section 1
Facility Drawings
A set of facility drawings have been prepared in compliance with Rule .0537 (d).
These drawings include conceptual site development and landfill operation sheets
and are included in Appendix A.
1.1 Site Development
Three drawings were prepared on topographic maps representative of existing site
conditions. The first drawing, Sheet SD-1, contains a topographical survey of the
entire site representative of existing site conditions locating all property boundaries
for the proposed landfill facility certified by an individual licensed to practice land
surveying in the State of North Carolina. Also included is the following:
• areal limits of all solid waste management facilities and facility infrastructure,
including landfill units and buffer requirements set forth in 15A NCAC 13B
.0540(1);
• areal limits of borrow and stockpile; and
• any physical features referenced in Rule 15A NCAC 13B .0536 (Location
Restrictions).
Sheet SD-2 illustrates the phases of development and areal limits of grading. Sheet
SD-3 depicts the proposed final contours for the C&D landfill unit and facility feature
for closure.
1.2 Landfill Operation
Landfill Operation Sheets 1-5 show the proposed transitional contours and
construction grading for the new phases. Five drawings were prepared detailing the
long-term operation of the C&D landfill unit. Proposed transitional contours and
final grades for each phase of development (Phases 5 through 8) are shown on
Drawings LO-1 through LO-5.

A 1-1

Section 2
Facility Report
This facility report contains characteristics of the waste stream to be received at the
landfill facility and of the landfill capacity as required by Rule .0537(e).
2.1 Waste Stream
Per Rule .0537(e)(1), a discussion of the characteristics of the waste received at the
facility and facility specific management plans is as follows.
2.1.1 Types of Waste Specified for Disposal
From the Permit to Operate – Asbestos Modification, dated March 5, 2008, the County
is permitted to dispose of construction or demolition debris, inert debris, land-
clearing debris, and asphalt in accordance with the corresponding General Statute.
The C&D landfill is also permitted to dispose of asbestos waste in accordance with
Rule .0542(c) and must be managed per 40 CFR 61.
Waste, listed in Rule .0542(e), may not be accepted for disposal including, but not
limited to yard trash, municipal solid waste, and liquid or industrial wastes.
The County will continue to dispose of waste types as specified in the current Permit
to Operate.
2.1.2 Disposal Rates
Table 2-1 presents yearly disposal rates as provided by the County scale house and
includes a representative daily rate assuming 284 operating days (365 days - 52
Sundays - 26 Saturdays (half days) - 3 holidays). It is anticipated that the annual
amount of waste to be disposed will be approximately 63,000 tons of C&D waste per
year (222 tons per day).

A 2-1

Section 2
Facility Report

Table 2-1 – Disposal Rates
FY1 Tons Disposed Daily Rate (tons/day)
98-99 30,898 109
99-00 43,147 152
00-01 43,370 153
01-02 24,238 85
02-03 8,209 29
03-04 29,889 105
04-05 39,252 138
05-06 58,730 207
06-07 66,388 234
07-08 62,849 222
1Fiscal year is from July to June.

2.1.3 Areas Served by the Facility
The Buncombe County C&D landfill will serve only waste streams originating from
Buncombe County. Buncombe County, approximately 659 square miles in area,
includes the incorporated municipalities of Asheville, Biltmore Forest, Black
Mountain, Montreat, Weaverville, and Woodfin.
2.1.4 Segregated Management
The Buncombe County Solid Waste Management Facility staff place a high priority on
proper management of incoming waste. The same level of concern and effort is put
forth for the operation of the C&D landfill. Waste screening and segregation
procedures are included in the Operation Plan.
2.1.5 Landfill Equipment
Equipment currently owned by the County and utilized at the C&D landfill includes
the following:
• 1 – 390-E Trashmaster
• 1 – D-6 CAT Dozer
• 1 – Waste Screening Vehicle (Ford F-150 Truck)
A 2-2
Section 2
Facility Report

No additional equipment purchases are anticipated as a result of expanding the C&D
disposal capacity.
2.2 Landfill Capacity
2.2.1 Gross Capacity
AutoCAD Civil 3D 2008 software was used to estimate the gross capacity between the
base grades and the top of the proposed final cover grades for the proposed C&D
landfill. The gross capacity (waste and daily, intermediate, and final cover) of the
landfill is approximately 1.7 million cubic yards (cy).
2.2.2 Phased Gross Capacity
AutoCAD Civil 3D 2008 software was used to estimate the phased gross capacity and
is presented in Table 2-2.
Table 2-2 – Phased Gross Capacity
Phase Gross Capacity (cy)
5 285,500
6 607,700
7 612,600
8 159,700
Total 1,665,500

2.2.3 Soil Required for Landfill Construction
Soil is required for landfill construction to install access/haul roads, stormwater
control measures, and, when necessary, to establish the required minimum four feet
separation between the bottom elevation of waste and seasonal high groundwater
table and the bedrock datum plane contours. For the Buncombe County C&D
landfill, seasonal high groundwater table is below bedrock, so the bedrock contours
govern the four feet separation when applicable.
2.2.4 Soil Required for Final Cover
The final cover material volume required to construct the three-foot thick cover
system for each phase is determined by delineating final slopes (see Table 3-3).
Required Final Cover = Final Cover Area x 3-foot Thick Cover System
A 2-3
Section 2
Facility Report
2.2.5 Soil Required for Operations
It is anticipated that the County will use an alternative cover material for the required
weekly cover. An intermediate, stabilizing material will be used for areas which will
not have additional wastes placed on them for three months or more, but where final
termination of disposal operations has not occurred. When the County resumes
disposal in these areas, they will scrap off the intermediate cover and use it for the
final cover once areas are at final grades.
2.2.6 Net Capacity
Table 3-3 present the net capacity available for C&D debris disposal is calculated as:
Net Capacity = Gross Capacity – Final Cover
2.2.7 C&D Landfill Operating Life
The first step in calculating the operating life of each C&D landfill phase is to convert
available net airspace to available C&D debris tonnage. From the July 2008 Airspace
Analysis Report, the C&D in-place density is 0.65 tons per cubic yard (cy) (the
calculated in-place density includes operational soils). Available tonnage is calculated
as:
Available Tonnage = Net Capacity x 0.65 tons/ cy
The approximate average disposal rate for the C&D landfill for the past three fiscal
years is 63,000 tons per year from Table 2-1. An average disposal rate of 63,000 tons
per year is used in the following calculation. Table 2-3 presents the estimated
operating life for the C&D disposal unit is, therefore, calculated as:
Operating Life = Available Tonnage/Average Disposal Rate
Table 2-3 – Operating Life
Phase Final Cover
Area (acre)
Soil Required for
Final Cover (cy)
Available Net
Airspace (cy)
Operating Life
(yrs)
5 10.7 51,800 233,700 2.4
6 5.9 28,600 579,100 6.0
7 7.7 37,300 575,300 5.9
8 5.4 26,200 133,600 1.4
TOTAL 1,521,700 16

A 2-4
Section 2
Facility Report
2.2.8 Net Balance of On-site Soils
Earthwork fill volume associated with the construction of each phase of the C&D
landfill was estimated based on the proposed base grades and governing four feet of
separation. A volume computation, using AutoCAD Civil 3D 2008, resulted in an
even cut/fill soil balance for the construction of Phase 5. Phase 6 soil balance during
construction was calculated to be a soil surplus of approximately 104,000 cy. Phases 7
and 8 are vertical expansions and will not require soil for construction. Table 2-4
presents the net soil required for construction and closure of each phase and was
calculated by the following:
Fill + Final Cover = Net Soil Required
Table 2-4 – Net Soils Balance
Phase
Net Soil Required (yd3)
Construction Final Cover TOTAL
5 0 51,800 51,800
6 -104,000 28,600 -75,400
7 0 37,300 37,300
8 0 26,200 26,200

Soil materials for construction of the landfill base and cap will be obtained from the
on-site borrow areas as presented on Sheet SD-1. The current borrow source area is
being exhausted and the County proposes to move into the proposed borrow source
area as delineated on Sheet SD-1 on contingency of North Carolina Department of
Environment and Natural Resources, Solid Waste Section (NCDENR SWS) approval.
The proposed borrow source area has a potential soil volume of approximately
645,000 cy. Assuming a swell factor of 1.25 the loose soil volume is approximately
806,000 cy. Also, assuming the County using 300 cy of soil a day, working 284 days
per year, the proposed borrow source life is approximately 9 to 10 years.
As stated, the proposed borrow source area will provide adequate soil for operations
and final cover for the proposed C&D landfill expansion.
A 2-5
Section 2
Facility Report
A 2-6
2.3 Special Engineering Features
2.3.1 Containment and Environmental Control Systems
2.3.1.1 Closure Cap System
A closure cap will be designed and constructed when portions of the C&D landfill are
at closure grades to reduce the infiltration and erosion per Rule .0543 (c)(1). The cap
system will be 3-foot thick and be designed and constructed to:
(A) have a permeability less than or equal to soils underlying the landfill, or
the permeability specified for the final cover in the effective permit, or a
permeability no greater than 1.0 x 10-5 cm/sec, whichever is less;
(B) minimize infiltration through the closed C&DLF unit by the use of a low-
permeability barrier that contains a minimum 18 inches of earthen
material; and
(C) minimize erosion of the cap system and protect the low-permeability
barrier from root penetration by use of an erosion layer that contains a
minimum of 18 inches of earthen material that is capable of sustaining
native plant growth.
A gas venting or collection system will be installed below the low-permeability
barrier to minimize pressures exerted on the barrier.
2.3.1.2 Sedimentation and Erosion Control
A Sedimentation and Erosion Control Plan will be submitted for approval to the
NCDENR, Land Quality Section before construction of each phase. Internal
stormwater berms will be utilized to minimize the amount of stormwater that comes
in contact with waste. Temporary erosion control measures, such as silt fences, fast
germinating vegetation, rock check dams, etc. will be installed as necessary to reduce
the amount of sedimentation and erosion during construction activities.
2.3.1.3 Landfill Subgrade
Per Rule .0540 (2), each proposed phase will be constructed so that the post-settlement
bottom elevation of waste is a minimum of four feet above the seasonal high
groundwater table as established in the Design Hydrogeological Report (see Part 5 of
this report). Additionally, per Rule .0540 (2)(b), on-site soils will be used to construct
the upper two feet of separation since they meet and/or exceed the required soil
classifications.
Part 3
Facility Plan

Appendix A
Facility Plan Drawings
Part 3
Facility Plan

Appendix B
Location Restrictions

Appendix B – Location Restrictions
Facility Plan – C&D Landfill
Contents
Section 1 – Location Restrictions
1.1 Floodplains ................................................................................................................ 1-1
1.2 Wetlands .................................................................................................................... 1-2
1.2.1 Regulatory Background ............................................................................ 1-2
1.2.2 Compliance Issues ..................................................................................... 1-3
1.3 Unstable Areas .......................................................................................................... 1-3
1.3.1 Regulatory Background ............................................................................ 1-3
1.3.2 Compliance Issues ..................................................................................... 1-3
1.4 Cultural Resources ................................................................................................... 1-3
1.5 State Nature and Historic Preserves ...................................................................... 1-4
1.6 Water Supply Watersheds ....................................................................................... 1-4
1.7 Endangered and Threatened Species ..................................................................... 1-5

Attachments
Attachment A – Floodplain Map
Attachment B – PCN Form and Nationwide Permitting Approval Letters
Attachment C – State Historic Preservation Office/
Department of Cultural Resources Correspondence
Attachment D – Natural Heritage Program Correspondence
Attachment E – US Fish and Wildlife Service Correspondence
A i

Section 1
Location Restrictions
Rule .0539 (d)(1)(D) of the North Carolina Solid Waste Management Rules requires
that a report be prepared and submitted demonstrating compliance with the location
restriction criteria in Rule .0536. Rule .0536 requires documentation or approvals by
agencies other than the Division of Waste Management, Solid Waste Section that
demonstrate compliance with specific location criteria. It is the intent of this section
to provide location restriction demonstration for the C&D landfill facility plan. The
location restrictions include:
• Floodplains;
• Wetlands;
• Unstable areas;
• Cultural resources;
• State nature and historic preserve;
• Water supply watersheds; and
• Endangered and threatened species.
CDM has reviewed available information pertaining to location restriction criteria
relative to the proposed Buncombe County C&D landfill expansion. The following
sections summarize the findings.
1.1 Floodplains
Rule .0536(c)(4), floodplain location restrictions, states:
(A) C&DLF units or constructed embankments used to construct a C&DLF unit
must not be located in a 100-year floodplain unless a variance for the facility
has been issued in accordance with N.C.G.S. 143-215.54A.
(B) C&DLF units must not be located in floodplains unless the owners or
operators demonstrate that the unit will not restrict the flow of the flood,
reduce the temporary water storage capacity of the floodplain, or result in
washout of solid waste so as to pose a hazard to human health and the
environment.
Based on floodplain maps for the Buncombe County area, no portion of the
Buncombe County property resides in the 100-year floodplain (see Attachment A).
Areas around the French Broad River and Flat Creek are denoted as AE; area
inundated by 100-year flooding, before flood elevation have been determined.
A 1-1

Section 1
Location Restrictions

1.2 Wetlands
1.2.1 Regulatory Background
Rule .0536 (c)(5) requires that new C&DLF units or lateral expansions must not be
located in wetlands, unless the owner or operator can make the following
demonstrations to the Division:
(A) Where applicable under Section 404 of the Clean Water Act or applicable
State wetlands laws, the presumption that a practicable alternative to the
proposed landfill facility is available which does not involve wetlands is
clearly rebutted.
(B) The construction and operation of the C&DLF unit(s) will not cause or
contribute to violations of any applicable State water quality standards and
will not violate any applicable toxic effluent standard or prohibition under
Section 307 of the Clean Water Act.
(C) The construction and operation of the C&DLF unit(s) will not jeopardize the
continued existence of endangered or threatened species or result in the
destruction or adverse modification of a critical habitat, protected under the
Federal Endangered Species Act of 1973. The construction and operation of
the C&DLF unit(s) will not violate any requirement under the Marine
Protection, Research, and Sanctuaries Act of 1972 for the protection of a
marine sanctuary.
(D) The construction and operation of the C&DLF unit(s) will not cause or
contribute to significant degradation of wetlands.
(E) The owner or operator must demonstrate the integrity of the C&DLF unit(s)
and its ability to protect ecological resources by addressing the following
factors: (1) erosion, stability, and migration potential of native wetland soils,
muds and deposits used to support the C&DLF unit; (2) erosion, stability, and
migration potential of dredged and fill materials used to support the C&DLF
unit; the volume and chemical nature of the waste managed in the C&DLF
unit; (3) impacts on fish, wildlife, and other aquatic resources and their
habitat from release of the solid waste; (4) the potential effects of catastrophic
release of waste to the wetland and the resulting impacts on the environment;
and (5) any additional factors, as necessary, to demonstrate that ecological
resources in the wetland are sufficiently protected to the extent required
under Section 404 of the Clean Water Act or applicable State wetlands laws.
(F) The owner or operator must demonstrate that steps have been taken to
attempt to achieve no net loss of wetlands (as defined by acreage and
function) by first avoiding impacts to wetlands to the maximum extent
practicable as required by Part (c)(5)(A) – (D) of this Rule, then minimizing
unavoidable impacts to the maximum extent practicable, and finally
A 1-2
Section 1
Location Restrictions

offsetting remaining unavoidable wetland impacts through all appropriate
and practicable compensatory mitigation actions (e.g., restoration of existing
degraded wetlands or creation of man-made wetlands).
(G) The owner or operator must also demonstrate that sufficient information is
available to make a reasonable determination with respect to each of the
demonstrations required by this Rule.
1.2.2 Compliance Issues
CDM and the US Army Corps of Engineers (USACE) conducted a site visit on
October 28, 2008 to determine if drainage features located north of each expansion site
were jurisdictional, as subject to regulations under the Clean Water Act.
Jurisdictional waters were determined and the County prepared and submitted a
Preconstruction Notification (PCN), which served as a joint application for a Section
404 Permit from USACE and a 401 Water Quality Certification from the North
Carolina Division of Water Quality (NCDWQ). Included as Attachment B are the
PCN form and the approval letters.
1.3 Unstable Areas
1.3.1 Regulatory Background
Rule .0536 (c)(6) states that owners and operators of new C&DLF unit(s) and lateral
expansions proposed for location in an unstable area must demonstrate that
engineering measures have been incorporated in the C&DLF unit's design to ensure
that the integrity of any structural components of the C&DLF unit will not be
disrupted. The owner and operator must consider the following factors, at a
minimum, when determining whether an area is unstable:
(A) On-site or local soil conditions that may result in significant differential
settling;
(B) On-site or local geologic or geomorphologic features; and
(C) On-site or local human-made features or events (both surface and
subsurface).
1.3.2 Compliance Issues
Based on the site and design hydrogeological and geotechnical investigation
completed for this report and previously approved reports, the geological and soil
conditions that are presumed to be throughout the site are not prone to unstable
conditions.
A 1-3
Section 1
Location Restrictions

1.4 Cultural Resources
Rule .0536 (c)(7) states that a new C&DLF unit or lateral expansion must not damage
or destroy a property of archaeological or historical significance which has been listed
or determined eligible for a listing in the National Register of Historic Places.
Correspondence with the State Historic Preservation Office in the Department of
Cultural Resources is included in Attachment C.
Based on the correspondence, there is no documentation that significant cultural
resources exist within or in the vicinity of the site. No cultural resources are expected
to be adversely affected by the C&D landfill development.
1.5 State Nature and Historic Preserves
Rule .0536 (c)(8) states that a new C&DLF unit or lateral expansion must not have an
adverse impact, considering the purposes for designation of the Preserve lands and
the location, access, size and operation of the landfill, on any lands included in the
State Nature and Historic Preserve.
The NC Natural Heritage Program (NHP) was contacted to determine if any state
natural preserves exist within or in the vicinity of the proposed C&D landfill
expansion (see Attachment D). Based on the NHP correspondence, no state nature or
historical preserves would be impacted by development within the facility boundary.
1.6 Water Supply Watersheds
Rule .0536 (c)(9)(A) states that a new C&DLF unit or lateral expansion must not be
located in the critical area of a water supply watershed, or in the watershed for a
stream segment classified as WS-I, or in watersheds of other water bodies which
indicate that no new landfills are allowed in accordance with the rules codified at 15A
NCAC 02B Section .0200 entitled "Classifications and Water Quality Standards
Applicable To Surface Waters Of North Carolina."
The State has classified all surface waters and watersheds throughout the state as
required by 15A NCAC 2B .0311 as referenced by Rule 2B .0200. These classifications
are made available by NCDENR Division of Water Quality.

Based on the classification list and NC OneMap program data and on-line map (used
on April 2009) from NCDENR, CGIA, the proposed site is not located in an area that
will impact or discharge to a WS-1, WS-II, WS-III, or WS-IV watershed. Therefore, the
proposed location is in compliance with Water Supply Watershed rules.
Rule .0536 (c)(9)(B) states that any new C&DLF unit or lateral expansion, which
proposes to discharge leachate to surface waters must obtain a National Pollution
Discharge Elimination System (NPDES) Permit from the Division of Environmental
Management pursuant to Section 402 of the United States Clean Water Act, must not
be located within watersheds classified as WS-II or WS-III, or in watersheds of other
A 1-4
Section 1
Location Restrictions

A 1-5
water bodies which indicate that no new discharging landfills are allowed, in
accordance with the rules codified at 15A NCAC 02B Section .0200.
The C&D landfill facility is not located within any of these classified watersheds and
will not discharge leachate into any surface water locations and therefore is not
expected to apply for a NPDES permit.
1.7 Endangered and Threatened Species
Rule .0536 (c)(10) states that a new C&DLF unit or lateral expansion must not
jeopardize the continued existence of endangered or threatened species or result in
the destruction or adverse modification of a critical habitat, protected under the
Federal Endangered Species Act of 1973.
CDM contacted US Fish and Wildlife Service (US FWS) office to determine whether
there was any documentation that endangered or threatened species existed within
the site or its vicinity. Correspondence with the US FWS is included in Attachment E.
Based on the US FWS, there are no federally-listed endangered or threatened species,
their formally designated critical habitat, or species currently proposed for listing
under the Endangered Species Act within the proposed facility boundary.

Part 3 - Facility Plan
Appendix B – Location Restrictions

Attachment A
Floodplain Map
Part 3 - Facility Plan
Appendix B – Location Restrictions

Attachment B
PCN Form and Nationwide Permitting
Approval Letters
Part 3 - Facility Plan
Appendix B – Location Restrictions

Attachment B1
USACE Jurisdictional Determination
Part 3 - Facility Plan
Appendix B – Location Restrictions

Attachment B2
PCN Form
Part 3 - Facility Plan
Appendix B – Location Restrictions

Attachment B3
Nationwide Permitting
Approval Letters
Part 3 - Facility Plan
Appendix B – Location Restrictions

Attachment C
State Historic Preservation Office/
Department of Cultural Resources Correspondence
Part 3 - Facility Plan
Appendix B – Location Restrictions

Attachment D
Natural Heritage Program Correspondence
Part 3 - Facility Plan
Appendix B – Location Restrictions

Attachment E
US Fish and Wildlife Service Correspondence

2017 Facility Plan Modification
Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

2. ENGINEERING PLAN UPDATES

2017 Facility Plan Modification
Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

I. INTRODUCTION
As part of this Facility Plan modification, HHNT has prepared several supplemental calculations or
evaluations to address items that would typically be included in an Engineering Permit to Construct
Document. The last Permit to Construct document that was approved was prepared by CDM Smith
and dated April 28, 2014. That document included the necessary information for design and
permitting Phase IV (Cell 7) of the Subtitle D landfill facility. The designs and evaluations included in
that permit application were generally limited to Cell 7, and the proposed change from 4H:1V to a
final slope inclination of 3H:1V within the Vertical Expansion Area, which included Cells 7-10.
The purpose of this Facility Plan modification is to extend that 3H:1V final grading change into Cells
1-6. Since all six (6) of those cells are already constructed, it is unnecessary to provide another
complete Permit to Construct permit application for those previously constructed cells. However,
there are some items that warrant further evaluation to confirm that the increased slope and
associated waste height will not negatively impact the constructed infrastructure within those cells.
Below is a summary of the back-up calculations included in the Cell 7 PTC application that
representatives of NC DEQ have requested to be reviewed. Please note that our review of these
calculations was not intended to confirm the accuracy of the previous consultants work, instead,
this review was performed to determine the applicability of these calculations to modifying the final
grades in Cells 1-6 at 3H:1V so that a decision could be made as to whether or not these
calculations are adequate for Cells 1-6 or they need to be redone for the Cell 1-6 area of waste
filling. These calculations include:
Appendix A-1: Fabric Puncture Protection
Appendix A-2: Anchor Trench Pullout
Appendix A-3: HELP Model
Appendix A-4: Pipe Strength
Appendix A-9: Stormwater Management System
Appendix A-11: Geomembrane Elongation Strain
Appendix B: Geotechnical Evaluation
Engineering Drawings

A summary is provided below regarding each of the calculation sections that where reviewed:
Appendix A-1: Fabric Puncture Protection Evaluation Summary:
The Fabric Puncture Protection calculation prepared by CDM-Smith as part of the Engineering Plan
included in the Phase IV (Cell 7) Permit to Construct Application dated April, 2014 was reviewed.
This calculation assumes a total depth of waste/material over the cushion to be 140 feet and a
composite unit weight on top of the cushion material of 90 lbs/cf. The factor of safety for a 28
2017 Facility Plan Modification
Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

oz/sy nonwoven geotextile fabric cushion material was determined to be 2.0 which exceeds the
minimum desired factor of safety of 1.0.
We understand that a similar liner system was used during the construction of Cells 1-6. Based on
the increased waste height within Cells 1-6 due to revising the permit grades to a final slope grade
of 3H:1V, the maximum depth of waste/material over the cushion will be a total of 160 feet. We
believe that a composite unit weight of 90 lbs/cf is conservatively appropriate for this particular
facility. Since the conditions and / or assumptions that would be used to evaluate the vertical
increase in Cells 1-6 are different than what was originally demonstrated. An updated calculation
has been provided in Section D. (2.) II. the Engineering Plan Update.
Appendix A-2: Anchor Trench Pullout Evaluation Summary:
The Anchor Trench Pull-out calculation prepared by CDM-Smith as part of the Engineering Plan
included in the Phase IV (Cell 7) Permit to Construct Application dated April, 2014 was reviewed.
The purpose of this calculation is to evaluate the critical interface between the geomembrane and
GCL to determine whether or not the geomembrane material will pull-out of the anchor trench
prior to exceeding the allowable tensile strength of the geomembrane material to prevent a tear or
rupture in the geomembrane liner during initial waste filling activities.
Re-evaluating this calculation is not necessary within the vertical expansion area since waste
placement has already occurred over the entire area. In addition, based on our review, it appears
the permitted design provides a 4’ run-out of the liner with no anchor trench at all.
Appendix A-3: HELP Model Evaluation Summary:
The HELP Model Evaluation prepared by CDM-Smith as part of the Engineering Plan included in the
Phase IV (Cell 7) Permit to Construct Application dated April, 2014 was reviewed. The purpose of
HELP modeling is to evaluate the performance of a leachate collection system and landfill liner
systems using local weather data to predict leachate production rates, liner leakage rates, and
leachate head over the liner. Typically, a HELP Model evaluation evaluates multiple cases, or
scenarios to determine the worst case condition. The four (4) cases evaluated in the Cell 7 PTC
application include:
• Case 1 – First Lift of Waste—(i.e. 10 ft of waste and 6 inches of daily cover)
• Case 2 – Active Operation—(i.e. 30 ft of waste and 6 inches of daily cover)
• Case 3 – Intermediate Cover –(i.e. 90 ft of waste and 12 inches of intermediate cover with
75% of all leachate generated being recirculated within the top 45 ft of waste)
• Case 4 – Final Buildout—(i.e. 90 ft of waste and final cover in place)

The worst case condition was determined to be Case 1. This is consistent with HHNT’s experience
in that the worst case condition typically occurs in a Case 1 or Case 2 scenario—which is many times
prior to the waste mound being at a sufficient height to shed stormwater runoff down the outside
2017 Facility Plan Modification
Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

slopes. Since the existing leachate collection system and liner systems for Cells 1-6 should have
been designed to handle the worst case condition, we do not believe additional calculations are
necessary to demonstrate the adequacy of these systems due to the vertical expansion. Based on
the current waste material in place, it is expected that the facility is more accurately represented by
the Case 3 condition at this time, which is not the worst case.
Appendix A-4: Pipe Strength Evaluation Summary:
Due to the increased height of waste (and loading) associated with revising the final grades in Cells
1-6 to 3H:1V, the structural design of the existing leachate collection pipes has been re-evaluated.
A summary of that evaluation has been included in Section D. (2.) III. of this Engineering Plan
Update.
Appendix A-9: Stormwater Management System Evaluation Summary:
Detailed stormwater management system calculations were prepared by CDM-Smith as part of the
Engineering Plan included in the Phase IV (Cell 7) Permit to Construct Application dated April, 2014.
These calculations focused on the area draining to Sediment Basin No. 2, which primarily includes
the Cell 7 area. The stormwater management calculations do not provide coverage over the entire
landfill footprint.
The overall drainage areas for the remaining areas of the landfill will remain relatively unchanged,
even with the vertical height increase associated with re-grading the final contours at 3H:1V in
existing Cells 1-6. While there may be some nominal increase in the overall drainage area due to
the 3-dimensional surface area increase associated with the increased height, the new contours do
not attempt to re-direct or significantly alter the current drainage patterns. The new grades
generally follow the existing grades. The proposed modification makes no attempt to change or
alter the existing perimeter drainage channels, existing pipe culverts, or existing basins.
We do believe that the increased slope could impact the overall hydraulic routing calculations, since
stormwater runoff will travel faster down a 3H:1V sideslope than the current slopes and the time of
concentration will likely change. However, since it is unlikely that the final sideslopes will match the
design grades exactly during final closure, we would respectfully request that detailed stormwater
drainage calculations be included with the Final Closure Construction documents which will be
submitted to the NC DEQ Solid Waste Section prior to any closure event beginning. At that time,
detailed calculations, based on actual conditions at the time of closure, can be prepared and
submitted to the Section for review.
Appendix A-11: Geomembrane Elongation Strain Evaluation Summary:
The Geomembrane Elongation Strain evaluation prepared by CDM-Smith as part of the Engineering
Plan included in the Phase IV (Cell 7) Permit to Construct Application dated April, 2014 was
reviewed. The purpose of this calculation was to estimate the anticipated strain within the
2017 Facility Plan Modification
Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

geomembrane liner due to differential settlement. The minimum average tensile property for yield
elongation of 60 mil High Density Polyethylene (HDPE) Geomembrane Textured Liner is 12%.
(reference GRI GM13 standards)
The CDM evaluation looked at several cases to determine the % Strain (Elongation) for the
anticipated worst case differential settlement areas within Cell 7. The worst case % Strain
(Elongation) was determined to be 0.13%, which is almost an order of magnitude less than the
allowable 12%.
It is virtually impossible to re-create or re-calculate the anticipated % Strain (Elongation) in existing
Cells 1-6 based on available data. However, due to the assumed similarities in geologic properties,
hydrogeologic properties, liner systems, and materials used, it appears unlikely that the increased
waste height of ± 20-30 feet of additional waste over these existing cells would be enough to
exceed the allowable 12% Strain (Elongation).
Appendix B: Geotechnical Evaluation Evaluation Summary:
Due to the increased height of waste associated with revising the final grades in Cells 1-6 to 3H:1V,
overall slope stability within this area of the landfill has been further evaluated. A summary of that
evaluation has been included in Section D. (2.) IV. of this Engineering Plan Update.
Engineering Drawings Evaluation Summary:
All Facility Plan drawings have been reviewed and updated as necessary to reflect the change in
final grades from 4H:1V to 3H:1V in existing Cells 1-6. Please refer to Section C of this report for a
complete set of updated drawings.

2017 Facility Plan Modification 
Buncombe County Solid Waste Management Facility  Buncombe County, NC 
May 2017  HHNT Project No. 1401‐010‐01 

II.  FABRIC PUNCTURE PROTECTION OF EXISTING GEOMEMBRANE  
This calculation is typically performed to demonstrate that a selected cushion geotextile will 
provide an acceptable factor of safety against puncture of the underlying geomembrane. The 
calculated factor of safety within an area of the landfill is variable, depending on the depth of 
waste, assumed waste density, and thickness of the cushion geotextile. Therefore, the calculations 
provided for Cell 7 are not applicable to Cells 1‐6 and this calculation was re‐confirmed.  

To accurately calculate the factor of safety against puncture in Cells 1‐6, information regarding the 
in place materials (cushion geotextile) is necessary. Unfortunately, specific details regarding that 
material were not readily available. Therefore, HHNT took an alternate approach to confirming this 
calculation by working to determine the minimum required cushion geotextile thickness to provide 
a factor of safety of at least 1.0. The worst case (greatest depth of waste) occurs in Cells 3 and 4 
where the height of waste above the geomembrane is about 20 feet higher than previously 
designed and was evaluated. The calculation is provided in this section.  

To evaluate the potential for the weight of the additional waste to puncture the existing 
geomembrane, HHNT modeled a 10 oz/yd2 non‐woven geotextile which is assumed to be a much 
lighter cushion geotextile than what was actually installed. That calculation indicated a factor of 
safety of at least 1.5 against puncture of the existing geomembrane which is also greater than the 
minimum desired factor of safety equal to 1.0.   Based on information from the Phase IV (Cell 7) 
Permit to Construct Application (CDM Smith Application), the cushion geotextile actually installed in 
Cells 3 and 4, is similar to that permitted for Cell 71.  Since Cell 7 includes a 28 oz/yd2 cushion 
geotextile, it is expected that the cushion geotextile installed in previous cells was heavier than 10 
oz/yd2, therefore it can be concluded that the existing geomembrane is sufficiently protected 
against puncture under the weight of the expansion. 

1 See Section 1.1 of the Engineering Design Section of the 2014 CDM Smith Application 
C:\Users\cmoeller\Documents\Buncombe LF Expansion\
LF Puncture Calculation v_0 v1_0.xlsx 1 of 3
Project:
Date:
Job#:
Objective
Method
where:FS =
Pact =
Pallow
pallow is determined by the following equation (Ref. 3):
where:
Symbol Unit
Pallow kPa
M g/m2
H m
MFS -
MFPD -
MFA -
RFCR -
RFCBD -
Angular:1 Isolated 1 Hydrostatic 1
Subrounded:0.5 Dense, 38 mm 0.83 Geostatic,
shallow 0.75
Dense, 25 mm 0.67 Geostatic,
mod.0.5
Dense, 12mm 0.5 Geostatic,
deep 0.25
1.1
1.3 38 25 12
1.5 (mm) (mm) (mm)
Geomembrane
alone
N/R N/R N/R N/R = Not Recommended
1.5 inches 270 N/R N/R >1.5
or = 38.1 mm 550 N/R 1.5 1.3
1100 1.3 1.2 1.1
>1100 1.2 1.1 1
Pallow / PactFS =
factor of safety against geomembrane puncture
allowable pressure using different types of geotextiles and site specific conditions.
reduction factor for long-term chemical/biological degradation
modification factor for protrusion shape
modification factor for packing density
modification factor for arching in solids
reduction factor for long-term creep
Name
allowable pressure
geotextile mass per unit area
height of the protrusion above the subgrade
actual pressure due to the cover system contents.
MFS MFPD MFA
Rounded:0.25
Max. Particle Size of
gravel in LCS =
RFCBD RFCR
Protrusion height:
Cushion GT
Mass per
Unit Area (g/m2)Harsh leachate
Water/Mild leachate
Moderate leachate
Safety Factor Against Geomembrane Puncture under Expanded Waste Height
(check a 10 oz./yd2 cushion geotextile)
Buncombe Co. Landfill
5/16/2017
1401-010
The actual cushion geotextile used in Cells 3 and 4, where the additional weigh of the expansion will be located is not known. The CQA
reports only refer to this material as a "heavy non-woven geotextile". Usually, geotextiles with a weight of 16 oz./yd2 or more are
considered "heavy". The geomembrane will be protected if the calculation shows that a thinner cushion, such as a 10 oz./yd2 non-woven,
provides sufficient cushion. Find the weight of the geotextile under the leachate collection gravel trench that will have an FOS > 1.0 against
puncture protection to the underlying geomembrane.
C:\Users\cmoeller\Documents\Buncombe LF Expansion\
LF Puncture Calculation v_0 v1_0.xlsx 2 of 3
Project:
Date:
Job#:
Buncombe Co. Landfill
5/16/2017
1401-010
Calculation of Pallow for 10 oz./yd2 geotextile
M =10 oz./yd2. =339
d =160.0 ft =48.77 m - maximum depth of material on top of geomembrane
γ =90 pcf =14.13 kN/m3 - Unit weight of waste on top of geomembrane - conservative
H =0.019 m - protrusion height - assume 1/2 maximum particle.
Modification and Reduction Factors:
MFS =0.75 (sub-rounded)
MFPD =0.83 (dense, 38 mm)
MFA =0.25 (geostatic, deep)
RFCR =2.0 (approx.19 mm protrusion with a 339 g/m2 geotextile - conservatively intrapolated)
RFCBD =1.5 (harsh leachate)
Pallow =1,007 kPa
Calculation of Pact
Max height of waste on gravel trench =48.8 m
Unit wt. of waste (assumed)=14.13 kN/m3
Pact = Unit weight of waste x Hwaste
Pact =14,400 psf =689.1 kPa
Calculation of FS
Long Term:FS =Pallow / Pact
FS =1.5 > 1.0, therefore OK!
CONCLUSION
References
g/m2 - Cushion Geotextile mass per unit area.
3. Koerner, R.M., Wilson-Fahmy, R.F. and Narejo, D. (1996), "Puncture Protection of Geomembranes Part III: Examples", Geosynthetics
International, Vol. 3, No. 5 pp. 655-675.
4. Koerner, R.M. (1998), Designing with Geosynthetics, Prentice Hall Publishing Co., Englewood Cliffs, NJ.
The geomembrane will be protected against puncture as long as the cushion is at least a 10 oz./yd2 non-woven geotextile installed under
the gravel in the leachate collection.
1. Wilson-Fahmy, R.F., Narejo, D. and Koerner, R.M. (1996), "Puncture Protection of Geomembranes Part I: Theory", Geosynthetics
International, Vol. 3, No. 5, pp. 605-628.
2. Narejo, D. and Koerner, R.M. and Wilson-Fahmy, R.F., (1996), "Puncture Protection of Geomembranes Part II: Experimental",
Geosynthetics International, Vol. 3, No. 5, pp. 629-653.
C:\Users\cmoeller\Documents\Buncombe LF Expansion\
LF Puncture Calculation v_0 v1_0.xlsx 3 of 3
Project:Date: Job#:Buncombe Co. Landfill5/16/20171401-010
2017 Facility Plan Modification
Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

III. BURIAL DESIGN OF LEACHATE COLLECTION PIPE

ANALYSIS OF THE STRUCTURAL INTEGRITY OF THE EXISTING HDPE
LEACHATE COLLECTION PIPES UNDER THE PROPOSED MAXIMUM
LOADS
HHNT analyzed the existing leachate collection pipes to assess whether the additional load resulting
from the vertical expansion would adversely affect the structural integrity of the pipes. Based on the
proposed landfill geometry, the maximum waste thickness over the existing 8-inch SDR 17 HDPE
leachate collection pipe in Cell 3 will be approximately 160 feet, and approximately 120 feet over the
exiting 10-inch SDR 17 HDPE pipe in Cell 4.
The analyses attached in this section considered the pipe diameters, the standard dimension ratio (SDR),
and burial conditions of the leachate collection system. This analysis assumes the actual loading on the
pipes is 75% of the total weight of the waste overlying the vertical projection of the pipes. The
reduction in stress distribution is based on the results of finite element modeling of typical waste mound
loadings on leachate pipe and leachate stone configurations. The analyses of the pipes under the
proposed waste and earthfill loads used stress analysis formulas for crushing, wall buckling and ring
deflection recommended on Chapters 3 and 6 of the Handbook of Polyethylene (PE) Pipe, published by
the Plastics Pipe Institute. The results of the evaluation indicate that the leachate collection pipes
constructed as shown on the Permit Drawings, will have satisfactory factors of safety against crushing,
buckling, and excessive ring deflection for the maximum proposed overburden and will therefore
continue to function as intended. It is noted that in the unlikelihood that one of the leachate collection
pipes fails under the maximum loads, leachate will continue to flow by gravity within the gravel
encasement around the leachate collection pipes towards the sumps. The stone protective cover layer
will also allow for lateral flow of leachate which provides additional redundancy.
C:\Users\cmoeller\Documents\Buncombe LF Expansion\
8 inch Pipe Strenght C 3 of Pipe Crushing.xlsx Page 1 of 4
Project:
Date:
Job#:
Structural Design of leachate collection pipe System Pipes
OBJECTIVE:
METHOD:
1. Determine the maximum vertical pressure acting on the leachate collection pipe .
2. Evaluate the pipe for:
a. Wall Crushing b. Wall Buckling c. Ring Deflection
PARAMETERS/INPUT: Max Height of Waste over Pipe 160 ft Unit weight of soil 120 pcf
Thickness of Final Cover 2.0 ft Unit wt. of waste (avg.)75 pcf (upper 100 feet)
90 pcf (below 100 feet)
Height of Gravel over pipe 2.0 ft Soil modulus (E' in psi) (Ref. 1)
Nom. Pipe Diameter 8.0 in Subgrade modulus (Ref. 1)
Perforation Diameter 0.375 in Ldl (Deflection Factor) =1 (Conservative)
# Perforations per foot 4 Kbed (Bedding Factor) =0.1 (Conservative)
1,000 psi Fs (soil support factor) =0.5 (Conservative)
Allow. Ring Deflection 7.5%
Outside Pipe Diameter 8.63 in
SDR 17
Min. Wall thickness 0.51 in
Internal Pipe Diameter =7.61 in
DM (Average Diameter of Pipe) =8.12 in
CALCULATIONS:
Computation of the vertical soil/waste pressure acting on pipe -
Vertical Pressure = Soil unit weight x (Hcover + Hgravel) + Unit weight of waste x HwasteVert. P =13,380 psf or 92.9 psi
PE = 0.75 Vert. P =69.7 psi
Check for Wall Crushing -
SA =SDR x Pprism =592.3 psi Where,
2 SA =Average Compressive Stress (psi)
Pprism =PE (conservative)
FS crush =1.7
Check for Wall Buckling -Where, B' = Soil Support Factor,
R = Buoyance Reduction Factor
=1.00E+00 =1.00 HGW = liquid height above pipe
H = Total cover height
=232.16 / FS psi: for Factor of Safety (N in equation) = 1
or 33,431 psf
PwcPprism
Compressive Strength of pipe (Ref. 1
- Table C-1 Chapt 3)
106,730 psi
(Assumes that arching occurs over the pipe as it deflects, thus the load
on the pipe is distributed over a larger area and the unit pressure is
=3.3FS buckling =
Elastic Mod. of HDPE (E) =
(long term , reduced for high
Buncombe Co. Landfill5/15/2017
1401-010
7,000 psi
Determine the structural durability of the existing 8-inch leachate collection pipe pipes in Cell 3 under the maximum height of waste.
3,500 psi
Elastic Mod. of HDPE (E) =
(short term)
23,809 psi
Comp. Strength/Sa =
C:\Users\cmoeller\Documents\Buncombe LF Expansion\
8 inch Pipe Strenght C 3 of Pipe Crushing.xlsx Page 2 of 4
Project:
Date:
Job#:
Structural Design of leachate collection pipe System Pipes
Buncombe Co. Landfill5/15/2017
1401-010
Check Ring Deflection -Where,
∆x / DM=Deflection (%)
Ring Deflection ==PL =Live Load (= 0 for this case)
and other variables are defined above.
∆x / DM=7.49%which is < than 7.50%, (p. 217, Chapter 6, Ref. 1) therefore above designed pipe is :SATISFACTORY
SUMMARY AND CONCLUSION:
The Factors of Safety calculated for the leachate collection pipe design are as follows:
Wall Crushing =1.7
Wall Buckling =3.3
The calculated max deflection is less than the maximum allowable deflection for plastic pipes (Ref.1).
REFERENCES:
Made by:CMM
Checked by: KB
Reviewed by:
Note that this analysis is for worst case high loading conditions in the center of the landfill. The loading on the leachate collection
pipes in the areas of the landfill closest to each outlet is significantly lower, and the FOS's under most of the landfill loading will be
higher than those reported above.
Ref. 2 - Assessment and Recommendations for Improving the Performance of Waste Containment Systems, EPA/600/R-02/099, 2002,
Page 2-24.
Ref. 1 - 2nd Edition, Handbook of Polyethylene (PE) Pipe, The Plastics Pipe Institute, Chapt. 3 and Chapt. 6
www.plasticpipe.org
C:\Users\cmoeller\Documents\Buncombe LF Expansion\
10 inch Pipe Strength C 4 of Pipe Crushing.xlsx Page 3 of 4
Project:
Date:
Job#:
Structural Design of leachate collection pipe System Pipes
OBJECTIVE:
METHOD:
1. Determine the maximum vertical pressure acting on the leachate collection pipe .
2. Evaluate the pipe for:
a. Wall Crushing b. Wall Buckling c. Ring Deflection
PARAMETERS/INPUT:
Max Height of Waste over Pipe 120 ft Unit weight of soil 120 pcf
Thickness of Final Cover 2.0 ft Unit wt. of waste (avg.)75 pcf (upper 100 feet)
90 pcf (below 100 feet)
Height of Gravel over pipe 2.0 ft Soil modulus (E' in psi) (Ref. 1)3,500 psi
Nom. Pipe Diameter 10.0 in Subgrade modulus (Ref. 1)7,000 psi
Perforation Diameter 0.375 in Ldl (Deflection Factor) =1 (Conservative)
# Perforations per foot 4 Kbed (Bedding Factor) =0.1 (Conservative)
1,000 psi Fs (soil support factor) =0.5 (Conservative)
Allow. Ring Deflection 7.5%
Outside Pipe Diameter 10.75 in
SDR 17
Min. Wall thickness 0.63 in
Internal Pipe Diameter =9.49 in
DM (Average Diameter of Pipe) =10.12 in
CALCULATIONS:
Computation of the vertical soil/waste pressure acting on pipe -
Vertical Pressure = Soil unit weight x (Hcover + Hgravel) + Unit weight of waste x HwasteVert. P =9,780 psf or 67.9 psi
PE = 0.75 Vert. P =50.9 psi
Check for Wall Crushing -
SA =SDR x Pprism =433.0 psi Where,
2 SA =Average Compressive Stress (psi)
Pprism =PE (conservative)
FS crush =2.3
Check for Wall Buckling -Where, B' = Soil Support Factor,
R = Buoyance Reduction Factor
=9.99E-01 =0.99 HGW = liquid height above pipe
H = Total cover height
=231.87 / FS psi: for Factor of Safety (N in equation) = 1
or 33,390 psf
FS buckling =Pwc =4.6
Pprism
Buncombe Co. Landfill
5/15/2017
1401-010
Elastic Mod. of HDPE (E) =
(long term , reduced for high
temperature)
Determine the structural durability of the existing 10-inch leachate collection pipe pipes in Cell 4 under the maximum height of
waste.
23,809 psi
Compressive strength of pipe (Ref. 1
- Table C-1 Chapt. 3)
106,730 psiElastic Mod. of HDPE (E) =
(short term)
(Assumes that arching occurs over the pipe as it deflects, thus the load
on the pipe is distributed over a larger area and the unit pressure is
reduced - Ref. 2)
Comp. Strength/Sa =
C:\Users\cmoeller\Documents\Buncombe LF Expansion\
10 inch Pipe Strength C 4 of Pipe Crushing.xlsx Page 4 of 4
Project:
Date:
Job#:
Structural Design of leachate collection pipe System Pipes
Buncombe Co. Landfill
5/15/2017
1401-010
Check Ring Deflection -Where,
∆x / DM=Deflection (%)
Ring Deflection ==PL =Live Load (= 0 for this case)
and other variables are defined above.
∆x / DM=5.47%which is < than 7.50%, (p. 217, Chapter 6, Ref. 1) therefore above designed pipe is :SATISFACTORY
SUMMARY AND CONCLUSION:
The Factors of Safety calculated for the leachate collection pipe design are as follows:
Wall Crushing =2.3
Wall Buckling =4.6
The calculated max deflection is less than the maximum allowable deflection for plastic pipes (Ref.1).
REFERENCES:
Made by:CMM
Checked by: KB
Reviewed by:
Ref. 2 - Assessment and Recommendations for Improving the Performance of Waste Containment Systems, EPA/600/R-02/099,
2002, Page 2-24.
Ref. 1 - 2nd Edition, Handbook of Polyethylene (PE) Pipe, The Plastics Pipe Institute, Chapt.. 3 and Chapt.. 6
http://plasticpipe.org/publications/pe-handbook.html
Note that this analysis is for worst case high loading conditions in the center of the landfill. The loading on the leachate
collection pipes in the areas of the landfill closest to each outlet is significantly lower, and the FOS's under most of the landfill
loading will be higher than those reported above.
2017 Facility Plan Modification
Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

IV. SLOPE STABILITY EVALUATION

2017 Facility Plan Modification
Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

STABILITY ANALYSES FOR EXPANDED CELLS
HHNT conducted global slope stability evaluations using the computer software program GSLOPE
version 5.13 (Mitre Software Corporation, 2012) which uses both Bishop’s and Jambu’s generalized limit
equilibrium methods to search for the failure surface that produces the lowest factor of safety (FOS).
The Jambu Method of circular failure search mode was used to locate failure planes with low factors of
safety for the analyses of the Buncombe Landfill Expansion. Two analysis cross-sections (labeled AA and
BB) were selected as worst case conditions and are detailed in the analyses included in this section.
Note that failure planes through the landfill foundation soil/rock were excluded from the stability
searches to focus the analyses on block failures along the geosynthetic liner/leachate collection systems.
The stability analyses conducted by CDM Smith for the Phase IV (Cell 7) Permit to Construct Application
(2014 CDM Smith Application) indicate that block failures along the geosynthetic/soil interface are the
most critical and will have the lowest factors of safety.

HHNT assumed that the constructed liner and leachate collection systems are similar to the one that
was designed and permitted for Cell 7. This assumption was made based on a discussion in Section 1.1
of the Engineering Design Section of the 2014 CDM Smith Application, which states that “…. the design is
consistent with the original permitted design.” Thus, the material properties used for the analyses
included in this application are the same as the material properties included in Appendix 3B of the 2014
CDM Smith Application. The cross-sections analyzed were simplified to consist of only two layers, i.e.
the waste and the underlying geosynthetic/soil interface with the following parameters (refer to the
2014 CDM Smith Application for a full discussion on how these were selected):

The factors of safety (FOS) calculated for the cross-sections analyzed and using the parameters listed
above exceeded 1.6 for static conditions. The results of the analyses are included in this section.

HHNT also conducted a deformation analysis based upon EPA’s guidance document “Seismic Design
Guidance for Municipal Solid Waste Landfill Facilities” dated April 1995. As in the 2014 CDM Smith
Application, the deformation analyses were done using four (4) inches of displacement across the liner
system as the limiting criteria under seismic loading conditions. In order to estimate the displacements,
the yield acceleration (ky) that results in a factor of safety of 1.0 was determined for each of the cases
analyzed. The peak ground acceleration (PGA) for the site was previously determined to be 0.226g for

Material
Design Strength
Parameters
Unit Weight
(pcf)
Waste φ’ = 27.5 deg. c' = 0 psf 90
Geosynthetic Interface φ’ = 23 c' = 0 psf 110
2017 Facility Plan Modification
Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

an earthquake with a 2% probability of exceedance in 50 years, according to the U.S. Geological Survey
(USGS) Probabilistic Seismic Hazard Disaggregation 2chart for this site.

The ratio between the yield acceleration and the PGA of a failure mass is used to estimate the potential
maximum displacements from design charts included in EPA’s guidance document and other technical
sources. For consistency with prior analyses, HHNT used the Makdisi and Seed, 1978 chart to estimate
potential displacements for each of the sections analyzed.

The results of the analyses indicate that the computed displacements are less than one (1) inches for all
cases. The seismic deformation analyses, reference material, and graphical output are included in this
section for reference.

Summary and Conclusion

The results of the stability analyses are summarized in the Table below:

Cross
Section
Stability Analyses Results
Static FOS Seismic Analysis
Est. Displacement (in)
Section A-A Left (South) 1.63 0.83
Section A-A Left (North) 1.66 0.47
Section B-B (East) 1.62 0.71

The factors of safety (FOS) calculated for all cross-sections analyzed are greater than the minimum
required of 1.5 for static conditions, and the potential seismic displacement are lower than the design
requirement of four (4) inches. Based on the analyses discussed above, the vertical expansion of the
Buncombe Landfill will not compromise the overall stability of the existing cells 1 through 6.

2 https://geohazards.usgs.gov/deaggint/2008/

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HHNT - Macon, GA 1401-010 Buncombe County LF Expansion 5/12/2017 Section A-A - Left Static
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LIMIT EQUILIBRIUM SLOPE STABILITY ANALYSIS GSLOPE analysis run by:- HHNT - Macon, GA 9Q6340W Results are for Janbu's Simplified Method unless otherwise noted. File C:\Users\cmoeller\Documents\Buncombe LF Expansion\Stability\A-A Left Static.gsl Output dated 05-16-2017 at 13:41:39 Material Unit Wt Cohesion Friction Min. Piezo Ru Interaction Angle c/p Surf. Coefficient 1 Waste 90 0 27.5 0 0 0 0 2 Liner Interface 110 0 23 0 0 0 0 3 Slide Surface -1 0 0 0 0 0 0 X-centre Y-centre Radius Factor Iterations Slices M Alpha of Safety Warnings -61 3112 1207 1.6281 4 18 0 ------------------------------------------------------------------------------- DETAILED SLICE PRINTOUT Intersection points of Slip Surface with Material Surfaces:- X Y -353.588 1941 667.975 2150 -353.588 1941 466.294 2026.27 -353.588 1941 463.645 2024.987 Slice No X-Coord Y-Coord MATERIAL Edge 255 2017.5 1 Mid-Base 255.29 2017.41 # 2 (Liner Interface) Edge 255.58 2017.319 2 Mid-Base 264.26 2014.615 # 2 (Liner Interface) Edge 272.94 2011.91 3 Mid-Base 281.62 2009.205 # 2 (Liner Interface) Edge 290.3 2006.5 4 Mid-Base 304.745 2008.041 # 2 (Liner Interface) Edge 319.190 2009.581 5 Mid-Base 333.636 2011.122 # 2 (Liner Interface)
Edge 348.081 2012.662 6 Mid-Base 362.527 2014.203 # 2 (Liner Interface) Edge 376.972 2015.744 7 Mid-Base 391.417 2017.284 # 2 (Liner Interface) Edge 405.863 2018.825 8 Mid-Base 420.308 2020.365 # 2 (Liner Interface) Edge 434.754 2021.906 9 Mid-Base 449.199 2023.447 # 2 (Liner Interface) Edge 463.645 2024.987 10 Mid-Base 464.969 2025.628 # 2 (Liner Interface) Edge 466.294 2026.27 11 Mid-Base 482.070 2034.074 # 1 (Waste) Edge 497.847 2042.169 12 Mid-Base 513.623 2050.559 # 1 (Waste) Edge 529.4 2059.253 13 Mid-Base 543.04 2067.019 # 1 (Waste) Edge 556.68 2075.023 14 Mid-Base 570.319 2083.271 # 1 (Waste) Edge 583.96 2091.767 15 Mid-Base 597.6 2100.518 # 1 (Waste) Edge 611.239 2109.532 16 Mid-Base 624.879 2118.814 # 1 (Waste) Edge 638.519 2128.374 17 Mid-Base 652.159 2138.218 # 1 (Waste) Edge 665.8 2148.355 18 Mid-Base 666.887 2149.177 # 1 (Waste) Edge 667.975 2150 Water force on right side = 0 at Y= 2150 Water force on left side = 0 at Y= 2017.5 First slice No. = 1 Last Slice No. = 18
There are no explicit external forces in the data set. Reinforcement Tallowable Tconnection Layer Position per unit per unit No. X1 Length Elevation width width Reinf. Soil X-Coord of Total Pore Force used Layer Mat'l Slip surface Vertical Pressure per unit No. No. Intersection Stress width Slice Width Vertical Pore Tan Alpha Tan Phi Weight TL(I) No. Stress Pressure
1 .580 9.93 0 .31169 .42447 5.76 -2326.17 2 17.36 519.72 0 .31160 .42447 9022.47 -3641895 3 17.359 1519.44 0 .31161 .42447 26377.6 -10647190 4 28.890 2300.58 0 -.10664 .42447 66465.86 -32064750 5 28.890 2863.10 0 -.10664 .42447 82717.59 -39904980 6 28.890 3425.66 0 -.10665 .42447 98970.27 -47745720 7 28.890 3988.19 0 -.10664 .42447 115222.3 -55586060 8 28.890 4550.74 0 -.10664 .42447 131474.7 -63426590 9 28.890 5113.28 0 -.10665 .42447 147726.7 -71267090 10 2.649 5365.44 0 -.48412 .42447 14213.32 -7282069 11 31.553 5092.31 0 -.50387 .52056 160677.9 -100957900 12 31.553 4525.95 0 -.54143 .52056 142807.3 -89729340 13 27.279 3899.66 0 -.57810 .52056 106382.7 -66842840 14 27.279 3230.06 0 -.61376 .52056 88116.16 -55365540 15 27.279 2470.80 0 -.65120 .52056 67403.43 -42351220 16 27.279 1617.18 0 -.69068 .52056 44116.82 -27719680 17 27.280 663.88 0 -.73247 .52056 18110.76 -11379430 18 2.175 74.09 0 -.75600 .52056 161.17 -101267.9 SLICE MALPHA DELTANUM N.FORCE N.LEVER RADIUS DEL.PF Cohesion 1 .87711 -2652.0 6.5 -627.68 -950.88 -4124.30 0 2 .87715 -4151918 10286.0 -637.00 -950.93 -6552249 0 3 .87715 -12138310 30071.7 -655.19 -950.92 -19702860 0 4 1.02200 -31374240 65034.5 -246.61 -1136.52 -16038220 0 5 1.02200 -39045620 80936.2 -275.66 -1136.52 -22311330 0 6 1.02201 -46717490 96838.8 -304.71 -1136.52 -29508300 0 7 1.02200 -54389010 112741 -333.77 -1136.52 -37630110 0 8 1.02200 -62060690 128643.4 -362.82 -1136.52 -46675620 0 9 1.02201 -69732300 144545.3 -391.87 -1136.52 -56644310 0 10 1.01367 -7183837 14021.5 0 -1207 0 0 11 1.03691 -97364030 154958.2 0 -1207 0 0 12 1.03161 -86979930 138431.6 0 -1207 0 0 13 1.02576 -65163900 103710.6 0 -1207 0 0 14 1.01952 -54305230 86428.6 0 -1207 0 0 15 1.01245 -41830070 66573.9 0 -1207 0 0 16 1.00452 -27594860 43918.1 0 -1207 0 0 17 .99566 -11428920 18189.5 0 -1207 0 0 18 .99051 -102237.8 162.7 0 -1207 0 0 ---------------------------------------------------------------------------- NUM = -7.115652E+08 PF = -2.350671E+08 PF is Total Moment due to Normal forces SWX = -6.859906E+08 FACTOR OF SAFETY = 1.578018 Bishop Factor of Safety = NUM! /(SWX + EQM + GridMoment - PF!) Weight Moment = -6.859906E+08 Water Moments = 0 Ext.Force Moment = 0 ----------- SWX = -6.859906E+08 0 is the moment due to the horizontal components of the active external forces, along with a minor adjustment for non-coincidence of the force locations with the centrelines of the slices they act on. The vertical components are treated as part of the slice weight. Geogrid Moment = 0 Earthquake Moment EQM = 0
NUM is Total of (TL(ie Top Line)/MALPHA) for all slices) Malpha values shown are for final iteration. TL for any slice is given by :- Radius ( Width ( Cohesion + Tan Fy (Vertical Stress - Pore pressure))) No. of slices used in analysis = 18 NUMJ= 657925.9 WTANALPHA= -425997.7 WEIGHT= 1319973 FLAGRI=-1 HFORCE= 0 SEISMIC= 0 HForceGrids = 0 (NUMJ*FLAGRI) Unfactored Janbu FoS = --------------------- WTANALPHA+WEIGHT*SEISMIC*FLAGRI+WFL-WFR-HFORCE-HForcegrids*FLAGRI
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HHNT - Macon, GA 1401-010 Buncombe County LF Expansion 5/12/2017 Section A-A - Right Static
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LIMIT EQUILIBRIUM SLOPE STABILITY ANALYSIS GSLOPE analysis run by:- HHNT - Macon, GA 9Q6340W Results are for Janbu's Simplified Method unless otherwise noted. File C:\Users\cmoeller\Documents\Buncombe LF Expansion\Stability\A-A Right Static.gsl Output dated 05-15-2017 at 13:19:52 Material Unit Wt Cohesion Friction Min. Piezo Ru Interaction Angle c/p Surf. Coefficient 1 Waste 90 0 27.5 0 0 0 0 2 Liner Interface 110 0 23 0 0 0 0 3 Slide Surface -1 0 0 0 0 0 0 X-centre Y-centre Radius Factor Iterations Slices M Alpha of Safety Warnings 1425 3180 1240 1.656 4 60 0 ------------------------------------------------------------------------------- DETAILED SLICE PRINTOUT Intersection points of Slip Surface with Material Surfaces:- X Y 734.565 2150 1815.219 2003 1061.675 1994.422 1815.219 2003 1065.005 1993.407 1815.219 2003 Slice No X-Coord Y-Coord MATERIAL Edge 734.565 2150 1 Mid-Base 734.687 2149.918 # 1 (Waste) Edge 734.81 2149.836 2 Mid-Base 738.796 2147.177 # 1 (Waste) Edge 742.782 2144.539 3 Mid-Base 746.768 2141.924 # 1 (Waste) Edge 750.754 2139.331
4 Mid-Base 754.740 2136.759 # 1 (Waste) Edge 758.726 2134.208 5 Mid-Base 762.713 2131.679 # 1 (Waste) Edge 766.699 2129.172 6 Mid-Base 770.685 2126.685 # 1 (Waste)
Edge 774.671 2124.219 7 Mid-Base 778.657 2121.774 # 1 (Waste) Edge 782.643 2119.35 8 Mid-Base 786.629 2116.946 # 1 (Waste) Edge 790.616 2114.563 9 Mid-Base 794.602 2112.199 # 1 (Waste) Edge 798.588 2109.856 10 Mid-Base 802.574 2107.532 # 1 (Waste) Edge 806.560 2105.229 11 Mid-Base 810.546 2102.945 # 1 (Waste) Edge 814.532 2100.681 12 Mid-Base 818.519 2098.436 # 1 (Waste) Edge 822.505 2096.21 13 Mid-Base 826.491 2094.004 # 1 (Waste) Edge 830.477 2091.817 14 Mid-Base 834.463 2089.648 # 1 (Waste) Edge 838.449 2087.499 15 Mid-Base 842.435 2085.368 # 1 (Waste) Edge 846.422 2083.256 16 Mid-Base 850.408 2081.162 # 1 (Waste) Edge 854.394 2079.087 17 Mid-Base 858.380 2077.03 # 1 (Waste) Edge 862.366 2074.991 18 Mid-Base 866.352 2072.971 # 1 (Waste) Edge 870.338 2070.969 19 Mid-Base 874.325 2068.984 # 1 (Waste) Edge 878.311 2067.017 20 Mid-Base 882.297 2065.068 # 1 (Waste) Edge 886.283 2063.136 21 Mid-Base 890.269 2061.222 # 1 (Waste)
Edge 894.255 2059.326 22 Mid-Base 898.241 2057.447 # 1 (Waste) Edge 902.228 2055.585 23 Mid-Base 906.214 2053.74 # 1 (Waste) Edge 910.200 2051.913 24 Mid-Base 914.186 2050.102 # 1 (Waste) Edge 918.172 2048.308 25 Mid-Base 922.158 2046.531 # 1 (Waste) Edge 926.145 2044.771 26 Mid-Base 930.131 2043.028 # 1 (Waste) Edge 934.117 2041.302 27 Mid-Base 938.103 2039.591 # 1 (Waste)
Edge 942.089 2037.898 28 Mid-Base 946.075 2036.22 # 1 (Waste) Edge 950.061 2034.56 29 Mid-Base 954.048 2032.915 # 1 (Waste) Edge 958.034 2031.286 30 Mid-Base 962.020 2029.674 # 1 (Waste) Edge 966.006 2028.078 31 Mid-Base 969.992 2026.497 # 1 (Waste) Edge 973.978 2024.933 32 Mid-Base 977.964 2023.384 # 1 (Waste) Edge 981.951 2021.852 33 Mid-Base 985.937 2020.335 # 1 (Waste) Edge 989.923 2018.833 34 Mid-Base 993.909 2017.347 # 1 (Waste) Edge 997.895 2015.877 35 Mid-Base 1001.882 2014.422 # 1 (Waste) Edge 1005.868 2012.983 36 Mid-Base 1009.854 2011.559 # 1 (Waste) Edge 1013.84 2010.151 37 Mid-Base 1017.826 2008.757 # 1 (Waste) Edge 1021.812 2007.379 38 Mid-Base 1025.799 2006.016 # 1 (Waste) Edge 1029.785 2004.668 39 Mid-Base 1033.771 2003.335 # 1 (Waste) Edge 1037.757 2002.017 40 Mid-Base 1041.743 2000.715 # 1 (Waste) Edge 1045.729 1999.427 41 Mid-Base 1049.716 1998.153 # 1 (Waste) Edge 1053.702 1996.895 42 Mid-Base 1057.688 1995.651 # 1 (Waste)
Edge 1061.675 1994.422 43 Mid-Base 1063.34 1993.913 # 2 (Liner Interface) Edge 1065.005 1993.407 44 Mid-Base 1068.702 1993.39 # 2 (Liner Interface) Edge 1072.4 1993.373 45 Mid-Base 1076.098 1993.356 # 2 (Liner Interface) Edge 1079.796 1993.339 46 Mid-Base 1083.493 1993.322 # 2 (Liner Interface) Edge 1087.191 1993.305 47 Mid-Base 1090.889 1993.288 # 2 (Liner Interface) Edge 1094.586 1993.271 48 Mid-Base 1098.284 1993.254 # 2 (Liner Interface)
Edge 1101.982 1993.237 49 Mid-Base 1105.679 1993.22 # 2 (Liner Interface) Edge 1109.377 1993.203 50 Mid-Base 1113.075 1993.186 # 2 (Liner Interface) Edge 1116.772 1993.169 51 Mid-Base 1120.47 1993.153 # 2 (Liner Interface) Edge 1124.168 1993.136 52 Mid-Base 1127.865 1993.119 # 2 (Liner Interface) Edge 1131.563 1993.102 53 Mid-Base 1135.261 1993.085 # 2 (Liner Interface) Edge 1138.959 1993.068 54 Mid-Base 1142.656 1993.051 # 2 (Liner Interface) Edge 1146.354 1993.034 55 Mid-Base 1150.052 1993.017 # 2 (Liner Interface) Edge 1153.75 1993 56 Mid-Base 1157.344 1994.29 # 2 (Liner Interface) Edge 1160.938 1995.58 57 Mid-Base 1164.531 1996.87 # 2 (Liner Interface) Edge 1168.125 1998.16 58 Mid-Base 1171.719 1999.45 # 2 (Liner Interface) Edge 1175.313 2000.74 59 Mid-Base 1178.906 2002.031 # 2 (Liner Interface) Edge 1182.5 2003.321 60 Mid-Base 1182.75 2003.41 # 2 (Liner Interface) Edge 1183 2003.5 Water force on right side = 0 at Y= 2003.5 Water force on left side = 0 at Y= 2150 First slice No. = 1 Last Slice No. = 60 There are no explicit external forces in the data set.
Reinforcement Tallowable Tconnection Layer Position per unit per unit No. X1 Length Elevation width width Reinf. Soil X-Coord of Total Pore Force used Layer Mat'l Slip surface Vertical Pressure per unit No. No. Intersection Stress width Slice Width Vertical Pore Tan Alpha Tan Phi Weight TL(I) No. Stress Pressure 1 .244 7.38 0 .67065 .52056 1.80 1165.81 2 7.972 136.71 0 .66438 .52056 1089.92 703548.5 3 7.972 374.67 0 .65335 .52056 2987.04 1928144
4 7.972 604.75 0 .64248 .52056 4821.27 3112145 5 7.972 827.07 0 .63176 .52056 6593.66 4256231 6 7.972 1041.76 0 .62123 .52056 8305.27 5361080 7 7.972 1248.92 0 .61075 .52056 9956.79 6427145 8 7.972 1448.70 0 .60052 .52056 11549.47 7455217 9 7.972 1641.11 0 .59036 .52056 13083.45 8445409 10 7.972 1826.34 0 .58037 .52056 14560.15 9398625 11 7.972 2004.41 0 .57048 .52056 15979.75 10314980 12 7.972 2175.42 0 .56074 .52056 17343.12 11195040 13 7.972 2339.51 0 .55113 .52056 18651.3 12039480 14 7.972 2496.73 0 .54160 .52056 19904.66 12848520 15 7.972 2647.15 0 .53220 .52056 21103.89 13622630 16 7.972 2790.87 0 .52289 .52056 22249.7 14362250 17 7.972 2927.98 0 .51374 .52056 23342.77 15067830 18 7.972 3058.52 0 .50461 .52056 24383.47 15739610 19 7.972 3182.58 0 .49567 .52056 25372.49 16378030 20 7.972 3300.20 0 .48676 .52056 26310.19 16983310 21 7.972 3411.51 0 .47794 .52056 27197.62 17556150 22 7.972 3516.52 0 .46927 .52056 28034.76 18096530 23 7.972 3615.31 0 .46061 .52056 28822.34 18604910 24 7.972 3707.97 0 .45209 .52056 29561.04 19081750 25 7.972 3794.52 0 .44364 .52056 30251.04 19527150 26 7.972 3875.02 0 .43525 .52056 30892.79 19941390 27 7.972 3949.53 0 .42693 .52056 31486.8 20324830 28 7.972 4018.14 0 .41873 .52056 32033.78 20677900 29 7.972 4080.83 0 .41057 .52056 32533.63 21000560 30 7.972 4137.71 0 .40247 .52056 32987.06 21293250 31 7.972 4188.83 0 .39446 .52056 33394.6 21556320 32 7.972 4234.20 0 .38650 .52056 33756.34 21789820 33 7.972 4273.89 0 .37861 .52056 34072.7 21994030 34 7.972 4307.93 0 .37079 .52056 34344.13 22169240 35 7.972 4336.40 0 .36301 .52056 34571.06 22315730 36 7.972 4359.29 0 .35529 .52056 34753.59 22433550 37 7.972 4376.7 0 .34763 .52056 34892.32 22523100 38 7.972 4388.59 0 .34004 .52056 34987.45 22584510 39 7.972 4395.06 0 .33249 .52056 35038.77 22617630 40 7.972 4396.13 0 .32499 .52056 35047.27 22623120 41 7.972 4391.85 0 .31755 .52056 35013.11 22601070 42 7.973 4382.24 0 .31012 .52056 34941.37 22554770 43 3.329 4382.24 0 .30494 .42447 14591.6 7680269 44 7.395 4281.37 0 .00457 .42447 31662.43 15969660 45 7.395 4066.63 0 .00458 .42447 30074.36 15168750 46 7.395 3851.87 0 .00458 .42447 28486.12 14367680 47 7.395 3637.13 0 .00458 .42447 26898.04 13566690 48 7.395 3422.37 0 .00457 .42447 25309.8 12765570
49 7.395 3207.62 0 .00458 .42447 23721.65 11964600 50 7.395 2992.87 0 .00458 .42447 22133.49 11163570 51 7.395 2778.11 0 .00457 .42447 20545.25 10362460 52 7.395 2563.37 0 .00458 .42447 18957.18 9561518 53 7.395 2348.61 0 .00458 .42447 17368.94 8760451 54 7.395 2133.87 0 .00457 .42447 15780.86 7959437 55 7.395 1919.10 0 .00458 .42447 14193.71 7158948 56 7.187 1587.72 0 -.35896 .42447 11411.74 4967789 57 7.187 1139.73 0 -.35898 .42447 8191.86 3566072 58 7.187 691.74 0 -.35896 .42447 4971.89 2164379 59 7.187 243.73 0 -.35898 .42447 1751.84 762612.3 60 .5 9.86 0 -.35888 .42447 4.93 2148.27 SLICE MALPHA DELTANUM N.FORCE N.LEVER RADIUS DEL.PF Cohesion 1 1.00532 1159.6 1.7 0 1240 0 0 2 1.00660 698933.6 1082.7 0 1240 0 0 3 1.00881 1911291 2960.9 0 1240 0 0
4 1.01096 3078393 4768.9 0 1240 0 0 5 1.01304 4201433 6508.7 0 1240 0 0 6 1.01504 5281607 8182.1 0 1240 0 0 7 1.017 6319708 9790.3 0 1240 0 0 8 1.01886 7317157 11335.5 0 1240 0 0 9 1.02068 8274264 12818.3 0 1240 0 0 10 1.02242 9192471 14240.7 0 1240 0 0 11 1.02411 10072130 15603.5 0 1240 0 0 12 1.02572 10914240 16908.1 0 1240 0 0 13 1.02728 11719740 18155.9 0 1240 0 0 14 1.02877 12489100 19347.8 0 1240 0 0 15 1.03021 13223120 20484.9 0 1240 0 0 16 1.03159 13922450 21568.3 0 1240 0 0 17 1.0329 14587900 22599.2 0 1240 0 0 18 1.03416 15219690 23578.0 0 1240 0 0 19 1.03535 15818790 24506.1 0 1240 0 0 20 1.03649 16385320 25383.7 0 1240 0 0 21 1.03758 16920250 26212.5 0 1240 0 0 22 1.03860 17423900 26992.7 0 1240 0 0 23 1.03958 17896560 27724.9 0 1240 0 0 24 1.04049 18339130 28410.5 0 1240 0 0 25 1.04135 18751680 29049.7 0 1240 0 0 26 1.04216 19134610 29642.9 0 1240 0 0 27 1.04291 19488420 30191.0 0 1240 0 0 28 1.04361 19813690 30694.9 0 1240 0 0 29 1.04426 20110360 31154.5 0 1240 0 0 30 1.04486 20379000 31570.7 0 1240 0 0 31 1.04540 20620060 31944.1 0 1240 0 0 32 1.04589 20833590 32274.9 0 1240 0 0 33 1.04634 21019960 32563.6 0 1240 0 0 34 1.04673 21179500 32810.8 0 1240 0 0 35 1.04707 21312490 33016.8 0 1240 0 0 36 1.04736 21419060 33181.9 0 1240 0 0 37 1.04760 21499600 33306.7 0 1240 0 0 38 1.04779 21554240 33391.3 0 1240 0 0 39 1.04794 21582890 33435.7 0 1240 0 0 40 1.04803 21586150 33440.8 0 1240 0 0 41 1.04808 21564130 33406.7 0 1240 0 0 42 1.04808 21519950 33338.2 0 1240 0 0 43 1.03116 7448187 14150.6 0 1240 0 0 44 1.00116 15951160 31625.7 350.86 1188.22 11096480 0 45 1.00116 15151110 30039.4 343.45 1188.23 10317130 0 46 1.00116 14350980 28453 336.05 1188.23 9561856 0 47 1.00116 13550920 26866.7 328.66 1188.23 8830095 0 48 1.00116 12750790 25280.4 321.28 1188.22 8122282 0
49 1.00116 11950690 23694.0 313.87 1188.23 7436890 0 50 1.00116 11150590 22107.7 306.47 1188.23 6775498 0 51 1.00116 10350460 20521.4 299.1 1188.22 6137969 0 52 1.00116 9550403 18935.1 291.68 1188.23 5523098 0 53 1.00116 8750267 17348.7 284.28 1188.23 4932066 0 54 1.00116 7950218 15762.5 276.91 1188.22 4364877 0 55 1.00116 7150627 14177.2 269.49 1188.23 3820743 0 56 .85473 5812079 13351.1 652.51 1025.55 8711919 0 57 .85472 4172179 9584.1 644.89 1025.54 6180834 0 58 .85473 2532222 5816.8 637.24 1025.55 3706790 0 59 .85472 892229.5 2049.6 629.62 1025.54 1290481 0 60 .85477 2513.2 5.7 625.45 1025.60 3610.78 0 ---------------------------------------------------------------------------- NUM = 7.840458E+08 PF = 1.068126E+08 PF is Total Moment due to Normal forces SWX = 5.925574E+08 FACTOR OF SAFETY = 1.61411
Bishop Factor of Safety = NUM! /(SWX + EQM + GridMoment - PF!) Weight Moment = 5.925574E+08 Water Moments = 0 Ext.Force Moment = 0 ----------- SWX = 5.925574E+08 0 is the moment due to the horizontal components of the active external forces, along with a minor adjustment for non-coincidence of the force locations with the centrelines of the slices they act on. The vertical components are treated as part of the slice weight. Geogrid Moment = 0 Earthquake Moment EQM = 0 NUM is Total of (TL(ie Top Line)/MALPHA) for all slices) Malpha values shown are for final iteration. TL for any slice is given by :- Radius ( Width ( Cohesion + Tan Fy (Vertical Stress - Pore pressure))) No. of slices used in analysis = 60 NUMJ= 684200.4 WTANALPHA= 431923.4 WEIGHT= 1322259 FLAGRI= 1 HFORCE= 0 SEISMIC= 0 HForceGrids = 0 (NUMJ*FLAGRI) Unfactored Janbu FoS = --------------------- WTANALPHA+WEIGHT*SEISMIC*FLAGRI+WFL-WFR-HFORCE-HForcegrids*FLAGRI Unf. Janbu FoS = 1.584078
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HHNT - Macon, GA 1401-010 Buncombe County LF Expansion 5/12/2017 Section B-B - Left Static
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LIMIT EQUILIBRIUM SLOPE STABILITY ANALYSIS GSLOPE analysis run by:- HHNT - Macon, GA 9Q6340W Results are for Janbu's Simplified Method unless otherwise noted. File C:\Users\cmoeller\Documents\Buncombe LF Expansion\Stability\B-B Left.gsl Output dated 05-15-2017 at 14:23:55 Material Unit Wt Cohesion Friction Min. Piezo Ru Interaction Angle c/p Surf. Coefficient 1 Waste 90 0 27.5 0 0 0 0 2 Liner Interface 110 0 23 0 0 0 0 3 Slide Surface -1 0 0 0 0 0 0 X-centre Y-centre Radius Factor Iterations Slices M Alpha of Safety Warnings 222.9 2538.79 583.79 1.622 4 140 0 ------------------------------------------------------------------------------- DETAILED SLICE PRINTOUT Intersection points of Slip Surface with Material Surfaces:- X Y 62.386 1977.5 658.396 2150 62.386 1977.5 468.666 2009.252 62.386 1977.5 465.540 2007.812 Slice No X-Coord Y-Coord MATERIAL Edge 113.5 1977.5 1 Mid-Base 113.75 1977.417 # 2 (Liner Interface) Edge 114 1977.333 2 Mid-Base 114.07 1977.31 # 2 (Liner Interface) Edge 114.14 1977.287 3 Mid-Base 116.133 1976.622 # 2 (Liner Interface) Edge 118.126 1975.958
4 Mid-Base 120.119 1975.294 # 2 (Liner Interface) Edge 122.112 1974.629 5 Mid-Base 124.105 1973.965 # 2 (Liner Interface) Edge 126.098 1973.301 6 Mid-Base 128.091 1972.636 # 2 (Liner Interface)
Edge 130.084 1971.972 7 Mid-Base 132.077 1971.308 # 2 (Liner Interface) Edge 134.07 1970.643 8 Mid-Base 136.063 1969.979 # 2 (Liner Interface) Edge 138.056 1969.315 9 Mid-Base 140.049 1968.65 # 2 (Liner Interface) Edge 142.042 1967.986 10 Mid-Base 144.035 1967.322 # 2 (Liner Interface) Edge 146.028 1966.657 11 Mid-Base 148.021 1965.993 # 2 (Liner Interface) Edge 150.014 1965.329 12 Mid-Base 152.007 1964.664 # 2 (Liner Interface) Edge 154 1964 13 Mid-Base 155.997 1964.281 # 2 (Liner Interface) Edge 157.994 1964.562 14 Mid-Base 159.991 1964.843 # 2 (Liner Interface) Edge 161.988 1965.123 15 Mid-Base 163.985 1965.404 # 2 (Liner Interface) Edge 165.982 1965.685 16 Mid-Base 167.979 1965.966 # 2 (Liner Interface) Edge 169.976 1966.247 17 Mid-Base 171.973 1966.528 # 2 (Liner Interface) Edge 173.970 1966.808 18 Mid-Base 175.967 1967.089 # 2 (Liner Interface) Edge 177.964 1967.37 19 Mid-Base 179.961 1967.651 # 2 (Liner Interface) Edge 181.958 1967.932 20 Mid-Base 183.955 1968.213 # 2 (Liner Interface) Edge 185.952 1968.494 21 Mid-Base 187.949 1968.774 # 2 (Liner Interface)
Edge 189.947 1969.055 22 Mid-Base 191.944 1969.336 # 2 (Liner Interface) Edge 193.941 1969.617 23 Mid-Base 195.938 1969.898 # 2 (Liner Interface) Edge 197.935 1970.179 24 Mid-Base 199.932 1970.459 # 2 (Liner Interface) Edge 201.929 1970.74 25 Mid-Base 203.926 1971.021 # 2 (Liner Interface) Edge 205.923 1971.302 26 Mid-Base 207.920 1971.583 # 2 (Liner Interface) Edge 209.917 1971.864 27 Mid-Base 211.914 1972.145 # 2 (Liner Interface)
Edge 213.911 1972.425 28 Mid-Base 215.908 1972.706 # 2 (Liner Interface) Edge 217.905 1972.987 29 Mid-Base 219.902 1973.268 # 2 (Liner Interface) Edge 221.899 1973.549 30 Mid-Base 223.896 1973.83 # 2 (Liner Interface) Edge 225.894 1974.11 31 Mid-Base 227.891 1974.391 # 2 (Liner Interface) Edge 229.888 1974.672 32 Mid-Base 231.885 1974.953 # 2 (Liner Interface) Edge 233.882 1975.234 33 Mid-Base 235.879 1975.515 # 2 (Liner Interface) Edge 237.876 1975.796 34 Mid-Base 239.873 1976.076 # 2 (Liner Interface) Edge 241.870 1976.357 35 Mid-Base 243.867 1976.638 # 2 (Liner Interface) Edge 245.864 1976.919 36 Mid-Base 247.861 1977.2 # 2 (Liner Interface) Edge 249.858 1977.481 37 Mid-Base 251.855 1977.761 # 2 (Liner Interface) Edge 253.852 1978.042 38 Mid-Base 255.849 1978.323 # 2 (Liner Interface) Edge 257.846 1978.604 39 Mid-Base 259.843 1978.885 # 2 (Liner Interface) Edge 261.841 1979.166 40 Mid-Base 263.838 1979.447 # 2 (Liner Interface) Edge 265.835 1979.728 41 Mid-Base 267.832 1980.008 # 2 (Liner Interface) Edge 269.829 1980.289 42 Mid-Base 271.826 1980.57 # 2 (Liner Interface)
Edge 273.823 1980.851 43 Mid-Base 275.820 1981.132 # 2 (Liner Interface) Edge 277.817 1981.413 44 Mid-Base 279.814 1981.693 # 2 (Liner Interface) Edge 281.811 1981.974 45 Mid-Base 283.808 1982.255 # 2 (Liner Interface) Edge 285.805 1982.536 46 Mid-Base 287.802 1982.817 # 2 (Liner Interface) Edge 289.799 1983.098 47 Mid-Base 291.796 1983.378 # 2 (Liner Interface) Edge 293.793 1983.659 48 Mid-Base 295.790 1983.94 # 2 (Liner Interface)
Edge 297.788 1984.221 49 Mid-Base 299.785 1984.502 # 2 (Liner Interface) Edge 301.782 1984.783 50 Mid-Base 303.779 1985.064 # 2 (Liner Interface) Edge 305.776 1985.344 51 Mid-Base 307.773 1985.625 # 2 (Liner Interface) Edge 309.770 1985.906 52 Mid-Base 311.767 1986.187 # 2 (Liner Interface) Edge 313.764 1986.468 53 Mid-Base 315.761 1986.749 # 2 (Liner Interface) Edge 317.758 1987.03 54 Mid-Base 319.755 1987.31 # 2 (Liner Interface) Edge 321.752 1987.591 55 Mid-Base 323.749 1987.872 # 2 (Liner Interface) Edge 325.746 1988.153 56 Mid-Base 327.743 1988.434 # 2 (Liner Interface) Edge 329.740 1988.715 57 Mid-Base 331.737 1988.995 # 2 (Liner Interface) Edge 333.735 1989.276 58 Mid-Base 335.732 1989.557 # 2 (Liner Interface) Edge 337.729 1989.838 59 Mid-Base 339.726 1990.119 # 2 (Liner Interface) Edge 341.723 1990.4 60 Mid-Base 343.720 1990.681 # 2 (Liner Interface) Edge 345.717 1990.961 61 Mid-Base 347.714 1991.242 # 2 (Liner Interface) Edge 349.711 1991.523 62 Mid-Base 351.708 1991.804 # 2 (Liner Interface) Edge 353.705 1992.085 63 Mid-Base 355.702 1992.366 # 2 (Liner Interface)
Edge 357.699 1992.646 64 Mid-Base 359.696 1992.927 # 2 (Liner Interface) Edge 361.693 1993.208 65 Mid-Base 363.690 1993.489 # 2 (Liner Interface) Edge 365.687 1993.77 66 Mid-Base 367.684 1994.051 # 2 (Liner Interface) Edge 369.681 1994.332 67 Mid-Base 371.679 1994.612 # 2 (Liner Interface) Edge 373.676 1994.893 68 Mid-Base 375.673 1995.174 # 2 (Liner Interface) Edge 377.670 1995.455 69 Mid-Base 379.667 1995.736 # 2 (Liner Interface)
Edge 381.664 1996.017 70 Mid-Base 383.661 1996.298 # 2 (Liner Interface) Edge 385.658 1996.578 71 Mid-Base 387.655 1996.859 # 2 (Liner Interface) Edge 389.652 1997.14 72 Mid-Base 391.649 1997.421 # 2 (Liner Interface) Edge 393.646 1997.702 73 Mid-Base 395.643 1997.983 # 2 (Liner Interface) Edge 397.640 1998.263 74 Mid-Base 399.637 1998.544 # 2 (Liner Interface) Edge 401.634 1998.825 75 Mid-Base 403.631 1999.106 # 2 (Liner Interface) Edge 405.628 1999.387 76 Mid-Base 407.626 1999.668 # 2 (Liner Interface) Edge 409.623 1999.948 77 Mid-Base 411.620 2000.229 # 2 (Liner Interface) Edge 413.617 2000.51 78 Mid-Base 415.614 2000.791 # 2 (Liner Interface) Edge 417.611 2001.072 79 Mid-Base 419.608 2001.353 # 2 (Liner Interface) Edge 421.605 2001.634 80 Mid-Base 423.602 2001.915 # 2 (Liner Interface) Edge 425.599 2002.195 81 Mid-Base 427.596 2002.476 # 2 (Liner Interface) Edge 429.593 2002.757 82 Mid-Base 431.590 2003.038 # 2 (Liner Interface) Edge 433.587 2003.319 83 Mid-Base 435.584 2003.6 # 2 (Liner Interface) Edge 437.581 2003.88 84 Mid-Base 439.578 2004.161 # 2 (Liner Interface)
Edge 441.575 2004.442 85 Mid-Base 443.573 2004.723 # 2 (Liner Interface) Edge 445.57 2005.004 86 Mid-Base 447.567 2005.285 # 2 (Liner Interface) Edge 449.564 2005.566 87 Mid-Base 451.561 2005.846 # 2 (Liner Interface) Edge 453.558 2006.127 88 Mid-Base 455.555 2006.408 # 2 (Liner Interface) Edge 457.552 2006.689 89 Mid-Base 459.549 2006.97 # 2 (Liner Interface) Edge 461.546 2007.251 90 Mid-Base 463.543 2007.531 # 2 (Liner Interface)
Edge 465.540 2007.812 91 Mid-Base 467.103 2008.529 # 2 (Liner Interface) Edge 468.666 2009.252 92 Mid-Base 470.640 2010.172 # 1 (Waste) Edge 472.614 2011.102 93 Mid-Base 474.588 2012.041 # 1 (Waste) Edge 476.563 2012.989 94 Mid-Base 478.537 2013.946 # 1 (Waste) Edge 480.511 2014.912 95 Mid-Base 482.485 2015.887 # 1 (Waste) Edge 484.459 2016.872 96 Mid-Base 486.434 2017.866 # 1 (Waste) Edge 488.408 2018.869 97 Mid-Base 490.382 2019.882 # 1 (Waste) Edge 492.356 2020.905 98 Mid-Base 494.330 2021.937 # 1 (Waste) Edge 496.304 2022.978 99 Mid-Base 498.279 2024.029 # 1 (Waste) Edge 500.253 2025.09 100 Mid-Base 502.227 2026.161 # 1 (Waste) Edge 504.201 2027.242 101 Mid-Base 506.175 2028.332 # 1 (Waste) Edge 508.15 2029.433 102 Mid-Base 510.124 2030.544 # 1 (Waste) Edge 512.098 2031.664 103 Mid-Base 514.072 2032.795 # 1 (Waste) Edge 516.046 2033.936 104
Mid-Base 518.020 2035.088 # 1 (Waste) Edge 519.995 2036.25 105 Mid-Base 521.969 2037.422 # 1 (Waste) Edge 523.943 2038.605 106 Mid-Base 525.917 2039.798 # 1 (Waste) Edge 527.891 2041.003 107 Mid-Base 529.866 2042.217 # 1 (Waste) Edge 531.840 2043.443 108 Mid-Base 533.814 2044.68 # 1 (Waste)
Edge 535.788 2045.928 109 Mid-Base 537.762 2047.187 # 1 (Waste) Edge 539.736 2048.457 110 Mid-Base 541.711 2049.738 # 1 (Waste) Edge 543.685 2051.031 111 Mid-Base 545.659 2052.334 # 1 (Waste) Edge 547.633 2053.65 112 Mid-Base 549.607 2054.977 # 1 (Waste) Edge 551.582 2056.316 113 Mid-Base 553.556 2057.667 # 1 (Waste) Edge 555.530 2059.03 114 Mid-Base 557.504 2060.405 # 1 (Waste) Edge 559.478 2061.792 115 Mid-Base 561.452 2063.191 # 1 (Waste) Edge 563.427 2064.602 116 Mid-Base 565.401 2066.026 # 1 (Waste) Edge 567.375 2067.463 117 Mid-Base 569.349 2068.912 # 1 (Waste) Edge 571.323 2070.374 118 Mid-Base 573.298 2071.849 # 1 (Waste) Edge 575.272 2073.337 119 Mid-Base 577.246 2074.838 # 1 (Waste) Edge 579.220 2076.352
120 Mid-Base 581.194 2077.88 # 1 (Waste) Edge 583.168 2079.421 121 Mid-Base 585.143 2080.977 # 1 (Waste) Edge 587.117 2082.546 122 Mid-Base 589.091 2084.129 # 1 (Waste) Edge 591.065 2085.726 123 Mid-Base 593.039 2087.337 # 1 (Waste) Edge 595.014 2088.963 124 Mid-Base 596.988 2090.603 # 1 (Waste)
Edge 598.962 2092.259 125 Mid-Base 600.936 2093.928 # 1 (Waste) Edge 602.910 2095.614 126 Mid-Base 604.884 2097.314 # 1 (Waste) Edge 606.859 2099.03 127 Mid-Base 608.833 2100.761 # 1 (Waste) Edge 610.807 2102.509 128 Mid-Base 612.781 2104.272 # 1 (Waste) Edge 614.755 2106.052 129 Mid-Base 616.73 2107.847 # 1 (Waste) Edge 618.704 2109.66 130 Mid-Base 620.678 2111.489 # 1 (Waste) Edge 622.652 2113.335 131 Mid-Base 624.626 2115.199 # 1 (Waste) Edge 626.600 2117.08 132 Mid-Base 628.575 2118.979 # 1 (Waste) Edge 630.549 2120.895 133 Mid-Base 632.523 2122.83 # 1 (Waste) Edge 634.497 2124.783 134 Mid-Base 636.471 2126.756 # 1 (Waste) Edge 638.446 2128.747 135 Mid-Base 640.420 2130.757 # 1 (Waste)
Edge 642.394 2132.787 136 Mid-Base 644.368 2134.836 # 1 (Waste) Edge 646.342 2136.906 137 Mid-Base 648.316 2138.997 # 1 (Waste) Edge 650.291 2141.108 138 Mid-Base 652.265 2143.24 # 1 (Waste) Edge 654.24 2145.394 139 Mid-Base 655.279 2146.537 # 1 (Waste) Edge 656.318 2147.685 140
Mid-Base 657.357 2148.839 # 1 (Waste) Edge 658.396 2150 Water force on right side = 0 at Y= 2150 Water force on left side = 0 at Y= 1977.5 First slice No. = 1 Last Slice No. = 140 There are no explicit external forces in the data set. Reinforcement Tallowable Tconnection Layer Position per unit per unit No. X1 Length Elevation width width Reinf. Soil X-Coord of Total Pore Force used Layer Mat'l Slip surface Vertical Pressure per unit No. No. Intersection Stress width Slice Width Vertical Pore Tan Alpha Tan Phi Weight TL(I) No. Stress Pressure 1 .5 9.15 0 .33325 .42447 4.57 -1102.21 2 .139 20.45 0 .33395 .42447 2.86 -689.33 3 3.986 140.49 0 .33331 .42447 560.02 -134807.1 4 3.986 376.31 0 .33335 .42447 1500.00 -361073.9 5 3.986 612.13 0 .33331 .42447 2439.96 -587337.8 6 3.986 847.95 0 .33331 .42447 3379.95 -813608.5 7 3.986 1083.77 0 .33334 .42447 4319.91 -1039869 8 3.985 1319.59 0 .33332 .42447 5259.88 -1266139 9 3.985 1555.39 0 .33335 .42447 6199.77 -1492379 10 3.985 1791.22 0 .33332 .42447 7139.81 -1718669 11 3.985 2027.04 0 .33335 .42447 8079.77 -1944921 12 3.986 2262.86 0 .33331 .42447 9019.82 -2171220 13 3.994 2412.89 0 -.14061 .42447 9637.38 -2289248 14 3.994 2477.14 0 -.14064 .42447 9893.99 -2350185 15 3.994 2541.39 0 -.14061 .42447 10150.61 -2411158 16 3.994 2605.66 0 -.14064 .42447 10407.31 -2472117 17 3.994 2669.92 0 -.14061 .42447 10663.97 -2533101 18 3.994 2734.17 0 -.14061 .42447 10920.59 -2594056 19 3.994 2798.43 0 -.14064 .42447 11177.24 -2655004
20 3.994 2862.69 0 -.14061 .42447 11433.9 -2715988 21 3.994 2926.94 0 -.14064 .42447 11690.56 -2776936 22 3.994 2991.19 0 -.14061 .42447 11947.17 -2837908 23 3.994 3055.45 0 -.14064 .42447 12203.83 -2898857 24 3.994 3119.71 0 -.14061 .42447 12460.49 -2959840 25 3.994 3183.97 0 -.14061 .42447 12717.15 -3020805 26 3.994 3248.23 0 -.14064 .42447 12973.8 -3081756 27 3.994 3312.49 0 -.14061 .42447 13230.46 -3142737 28 3.994 3376.74 0 -.14064 .42447 13487.07 -3203677 29 3.994 3440.98 0 -.14061 .42447 13743.69 -3264647 30 3.994 3505.25 0 -.14061 .42447 14000.39 -3325624 31 3.994 3569.51 0 -.14064 .42447 14257.05 -3386576 32 3.994 3633.76 0 -.14061 .42447 14513.66 -3447544 33 3.994 3698.02 0 -.14064 .42447 14770.32 -3508497 34 3.994 3762.28 0 -.14061 .42447 15026.98 -3569475 35 3.994 3826.54 0 -.14064 .42447 15283.63 -3630429 36 3.994 3890.79 0 -.14061 .42447 15540.25 -3691395 37 3.994 3955.06 0 -.14061 .42447 15796.95 -3752372
38 3.994 4019.30 0 -.14064 .42447 16053.56 -3813318 39 3.994 4083.55 0 -.14061 .42447 16310.18 -3874282 40 3.994 4147.81 0 -.14064 .42447 16566.84 -3935240 41 3.994 4212.08 0 -.14061 .42447 16823.54 -3996223 42 3.994 4276.33 0 -.14061 .42447 17080.15 -4057178 43 3.994 4340.59 0 -.14064 .42447 17336.81 -4118139 44 3.994 4404.85 0 -.14061 .42447 17593.47 -4179110 45 3.994 4469.11 0 -.14064 .42447 17850.12 -4240071 46 3.994 4533.35 0 -.14061 .42447 18106.74 -4301029 47 3.994 4597.62 0 -.14061 .42447 18363.44 -4362007 48 3.994 4661.87 0 -.14064 .42447 18620.05 -4422960 49 3.994 4726.12 0 -.14061 .42447 18876.67 -4483916 50 3.994 4790.39 0 -.14064 .42447 19133.37 -4544893 51 3.994 4854.65 0 -.14061 .42447 19390.02 -4605857 52 3.994 4918.90 0 -.14064 .42447 19646.64 -4666815 53 3.994 4983.15 0 -.14061 .42447 19903.25 -4727766 54 3.994 5047.43 0 -.14061 .42447 20160 -4788754 55 3.994 5111.68 0 -.14064 .42447 20416.61 -4849715 56 3.994 5175.92 0 -.14061 .42447 20673.22 -4910663 57 3.994 5240.18 0 -.14064 .42447 20929.88 -4971637 58 3.994 5304.44 0 -.14061 .42447 21186.54 -5032594 59 3.994 5368.69 0 -.14061 .42447 21443.15 -5093548 60 3.994 5432.97 0 -.14064 .42447 21699.9 -5154546 61 3.994 5497.21 0 -.14061 .42447 21956.47 -5215480 62 3.994 5561.48 0 -.14064 .42447 22213.17 -5276469 63 3.994 5625.70 0 -.14061 .42447 22469.7 -5337388 64 3.994 5690 0 -.14061 .42447 22726.49 -5398386 65 3.994 5754.22 0 -.14064 .42447 22983.01 -5459337 66 3.994 5818.49 0 -.14061 .42447 23239.71 -5520295 67 3.994 5882.77 0 -.14064 .42447 23496.46 -5581302 68 3.994 5947.01 0 -.14061 .42447 23753.03 -5642226 69 3.994 6011.28 0 -.14064 .42447 24009.73 -5703225 70 3.994 6075.51 0 -.14061 .42447 24266.26 -5764133 71 3.994 6139.80 0 -.14061 .42447 24523.05 -5825132 72 3.994 6204.02 0 -.14064 .42447 24779.57 -5886094 73 3.994 6268.29 0 -.14061 .42447 25036.27 -5947040 74 3.994 6332.53 0 -.14064 .42447 25292.84 -6008016 75 3.994 6396.81 0 -.14061 .42447 25549.59 -6068972 76 3.994 6461.06 0 -.14061 .42447 25806.2 -6129925 77 3.994 6525.32 0 -.14064 .42447 26062.86 -6190927 78 3.994 6589.60 0 -.14061 .42447 26319.61 -6251877 79 3.994 6653.83 0 -.14064 .42447 26576.13 -6312851 80 3.994 6718.10 0 -.14061 .42447 26832.83 -6373785 81 3.994 6782.33 0 -.14064 .42447 27089.4 -6434774 82 3.994 6846.61 0 -.14061 .42447 27346.15 -6495716 83 3.994 6910.84 0 -.14061 .42447 27602.67 -6556649 84 3.994 6975.12 0 -.14064 .42447 27859.42 -6617685 85 3.994 7039.36 0 -.14061 .42447 28115.99 -6678580 86 3.994 7103.63 0 -.14064 .42447 28372.69 -6739608 87 3.994 7167.90 0 -.14061 .42447 28629.39 -6800529 88 3.994 7232.15 0 -.14061 .42447 28886.01 -6861486 89 3.994 7296.42 0 -.14064 .42447 29142.71 -6922521 90 3.993 7360.64 0 -.14062 .42447 29397.44 -6982985 91 3.125 7363.26 0 -.46052 .42447 23017.38 -5703894 92 3.948 7306.95 0 -.46863 .52056 28850.51 -8767863 93 3.948 7252.29 0 -.47781 .52056 28634.7 -8702278 94 3.948 7194.37 0 -.48706 .52056 28406.01 -8632778 95 3.948 7133.10 0 -.49642 .52056 28164.1 -8559257 96 3.948 7068.53 0 -.50588 .52056 27909.16 -8481781 97 3.948 7000.55 0 -.51547 .52056 27640.74 -8400205 98 3.948 6929.15 0 -.52515 .52056 27358.82 -8314530 99 3.948 6854.31 0 -.53498 .52056 27063.33 -8224729 100 3.948 6775.92 0 -.54487 .52056 26753.83 -8130669
101 3.948 6694.02 0 -.55495 .52056 26430.45 -8032390 102 3.948 6608.52 0 -.56512 .52056 26092.88 -7929801 103 3.948 6519.35 0 -.57542 .52056 25740.78 -7822796 104 3.948 6426.52 0 -.58590 .52056 25374.28 -7711413 105 3.948 6329.93 0 -.59650 .52056 24992.9 -7595510 106 3.948 6229.55 0 -.60726 .52056 24596.55 -7475058 107 3.948 6125.35 0 -.61814 .52056 24185.12 -7350019 108 3.948 6017.19 0 -.62924 .52056 23758.06 -7220233 109 3.948 5905.10 0 -.64046 .52056 23315.52 -7085741 110 3.948 5789.00 0 -.65190 .52056 22857.1 -6946425 111 3.948 5668.77 0 -.66347 .52056 22382.37 -6802151 112 3.948 5544.42 0 -.67528 .52056 21891.41 -6652948 113 3.948 5415.84 0 -.68721 .52056 21383.72 -6498655 114 3.948 5282.95 0 -.69945 .52056 20859.02 -6339195 115 3.948 5145.71 0 -.71182 .52056 20317.14 -6174515 116 3.948 5004.00 0 -.72450 .52056 19757.65 -6004482 117 3.948 4857.78 0 -.73730 .52056 19180.29 -5829018 118 3.948 4706.98 0 -.75040 .52056 18584.88 -5648070 119 3.948 4551.43 0 -.76376 .52056 17970.73 -5461427 120 3.948 4391.12 0 -.77730 .52056 17337.76 -5269062 121 3.948 4225.95 0 -.79128 .52056 16685.62 -5070871 122 3.948 4055.73 0 -.80537 .52056 16013.52 -4866616 123 3.948 3880.48 0 -.81991 .52056 15321.55 -4656323 124 3.948 3700.02 0 -.83468 .52056 14609.02 -4439781 125 3.948 3514.24 0 -.84977 .52056 13875.5 -4216858 126 3.948 3323.03 0 -.86523 .52056 13120.55 -3987423 127 3.948 3126.24 0 -.88106 .52056 12343.56 -3751292 128 3.948 2923.81 0 -.89726 .52056 11544.28 -3508384 129 3.948 2715.53 0 -.91389 .52056 10721.92 -3258463 130 3.948 2501.25 0 -.93090 .52056 9875.87 -3001345 131 3.948 2280.87 0 -.94833 .52056 9005.71 -2736896 132 3.948 2054.18 0 -.96633 .52056 8110.64 -2464881 133 3.948 1821.02 0 -.98475 .52056 7190.08 -2185114 134 3.948 1581.26 0 -1.00374 .52056 6243.39 -1897411 135 3.948 1334.59 0 -1.02328 .52056 5269.47 -1601429 136 3.948 1080.96 0 -1.04337 .52056 4268.05 -1297089 137 3.948 820.04 0 -1.06409 .52056 3237.82 -983995.9 138 3.948 551.62 0 -1.08545 .52056 2178.31 -662004.1 139 2.078 311.70 0 -1.10227 .52056 647.72 -196847.1 140 2.078 104.45 0 -1.11414 .52056 217.06 -65967.22 SLICE MALPHA DELTANUM N.FORCE N.LEVER RADIUS DEL.PF Cohesion 1 .86602 -1272.7 5.2 -73.93 -567.09 -390.90 0 2 .86567 -796.2 3.3 -74.62 -567.04 -246.89 0 3 .86599 -155667.2 646.6 -76.48 -567.09 -49459.09 0 4 .86597 -416954.2 1732.1 -80.69 -567.08 -139781.4 0 5 .86599 -678222.9 2817.5 -84.88 -567.09 -239163.4 0 6 .86599 -939506.9 3902.9 -89.08 -567.09 -347699.3 0 7 .86598 -1200800 4988.4 -93.30 -567.08 -465438.1 0 8 .86599 -1462063 6073.8 -97.48 -567.09 -592132 0 9 .86597 -1723342 7159.2 -101.70 -567.08 -728144.9 0 10 .86599 -1984618 8244.6 -105.89 -567.09 -873046.9 0 11 .86597 -2245921 9330.2 -110.10 -567.08 -1027349 0 12 .86599 -2507194 10415.5 -114.29 -567.09 -1190441 0 13 1.02667 -2229777 9387.0 146.25 -559.60 1372870 0 14 1.02667 -2289123 9636.9 142.23 -559.60 1370712 0 15 1.02667 -2348520 9886.9 138.18 -559.60 1366224 0 16 1.02667 -2407886 10136.9 134.16 -559.60 1360054 0 17 1.02667 -2467294 10386.9 130.11 -559.60 1351530 0 18 1.02667 -2526666 10636.8 126.08 -559.60 1341150 0 19 1.02667 -2586022 10886.8 122.06 -559.60 1328937 0 20 1.02667 -2645430 11136.8 118.01 -559.60 1314351 0
21 1.02667 -2704786 11386.8 114.00 -559.60 1298113 0 22 1.02667 -2764183 11636.8 109.95 -559.60 1279480 0 23 1.02667 -2823539 11886.7 105.93 -559.60 1259218 0 24 1.02667 -2882947 12136.7 101.88 -559.60 1236549 0 25 1.02667 -2942329 12386.7 97.85 -559.60 1212058 0 26 1.02667 -3001685 12636.7 93.83 -559.60 1185758 0 27 1.02667 -3061093 12886.7 89.78 -559.60 1157026 0 28 1.02667 -3120439 13136.6 85.76 -559.60 1126699 0 29 1.02667 -3179836 13386.6 81.71 -559.60 1093921 0 30 1.02667 -3239228 13636.6 77.68 -559.60 1059351 0 31 1.02667 -3298586 13886.6 73.66 -559.60 1022990 0 32 1.02667 -3357981 14136.6 69.61 -559.60 984149.8 0 33 1.02667 -3417339 14386.5 65.60 -559.60 943764.8 0 34 1.02667 -3476745 14636.6 61.55 -559.60 900886.4 0 35 1.02667 -3536103 14886.5 57.53 -559.60 856476.6 0 36 1.02667 -3595498 15136.5 53.48 -559.60 809553.6 0 37 1.02667 -3654891 15386.5 49.45 -559.60 760866.4 0 38 1.02667 -3714240 15636.4 45.43 -559.60 710417.7 0 39 1.02667 -3773633 15886.4 41.38 -559.60 657432.4 0 40 1.02667 -3832994 16136.4 37.36 -559.60 602962.4 0 41 1.02667 -3892407 16386.4 33.31 -559.60 545938.3 0 42 1.02667 -3951778 16636.4 29.28 -559.60 487164.2 0 43 1.02667 -4011141 16886.3 25.26 -559.60 426656.6 0 44 1.02667 -4070543 17136.4 21.21 -559.60 363568.9 0 45 1.02667 -4129905 17386.3 17.19 -559.60 299036.3 0 46 1.02667 -4189294 17636.3 13.14 -559.60 231906 0 47 1.02667 -4248688 17886.3 9.11 -559.60 163050.2 0 48 1.02667 -4308043 18136.2 5.09 -559.60 92482.09 0 49 1.02667 -4367430 18386.2 1.04 -559.60 19288.02 0 50 1.02667 -4426807 18636.2 -2.96 -559.60 -55303.52 0 51 1.02667 -4486203 18886.3 -7.01 -559.60 -132539.6 0 52 1.02667 -4545561 19136.1 -11.03 -559.60 -211155.7 0 53 1.02667 -4604945 19386.1 -15.08 -559.60 -292433.1 0 54 1.02667 -4664348 19636.2 -19.11 -559.60 -375405.3 0 55 1.02667 -4723709 19886.1 -23.13 -559.60 -460058.8 0 56 1.02667 -4783090 20136.1 -27.18 -559.60 -547397.4 0 57 1.02667 -4842464 20386.0 -31.20 -559.60 -636075.4 0 58 1.02667 -4901854 20636.1 -35.25 -559.60 -727457.2 0 59 1.02667 -4961225 20886.0 -39.28 -559.60 -820511.6 0 60 1.02667 -5020620 21136.0 -43.30 -559.60 -915227.5 0 61 1.02667 -5079989 21386.0 -47.35 -559.60 -1012671 0 62 1.02667 -5139375 21636.0 -51.36 -559.60 -1111409 0 63 1.02667 -5198730 21885.9 -55.41 -559.60 -1212892 0 64 1.02667 -5258144 22136.0 -59.45 -559.60 -1316036 0 65 1.02667 -5317493 22385.8 -63.46 -559.60 -1420803 0 66 1.02667 -5376885 22635.9 -67.51 -559.60 -1528357 0 67 1.02667 -5436289 22885.9 -71.53 -559.60 -1637161 0 68 1.02667 -5495648 23135.9 -75.58 -559.60 -1748749 0 69 1.02667 -5555043 23385.9 -79.60 -559.60 -1861574 0 70 1.02667 -5614389 23635.8 -83.65 -559.60 -1977201 0 71 1.02667 -5673803 23885.9 -87.68 -559.60 -2094465 0 72 1.02667 -5733161 24135.7 -91.70 -559.60 -2213311 0 73 1.02667 -5792544 24385.8 -95.75 -559.60 -2335016 0 74 1.02667 -5851916 24635.6 -99.76 -559.60 -2457888 0 75 1.02667 -5911308 24885.8 -103.81 -559.60 -2583640 0 76 1.02667 -5970678 25135.7 -107.85 -559.60 -2710972 0 77 1.02667 -6030074 25385.6 -111.86 -559.60 -2839889 0 78 1.02667 -6089462 25635.8 -115.91 -559.60 -2971705 0 79 1.02667 -6148830 25885.6 -119.93 -559.60 -3104633 0 80 1.02667 -6208203 26135.7 -123.98 -559.60 -3240486 0 81 1.02667 -6267585 26385.5 -128.00 -559.60 -3377441 0 82 1.02667 -6326966 26635.7 -132.05 -559.60 -3517343 0 83 1.02667 -6386316 26885.6 -136.08 -559.60 -3658779 0
84 1.02667 -6445744 27135.5 -140.10 -559.60 -3801791 0 85 1.02667 -6505080 27385.5 -144.15 -559.60 -3947734 0 86 1.02667 -6564500 27635.5 -148.17 -559.60 -4094765 0 87 1.02667 -6623861 27885.6 -152.22 -559.60 -4244770 0 88 1.02667 -6683234 28135.5 -156.25 -559.60 -4396298 0 89 1.02667 -6742660 28385.5 -160.27 -559.60 -4549366 0 90 1.02667 -6801570 28633.7 -164.31 -559.60 -4704975 0 91 1.01769 -5604707 22617.1 0 -583.79 0 0 92 1.04158 -8417778 27698.5 0 -583.79 0 0 93 1.04055 -8363115 27518.6 0 -583.79 0 0 94 1.03946 -8305043 27327.6 0 -583.79 0 0 95 1.03830 -8243495 27125.0 0 -583.79 0 0 96 1.03708 -8178486 26911.1 0 -583.79 0 0 97 1.03579 -8109883 26685.4 0 -583.79 0 0 98 1.03445 -8037632 26447.7 0 -583.79 0 0 99 1.03303 -7961748 26198 0 -583.79 0 0 100 1.03155 -7881970 25935.4 0 -583.79 0 0 101 1.02999 -7798447 25660.6 0 -583.79 0 0 102 1.02838 -7710950 25372.7 0 -583.79 0 0 103 1.02669 -7619376 25071.4 0 -583.79 0 0 104 1.02493 -7523802 24756.9 0 -583.79 0 0 105 1.02310 -7423971 24428.4 0 -583.79 0 0 106 1.02120 -7319852 24085.8 0 -583.79 0 0 107 1.01923 -7211319 23728.7 0 -583.79 0 0 108 1.01717 -7098290 23356.8 0 -583.79 0 0 109 1.01505 -6980628 22969.6 0 -583.79 0 0 110 1.01285 -6858283 22567.0 0 -583.79 0 0 111 1.01057 -6730941 22148.0 0 -583.79 0 0 112 1.00821 -6598730 21713.0 0 -583.79 0 0 113 1.00578 -6461259 21260.6 0 -583.79 0 0 114 1.00325 -6318623 20791.3 0 -583.79 0 0 115 1.00065 -6170446 20303.7 0 -583.79 0 0 116 .99795 -6016758 19798.0 0 -583.79 0 0 117 .99519 -5857151 19272.8 0 -583.79 0 0 118 .99233 -5691715 18728.4 0 -583.79 0 0 119 .98937 -5520060 18163.6 0 -583.79 0 0 120 .98635 -5341977 17577.6 0 -583.79 0 0 121 .98319 -5157546 16970.8 0 -583.79 0 0 122 .97998 -4966032 16340.6 0 -583.79 0 0 123 .97663 -4767698 15688.0 0 -583.79 0 0 124 .97321 -4561971 15011.0 0 -583.79 0 0 125 .96969 -4348645 14309.1 0 -583.79 0 0 126 .96606 -4127491 13581.4 0 -583.79 0 0 127 .96232 -3898146 12826.7 0 -583.79 0 0 128 .95848 -3660348 12044.3 0 -583.79 0 0 129 .95452 -3413712 11232.7 0 -583.79 0 0 130 .95045 -3157785 10390.6 0 -583.79 0 0 131 .94628 -2892263 9516.9 0 -583.79 0 0 132 .94196 -2616745 8610.3 0 -583.79 0 0 133 .93753 -2330691 7669.1 0 -583.79 0 0 134 .93297 -2033711 6691.8 0 -583.79 0 0 135 .92828 -1725139 5676.5 0 -583.79 0 0 136 .92347 -1404576 4621.7 0 -583.79 0 0 137 .91852 -1071283 3525.0 0 -583.79 0 0 138 .91342 -724746.5 2384.7 0 -583.79 0 0 139 .90943 -216449.9 712.2 0 -583.79 0 0 140 .90662 -72761.3 239.4 0 -583.79 0 0 ---------------------------------------------------------------------------- NUM = -6.36059E+08 PF = -5.890639E+07 PF is Total Moment due to Normal forces SWX = -4.52466E+08 FACTOR OF SAFETY = 1.616169
Bishop Factor of Safety = NUM! /(SWX + EQM + GridMoment - PF!) Weight Moment = -4.52466E+08 Water Moments = 0 Ext.Force Moment = 0 ----------- SWX = -4.52466E+08 0 is the moment due to the horizontal components of the active external forces, along with a minor adjustment for non-coincidence of the force locations with the centrelines of the slices they act on. The vertical components are treated as part of the slice weight. Geogrid Moment = 0 Earthquake Moment EQM = 0 NUM is Total of (TL(ie Top Line)/MALPHA) for all slices) Malpha values shown are for final iteration. TL for any slice is given by :- Radius ( Width ( Cohesion + Tan Fy (Vertical Stress - Pore pressure))) No. of slices used in analysis = 140 NUMJ= 1211824 WTANALPHA= -787758.7 WEIGHT= 2471621 FLAGRI=-1 HFORCE= 0 SEISMIC= 0 HForceGrids = 0 (NUMJ*FLAGRI) Unfactored Janbu FoS = --------------------- WTANALPHA+WEIGHT*SEISMIC*FLAGRI+WFL-WFR-HFORCE-HForcegrids*FLAGRI Unf. Janbu FoS = 1.538318
Seismic Analysis.xlsx in
C:\Users\cmoeller\Documents\Buncombe LF Expansion\Stability\5/15/2017
Cross-Section ky/g(1)kmax/g(2)ky/kmax
U6.5/g(3)
(cm)
U6.5/g(3)
(inch)
U6.5/g(3)
(inch) <4 inches?
A-A Left 0.17 0.226 0.752 2.1 0.83 yes. OK
A-A Right 0.185 0.226 0.819 1.2 0.47 yes. OK
B-B Left 0.167 0.226 0.739 1.8 0.71 yes. OK
Notes:
2- kmax = peak ground acceleration from USGS
Reference:
1- ky = yield acceleration (Factor of Safety = 1)
3- U6.5 = displacement based on an earthquake magnitude of 6.5 from Makdisi and Seed (1978) - See
Chart Below
4 - For seismic slope stability analysis the MSW strength properties = cohesion 0 psf; friction angle 27.5
degrees
F. Makdisi, and H. Seed, "Simplified Procedure for Estimating Dam and Embankment Earthquake-Induced Deformation,"
Journal of the Geotechnical Engineering Division, Vol. 104, No. GT7, pp. 849-867, 1978.
Buncombe Slope Stability - Seismic Analyses Summary
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HHNT - Macon, GA 1401-010 Buncombe County LF Expansion 5/12/2017 Section A-A - Left Seismic - Find ky
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LIMIT EQUILIBRIUM SLOPE STABILITY ANALYSIS GSLOPE analysis run by:- HHNT - Macon, GA 9Q6340W Results are for Janbu's Simplified Method unless otherwise noted. File C:\Users\cmoeller\Documents\Buncombe LF Expansion\Stability\A-A Left Seismic.gsl Output dated 05-15-2017 at 14:41:29 Material Unit Wt Cohesion Friction Min. Piezo Ru Interaction Angle c/p Surf. Coefficient 1 Waste 90 0 27.5 0 0 0 0 2 Liner Interface 110 0 23 0 0 0 0 3 Slide Surface -1 0 0 0 0 0 0 X-centre Y-centre Radius Factor Iterations Slices M Alpha of Safety Warnings -95 3170 1275 1.0058 4 18 0 ------------------------------------------------------------------------------- DETAILED SLICE PRINTOUT Intersection points of Slip Surface with Material Surfaces:- X Y -434.387 1941 670 2150 -434.387 1941 469.079 2026.567 -434.387 1941 466.483 2025.29 Slice No X-Coord Y-Coord MATERIAL Edge 255 2017.5 1 Mid-Base 255.29 2017.41 # 2 (Liner Interface) Edge 255.58 2017.319 2 Mid-Base 264.26 2014.615 # 2 (Liner Interface) Edge 272.94 2011.91 3 Mid-Base 281.62 2009.205 # 2 (Liner Interface) Edge 290.3 2006.5
4 Mid-Base 304.982 2008.066 # 2 (Liner Interface) Edge 319.663 2009.632 5 Mid-Base 334.345 2011.198 # 2 (Liner Interface) Edge 349.027 2012.763 6 Mid-Base 363.709 2014.329 # 2 (Liner Interface)
Edge 378.391 2015.895 7 Mid-Base 393.073 2017.461 # 2 (Liner Interface) Edge 407.755 2019.027 8 Mid-Base 422.437 2020.593 # 2 (Liner Interface) Edge 437.119 2022.158 9 Mid-Base 451.801 2023.724 # 2 (Liner Interface) Edge 466.483 2025.29 10 Mid-Base 467.781 2025.927 # 2 (Liner Interface) Edge 469.079 2026.567 11 Mid-Base 484.159 2034.131 # 1 (Waste) Edge 499.239 2041.947 12 Mid-Base 514.319 2050.02 # 1 (Waste) Edge 529.4 2058.357 13 Mid-Base 543.04 2066.13 # 1 (Waste) Edge 556.68 2074.127 14 Mid-Base 570.319 2082.354 # 1 (Waste) Edge 583.96 2090.816 15 Mid-Base 597.6 2099.519 # 1 (Waste) Edge 611.239 2108.468 16 Mid-Base 624.879 2117.67 # 1 (Waste) Edge 638.519 2127.132 17 Mid-Base 652.159 2136.861 # 1 (Waste) Edge 665.8 2146.864 18 Mid-Base 667.9 2148.428 # 1 (Waste) Edge 670 2150 Water force on right side = 0 at Y= 2150 Water force on left side = 0 at Y= 2017.5 First slice No. = 1 Last Slice No. = 18 There are no explicit external forces in the data set.
Reinforcement Tallowable Tconnection Layer Position per unit per unit No. X1 Length Elevation width width Reinf. Soil X-Coord of Total Pore Force used Layer Mat'l Slip surface Vertical Pressure per unit No. No. Intersection Stress width Slice Width Vertical Pore Tan Alpha Tan Phi Weight TL(I) No. Stress Pressure 1 .580 9.93 0 .31169 .42447 5.76 -2436.88 2 17.36 519.72 0 .31160 .42447 9022.47 -3815228 3 17.359 1519.44 0 .31161 .42447 26377.6 -11153930
4 29.363 2305.17 0 -.10665 .42447 67689.14 -34415590 5 29.363 2876.92 0 -.10664 .42447 84478 -42951600 6 29.363 3448.70 0 -.10665 .42447 101267.5 -51488040 7 29.363 4020.44 0 -.10664 .42447 118056 -60023860 8 29.363 4592.18 0 -.10665 .42447 134844.6 -68559820 9 29.363 5163.95 0 -.10664 .42447 151633.8 -77095950 10 2.595 5420.19 0 -.49191 .42447 14069.21 -7614330 11 30.160 5147.99 0 -.50994 .52056 155265.3 -103053100 12 30.160 4594.68 0 -.54410 .52056 138577.1 -91976820 13 27.279 3979.73 0 -.57806 .52056 108566.9 -72058380 14 27.279 3312.57 0 -.61177 .52056 90366.96 -59978630 15 27.279 2560.78 0 -.64707 .52056 69858.03 -46366380 16 27.279 1720.15 0 -.68416 .52056 46925.68 -31145650 17 27.280 786.02 0 -.72329 .52056 21442.91 -14232150 18 4.200 141.43 0 -.74677 .52056 594.04 -394278.8 SLICE MALPHA DELTANUM N.FORCE N.LEVER RADIUS DEL.PF Cohesion 1 .82911 -2939.1 6.9 -677.40 -996.13 -4708.68 0 2 .82917 -4601256 10881.3 -686.72 -996.19 -7472432 0 3 .82916 -13451990 31812.1 -704.91 -996.18 -22424770 0 4 1.03911 -33120070 65141.0 -274.50 -1197.8 -17881430 0 5 1.03911 -41334810 81298.0 -304.03 -1197.79 -24717730 0 6 1.03911 -49549850 97455.4 -333.56 -1197.8 -32507620 0 7 1.03911 -57764420 113612.1 -363.09 -1197.79 -41252500 0 8 1.03911 -65979000 129768.5 -392.62 -1197.8 -50950360 0 9 1.03911 -74193890 145925.9 -422.16 -1197.79 -61604080 0 10 1.08358 -7026952 12983.8 0 -1275 0 0 11 1.12597 -91523590 137894.3 0 -1275 0 0 12 1.12575 -81702540 123097.3 0 -1275 0 0 13 1.12477 -64064740 96523.3 0 -1275 0 0 14 1.12312 -53403500 80460.5 0 -1275 0 0 15 1.12073 -41371550 62332.5 0 -1275 0 0 16 1.11756 -27869190 41989.1 0 -1275 0 0 17 1.11358 -12780480 19255.7 0 -1275 0 0 18 1.11091 -354913.8 534.7 0 -1275 0 0 ---------------------------------------------------------------------------- NUM = -7.200956E+08 PF = -2.588156E+08 PF is Total Moment due to Normal forces SWX = -7.435933E+08 FACTOR OF SAFETY = 0.9770935 Bishop Factor of Safety = NUM! /(SWX + EQM + GridMoment - PF!)
Weight Moment = -7.435933E+08 Water Moments = 0 Ext.Force Moment = 0 ----------- SWX = -7.435933E+08 0 is the moment due to the horizontal components of the active external forces, along with a minor adjustment for non-coincidence of the force locations with the centrelines of the slices they act on. The vertical components are treated as part of the slice weight. Geogrid Moment = 0 Earthquake Moment EQM =-2.521996E+08 NUM is Total of (TL(ie Top Line)/MALPHA) for all slices) Malpha values shown are for final iteration.
TL for any slice is given by :- Radius ( Width ( Cohesion + Tan Fy (Vertical Stress - Pore pressure))) No. of slices used in analysis = 18 NUMJ= 629301.8 WTANALPHA= -431940.6 WEIGHT= 1339041 FLAGRI=-1 HFORCE= 0 SEISMIC= 0.17 HForceGrids = 0 (NUMJ*FLAGRI) Unfactored Janbu FoS = --------------------- WTANALPHA+WEIGHT*SEISMIC*FLAGRI+WFL-WFR-HFORCE-HForcegrids*FLAGRI Unf. Janbu FoS = 0.9540983
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HHNT - Macon, GA 1401-010 Buncombe County LF Expansion 5/12/2017 Section A-A - Right Seismic - Find ky
0
20
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40
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1200F = 1.
LIMIT EQUILIBRIUM SLOPE STABILITY ANALYSIS GSLOPE analysis run by:- HHNT - Macon, GA 9Q6340W Results are for Janbu's Simplified Method unless otherwise noted. File C:\Users\cmoeller\Documents\Buncombe LF Expansion\Stability\A-A Right Seismic ky.gsl Output dated 05-15-2017 at 14:46:40 Material Unit Wt Cohesion Friction Min. Piezo Ru Interaction Angle c/p Surf. Coefficient 1 Waste 90 0 27.5 0 0 0 0 2 Liner Interface 110 0 23 0 0 0 0 3 Slide Surface -1 0 0 0 0 0 0 X-centre Y-centre Radius Factor Iterations Slices M Alpha of Safety Warnings 1280 2750 800 1.0006 4 16 0 ------------------------------------------------------------------------------- DETAILED SLICE PRINTOUT Intersection points of Slip Surface with Material Surfaces:- X Y 760.560 2141.573 1566.341 2003 1016.534 1994.629 1566.341 2003 1019.457 1993.616 1566.341 2003 Slice No X-Coord Y-Coord MATERIAL Edge 760.560 2141.573 1 Mid-Base 776.559 2128.271 # 1 (Waste) Edge 792.557 2115.65 2 Mid-Base 808.555 2103.672 # 1 (Waste) Edge 824.553 2092.3 3 Mid-Base 840.552 2081.505 # 1 (Waste) Edge 856.550 2071.258
4 Mid-Base 872.548 2061.535 # 1 (Waste) Edge 888.547 2052.315 5 Mid-Base 904.545 2043.577 # 1 (Waste) Edge 920.543 2035.303 6 Mid-Base 936.541 2027.479 # 1 (Waste)
Edge 952.540 2020.089 7 Mid-Base 968.538 2013.12 # 1 (Waste) Edge 984.536 2006.561 8 Mid-Base 1000.535 2000.401 # 1 (Waste) Edge 1016.534 1994.629 9 Mid-Base 1017.995 1994.121 # 2 (Liner Interface) Edge 1019.457 1993.615 10 Mid-Base 1032.886 1993.554 # 2 (Liner Interface) Edge 1046.316 1993.492 11 Mid-Base 1059.745 1993.431 # 2 (Liner Interface) Edge 1073.174 1993.369 12 Mid-Base 1086.604 1993.308 # 2 (Liner Interface) Edge 1100.033 1993.246 13 Mid-Base 1113.462 1993.185 # 2 (Liner Interface) Edge 1126.891 1993.123 14 Mid-Base 1140.321 1993.062 # 2 (Liner Interface) Edge 1153.75 1993 15 Mid-Base 1168.125 1998.16 # 2 (Liner Interface) Edge 1182.5 2003.321 16 Mid-Base 1182.75 2003.41 # 2 (Liner Interface) Edge 1183 2003.5 Water force on right side = 0 at Y= 2003.5 Water force on left side = 0 at Y= 2141.573 First slice No. = 1 Last Slice No. = 16 There are no explicit external forces in the data set. Reinforcement Tallowable Tconnection Layer Position per unit per unit No. X1 Length Elevation width width Reinf. Soil X-Coord of Total Pore Force used
Layer Mat'l Slip surface Vertical Pressure per unit No. No. Intersection Stress width Slice Width Vertical Pore Tan Alpha Tan Phi Weight TL(I) No. Stress Pressure 1 31.996 726.08 0 .81019 .52056 23232.28 9675169 2 31.996 1997.62 0 .72976 .52056 63917.08 26618500 3 31.996 3050.33 0 .65764 .52056 97600.2 40645960 4 31.996 3905.24 0 .59203 .52056 124954.5 52037740 5 31.996 4579.17 0 .53166 .52056 146518.1 61017980 6 31.996 5085.65 0 .47550 .52056 162723.7 67766880 7 31.996 5435.58 0 .42279 .52056 173920.1 72429680 8 31.996 5638.04 0 .37291 .52056 180399.1 75127860 9 2.923 5699.01 0 .34663 .42447 16661.9 5658046
10 26.858 5321.43 0 .00458 .42447 142926.1 45960660 11 26.858 4541.48 0 .00458 .42447 121977.7 39224350 12 26.858 3761.57 0 .00458 .42447 101030.2 32488230 13 26.858 2981.63 0 .00458 .42447 80082.42 25752100 14 26.858 2201.68 0 .00458 .42447 59134.32 19015800 15 28.75 915.72 0 -.35897 .42447 26327.17 7485481 16 .5 9.86 0 -.35888 .42447 4.93 1403.11 SLICE MALPHA DELTANUM N.FORCE N.LEVER RADIUS DEL.PF Cohesion 1 1.10446 8760026 21034.8 0 800 0 0 2 1.11443 23885220 57353.8 0 800 0 0 3 1.12135 36247270 87037.9 0 800 0 0 4 1.12552 46234390 111019.3 0 800 0 0 5 1.12717 54133750 129987.5 0 800 0 0 6 1.12649 60157390 144451.6 0 800 0 0 7 1.12364 64459890 154782.9 0 800 0 0 8 1.11873 67154230 161252.6 0 800 0 0 9 1.08377 5220698 15373.9 0 800 0 0 10 1.00193 45872000 142650.4 243.64 757.57 34756120 0 11 1.00193 39148610 121742.1 216.78 757.57 26391630 0 12 1.00193 32425560 100835.3 189.92 757.57 19151440 0 13 1.00193 25702370 79927.7 163.06 757.57 13033460 0 14 1.00193 18979120 59020.2 136.21 757.57 8039159 0 15 .79787 9381742 32996.5 359.31 669.82 11856210 0 16 .79793 1758.4 6.1 343.72 669.85 2125.70 0 ---------------------------------------------------------------------------- NUM = 5.37764E+08 PF = 1.132302E+08 PF is Total Moment due to Normal forces SWX = 4.617487E+08 FACTOR OF SAFETY = 0.9841736 Bishop Factor of Safety = NUM! /(SWX + EQM + GridMoment - PF!) Weight Moment = 4.617487E+08 Water Moments = 0 Ext.Force Moment = 0 ----------- SWX = 4.617487E+08 0 is the moment due to the horizontal components of the active external forces, along with a minor adjustment for non-coincidence of the force locations with the centrelines of the slices they act on.
The vertical components are treated as part of the slice weight. Geogrid Moment = 0 Earthquake Moment EQM = 1.978931E+08 NUM is Total of (TL(ie Top Line)/MALPHA) for all slices) Malpha values shown are for final iteration. TL for any slice is given by :- Radius ( Width ( Cohesion + Tan Fy (Vertical Stress - Pore pressure))) No. of slices used in analysis = 16 NUMJ= 739520.1 WTANALPHA= 498348.6 WEIGHT= 1521410 FLAGRI= 1 HFORCE= 0 SEISMIC= 0.185 HForceGrids = 0
(NUMJ*FLAGRI) Unfactored Janbu FoS = --------------------- WTANALPHA+WEIGHT*SEISMIC*FLAGRI+WFL-WFR-HFORCE-HForcegrids*FLAGRI Unf. Janbu FoS = 0.9483345
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HHNT - Macon, GA 1401-010 Buncombe County LF Expansion 5/12/2017 Section B-B - Left Seismic - Find ky
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15
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35
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LIMIT EQUILIBRIUM SLOPE STABILITY ANALYSIS GSLOPE analysis run by:- HHNT - Macon, GA 9Q6340W Results are for Janbu's Simplified Method unless otherwise noted. File C:\Users\cmoeller\Documents\Buncombe LF Expansion\Stability\B-B Left Seismic Find Ky.gsl Output dated 05-15-2017 at 14:35:18 Material Unit Wt Cohesion Friction Min. Piezo Ru Interaction Angle c/p Surf. Coefficient 1 Waste 90 0 27.5 0 0 0 0 2 Liner Interface 110 0 23 0 0 0 0 3 Slide Surface -1 0 0 0 0 0 0 X-centre Y-centre Radius Factor Iterations Slices M Alpha of Safety Warnings 222.9 2538.79 583.79 1.0052 4 140 0 ------------------------------------------------------------------------------- DETAILED SLICE PRINTOUT Intersection points of Slip Surface with Material Surfaces:- X Y 62.386 1977.5 658.396 2150 62.386 1977.5 468.666 2009.252 62.386 1977.5 465.540 2007.812
Slice No X-Coord Y-Coord MATERIAL Edge 113.5 1977.5 1 Mid-Base 113.75 1977.417 # 2 (Liner Interface) Edge 114 1977.333 2 Mid-Base 114.07 1977.31 # 2 (Liner Interface) Edge 114.14 1977.287 3 Mid-Base 116.133 1976.622 # 2 (Liner Interface) Edge 118.126 1975.958 4 Mid-Base 120.119 1975.294 # 2 (Liner Interface) Edge 122.112 1974.629 5 Mid-Base 124.105 1973.965 # 2 (Liner Interface)
Edge 126.098 1973.301 6 Mid-Base 128.091 1972.636 # 2 (Liner Interface) Edge 130.084 1971.972 7 Mid-Base 132.077 1971.308 # 2 (Liner Interface) Edge 134.07 1970.643 8 Mid-Base 136.063 1969.979 # 2 (Liner Interface) Edge 138.056 1969.315 9 Mid-Base 140.049 1968.65 # 2 (Liner Interface) Edge 142.042 1967.986 10 Mid-Base 144.035 1967.322 # 2 (Liner Interface) Edge 146.028 1966.657 11 Mid-Base 148.021 1965.993 # 2 (Liner Interface) Edge 150.014 1965.329 12 Mid-Base 152.007 1964.664 # 2 (Liner Interface) Edge 154 1964 13 Mid-Base 155.997 1964.281 # 2 (Liner Interface) Edge 157.994 1964.562 14 Mid-Base 159.991 1964.843 # 2 (Liner Interface) Edge 161.988 1965.123 15 Mid-Base 163.985 1965.404 # 2 (Liner Interface) Edge 165.982 1965.685 16 Mid-Base 167.979 1965.966 # 2 (Liner Interface) Edge 169.976 1966.247 17 Mid-Base 171.973 1966.528 # 2 (Liner Interface) Edge 173.970 1966.808 18 Mid-Base 175.967 1967.089 # 2 (Liner Interface) Edge 177.964 1967.37 19 Mid-Base 179.961 1967.651 # 2 (Liner Interface) Edge 181.958 1967.932 20 Mid-Base 183.955 1968.213 # 2 (Liner Interface)
Edge 185.952 1968.494 21 Mid-Base 187.949 1968.774 # 2 (Liner Interface) Edge 189.947 1969.055 22 Mid-Base 191.944 1969.336 # 2 (Liner Interface) Edge 193.941 1969.617 23 Mid-Base 195.938 1969.898 # 2 (Liner Interface) Edge 197.935 1970.179 24 Mid-Base 199.932 1970.459 # 2 (Liner Interface) Edge 201.929 1970.74 25 Mid-Base 203.926 1971.021 # 2 (Liner Interface) Edge 205.923 1971.302 26 Mid-Base 207.920 1971.583 # 2 (Liner Interface)
Edge 209.917 1971.864 27 Mid-Base 211.914 1972.145 # 2 (Liner Interface) Edge 213.911 1972.425 28 Mid-Base 215.908 1972.706 # 2 (Liner Interface) Edge 217.905 1972.987 29 Mid-Base 219.902 1973.268 # 2 (Liner Interface) Edge 221.899 1973.549 30 Mid-Base 223.896 1973.83 # 2 (Liner Interface) Edge 225.894 1974.11 31 Mid-Base 227.891 1974.391 # 2 (Liner Interface) Edge 229.888 1974.672 32 Mid-Base 231.885 1974.953 # 2 (Liner Interface) Edge 233.882 1975.234 33 Mid-Base 235.879 1975.515 # 2 (Liner Interface) Edge 237.876 1975.796 34 Mid-Base 239.873 1976.076 # 2 (Liner Interface) Edge 241.870 1976.357 35 Mid-Base 243.867 1976.638 # 2 (Liner Interface) Edge 245.864 1976.919 36 Mid-Base 247.861 1977.2 # 2 (Liner Interface) Edge 249.858 1977.481 37 Mid-Base 251.855 1977.761 # 2 (Liner Interface) Edge 253.852 1978.042 38 Mid-Base 255.849 1978.323 # 2 (Liner Interface) Edge 257.846 1978.604 39 Mid-Base 259.843 1978.885 # 2 (Liner Interface) Edge 261.841 1979.166 40 Mid-Base 263.838 1979.447 # 2 (Liner Interface) Edge 265.835 1979.728 41 Mid-Base 267.832 1980.008 # 2 (Liner Interface)
Edge 269.829 1980.289 42 Mid-Base 271.826 1980.57 # 2 (Liner Interface) Edge 273.823 1980.851 43 Mid-Base 275.820 1981.132 # 2 (Liner Interface) Edge 277.817 1981.413 44 Mid-Base 279.814 1981.693 # 2 (Liner Interface) Edge 281.811 1981.974 45 Mid-Base 283.808 1982.255 # 2 (Liner Interface) Edge 285.805 1982.536 46 Mid-Base 287.802 1982.817 # 2 (Liner Interface) Edge 289.799 1983.098 47 Mid-Base 291.796 1983.378 # 2 (Liner Interface)
Edge 293.793 1983.659 48 Mid-Base 295.790 1983.94 # 2 (Liner Interface) Edge 297.788 1984.221 49 Mid-Base 299.785 1984.502 # 2 (Liner Interface) Edge 301.782 1984.783 50 Mid-Base 303.779 1985.064 # 2 (Liner Interface) Edge 305.776 1985.344 51 Mid-Base 307.773 1985.625 # 2 (Liner Interface) Edge 309.770 1985.906 52 Mid-Base 311.767 1986.187 # 2 (Liner Interface) Edge 313.764 1986.468 53 Mid-Base 315.761 1986.749 # 2 (Liner Interface) Edge 317.758 1987.03 54 Mid-Base 319.755 1987.31 # 2 (Liner Interface) Edge 321.752 1987.591 55 Mid-Base 323.749 1987.872 # 2 (Liner Interface) Edge 325.746 1988.153 56 Mid-Base 327.743 1988.434 # 2 (Liner Interface) Edge 329.740 1988.715 57 Mid-Base 331.737 1988.995 # 2 (Liner Interface) Edge 333.735 1989.276 58 Mid-Base 335.732 1989.557 # 2 (Liner Interface) Edge 337.729 1989.838 59 Mid-Base 339.726 1990.119 # 2 (Liner Interface) Edge 341.723 1990.4 60 Mid-Base 343.720 1990.681 # 2 (Liner Interface) Edge 345.717 1990.961 61 Mid-Base 347.714 1991.242 # 2 (Liner Interface) Edge 349.711 1991.523 62 Mid-Base 351.708 1991.804 # 2 (Liner Interface)
Edge 353.705 1992.085 63 Mid-Base 355.702 1992.366 # 2 (Liner Interface) Edge 357.699 1992.646 64 Mid-Base 359.696 1992.927 # 2 (Liner Interface) Edge 361.693 1993.208 65 Mid-Base 363.690 1993.489 # 2 (Liner Interface) Edge 365.687 1993.77 66 Mid-Base 367.684 1994.051 # 2 (Liner Interface) Edge 369.681 1994.332 67 Mid-Base 371.679 1994.612 # 2 (Liner Interface) Edge 373.676 1994.893 68 Mid-Base 375.673 1995.174 # 2 (Liner Interface)
Edge 377.670 1995.455 69 Mid-Base 379.667 1995.736 # 2 (Liner Interface) Edge 381.664 1996.017 70 Mid-Base 383.661 1996.298 # 2 (Liner Interface) Edge 385.658 1996.578 71 Mid-Base 387.655 1996.859 # 2 (Liner Interface) Edge 389.652 1997.14 72 Mid-Base 391.649 1997.421 # 2 (Liner Interface) Edge 393.646 1997.702 73 Mid-Base 395.643 1997.983 # 2 (Liner Interface) Edge 397.640 1998.263 74 Mid-Base 399.637 1998.544 # 2 (Liner Interface) Edge 401.634 1998.825 75 Mid-Base 403.631 1999.106 # 2 (Liner Interface) Edge 405.628 1999.387 76 Mid-Base 407.626 1999.668 # 2 (Liner Interface) Edge 409.623 1999.948 77 Mid-Base 411.620 2000.229 # 2 (Liner Interface) Edge 413.617 2000.51 78 Mid-Base 415.614 2000.791 # 2 (Liner Interface) Edge 417.611 2001.072 79 Mid-Base 419.608 2001.353 # 2 (Liner Interface) Edge 421.605 2001.634 80 Mid-Base 423.602 2001.915 # 2 (Liner Interface) Edge 425.599 2002.195 81 Mid-Base 427.596 2002.476 # 2 (Liner Interface) Edge 429.593 2002.757 82 Mid-Base 431.590 2003.038 # 2 (Liner Interface) Edge 433.587 2003.319 83 Mid-Base 435.584 2003.6 # 2 (Liner Interface)
Edge 437.581 2003.88 84 Mid-Base 439.578 2004.161 # 2 (Liner Interface) Edge 441.575 2004.442 85 Mid-Base 443.573 2004.723 # 2 (Liner Interface) Edge 445.57 2005.004 86 Mid-Base 447.567 2005.285 # 2 (Liner Interface) Edge 449.564 2005.566 87 Mid-Base 451.561 2005.846 # 2 (Liner Interface) Edge 453.558 2006.127 88 Mid-Base 455.555 2006.408 # 2 (Liner Interface) Edge 457.552 2006.689 89 Mid-Base 459.549 2006.97 # 2 (Liner Interface)
Edge 461.546 2007.251 90 Mid-Base 463.543 2007.531 # 2 (Liner Interface) Edge 465.540 2007.812 91 Mid-Base 467.103 2008.529 # 2 (Liner Interface) Edge 468.666 2009.252 92 Mid-Base 470.640 2010.172 # 1 (Waste) Edge 472.614 2011.102 93 Mid-Base 474.588 2012.041 # 1 (Waste) Edge 476.563 2012.989 94 Mid-Base 478.537 2013.946 # 1 (Waste) Edge 480.511 2014.912 95 Mid-Base 482.485 2015.887 # 1 (Waste) Edge 484.459 2016.872 96 Mid-Base 486.434 2017.866 # 1 (Waste) Edge 488.408 2018.869 97 Mid-Base 490.382 2019.882 # 1 (Waste) Edge 492.356 2020.905 98 Mid-Base 494.330 2021.937 # 1 (Waste) Edge 496.304 2022.978 99 Mid-Base 498.279 2024.029 # 1 (Waste) Edge 500.253 2025.09 100 Mid-Base 502.227 2026.161 # 1 (Waste) Edge 504.201 2027.242 101 Mid-Base 506.175 2028.332 # 1 (Waste) Edge 508.15 2029.433 102 Mid-Base 510.124 2030.544 # 1 (Waste) Edge 512.098 2031.664 103 Mid-Base 514.072 2032.795 # 1 (Waste)
Edge 516.046 2033.936 104 Mid-Base 518.020 2035.088 # 1 (Waste) Edge 519.995 2036.25 105 Mid-Base 521.969 2037.422 # 1 (Waste) Edge 523.943 2038.605 106 Mid-Base 525.917 2039.798 # 1 (Waste) Edge 527.891 2041.003 107 Mid-Base 529.866 2042.217 # 1 (Waste) Edge 531.840 2043.443
108 Mid-Base 533.814 2044.68 # 1 (Waste) Edge 535.788 2045.928 109 Mid-Base 537.762 2047.187 # 1 (Waste) Edge 539.736 2048.457 110 Mid-Base 541.711 2049.738 # 1 (Waste) Edge 543.685 2051.031 111 Mid-Base 545.659 2052.334 # 1 (Waste) Edge 547.633 2053.65 112 Mid-Base 549.607 2054.977 # 1 (Waste) Edge 551.582 2056.316 113 Mid-Base 553.556 2057.667 # 1 (Waste) Edge 555.530 2059.03 114 Mid-Base 557.504 2060.405 # 1 (Waste) Edge 559.478 2061.792 115 Mid-Base 561.452 2063.191 # 1 (Waste) Edge 563.427 2064.602 116 Mid-Base 565.401 2066.026 # 1 (Waste) Edge 567.375 2067.463 117 Mid-Base 569.349 2068.912 # 1 (Waste) Edge 571.323 2070.374 118 Mid-Base 573.298 2071.849 # 1 (Waste) Edge 575.272 2073.337 119
Mid-Base 577.246 2074.838 # 1 (Waste) Edge 579.220 2076.352 120 Mid-Base 581.194 2077.88 # 1 (Waste) Edge 583.168 2079.421 121 Mid-Base 585.143 2080.977 # 1 (Waste) Edge 587.117 2082.546 122 Mid-Base 589.091 2084.129 # 1 (Waste) Edge 591.065 2085.726 123 Mid-Base 593.039 2087.337 # 1 (Waste)
Edge 595.014 2088.963 124 Mid-Base 596.988 2090.603 # 1 (Waste) Edge 598.962 2092.259 125 Mid-Base 600.936 2093.928 # 1 (Waste) Edge 602.910 2095.614 126 Mid-Base 604.884 2097.314 # 1 (Waste) Edge 606.859 2099.03 127 Mid-Base 608.833 2100.761 # 1 (Waste) Edge 610.807 2102.509 128 Mid-Base 612.781 2104.272 # 1 (Waste) Edge 614.755 2106.052 129 Mid-Base 616.73 2107.847 # 1 (Waste) Edge 618.704 2109.66 130 Mid-Base 620.678 2111.489 # 1 (Waste) Edge 622.652 2113.335 131 Mid-Base 624.626 2115.199 # 1 (Waste) Edge 626.600 2117.08 132 Mid-Base 628.575 2118.979 # 1 (Waste) Edge 630.549 2120.895 133 Mid-Base 632.523 2122.83 # 1 (Waste) Edge 634.497 2124.783 134 Mid-Base 636.471 2126.756 # 1 (Waste) Edge 638.446 2128.747
135 Mid-Base 640.420 2130.757 # 1 (Waste) Edge 642.394 2132.787 136 Mid-Base 644.368 2134.836 # 1 (Waste) Edge 646.342 2136.906 137 Mid-Base 648.316 2138.997 # 1 (Waste) Edge 650.291 2141.108 138 Mid-Base 652.265 2143.24 # 1 (Waste) Edge 654.24 2145.394 139 Mid-Base 655.279 2146.537 # 1 (Waste)
Edge 656.318 2147.685 140 Mid-Base 657.357 2148.839 # 1 (Waste) Edge 658.396 2150 Water force on right side = 0 at Y= 2150 Water force on left side = 0 at Y= 1977.5 First slice No. = 1 Last Slice No. = 140 There are no explicit external forces in the data set. Reinforcement Tallowable Tconnection Layer Position per unit per unit No. X1 Length Elevation width width Reinf. Soil X-Coord of Total Pore Force used Layer Mat'l Slip surface Vertical Pressure per unit No. No. Intersection Stress width Slice Width Vertical Pore Tan Alpha Tan Phi Weight TL(I) No. Stress Pressure 1 .5 9.15 0 .33325 .42447 4.57 -1102.21 2 .139 20.45 0 .33395 .42447 2.86 -689.33 3 3.986 140.49 0 .33331 .42447 560.02 -134807.1 4 3.986 376.31 0 .33335 .42447 1500.00 -361073.9 5 3.986 612.13 0 .33331 .42447 2439.96 -587337.8 6 3.986 847.95 0 .33331 .42447 3379.95 -813608.5 7 3.986 1083.77 0 .33334 .42447 4319.91 -1039869 8 3.985 1319.59 0 .33332 .42447 5259.88 -1266139 9 3.985 1555.39 0 .33335 .42447 6199.77 -1492379 10 3.985 1791.22 0 .33332 .42447 7139.81 -1718669 11 3.985 2027.04 0 .33335 .42447 8079.77 -1944921 12 3.986 2262.86 0 .33331 .42447 9019.82 -2171220 13 3.994 2412.89 0 -.14061 .42447 9637.38 -2289248 14 3.994 2477.14 0 -.14064 .42447 9893.99 -2350185 15 3.994 2541.39 0 -.14061 .42447 10150.61 -2411158 16 3.994 2605.66 0 -.14064 .42447 10407.31 -2472117
17 3.994 2669.92 0 -.14061 .42447 10663.97 -2533101 18 3.994 2734.17 0 -.14061 .42447 10920.59 -2594056 19 3.994 2798.43 0 -.14064 .42447 11177.24 -2655004 20 3.994 2862.69 0 -.14061 .42447 11433.9 -2715988 21 3.994 2926.94 0 -.14064 .42447 11690.56 -2776936 22 3.994 2991.19 0 -.14061 .42447 11947.17 -2837908 23 3.994 3055.45 0 -.14064 .42447 12203.83 -2898857 24 3.994 3119.71 0 -.14061 .42447 12460.49 -2959840 25 3.994 3183.97 0 -.14061 .42447 12717.15 -3020805 26 3.994 3248.23 0 -.14064 .42447 12973.8 -3081756 27 3.994 3312.49 0 -.14061 .42447 13230.46 -3142737 28 3.994 3376.74 0 -.14064 .42447 13487.07 -3203677 29 3.994 3440.98 0 -.14061 .42447 13743.69 -3264647 30 3.994 3505.25 0 -.14061 .42447 14000.39 -3325624 31 3.994 3569.51 0 -.14064 .42447 14257.05 -3386576 32 3.994 3633.76 0 -.14061 .42447 14513.66 -3447544 33 3.994 3698.02 0 -.14064 .42447 14770.32 -3508497 34 3.994 3762.28 0 -.14061 .42447 15026.98 -3569475
35 3.994 3826.54 0 -.14064 .42447 15283.63 -3630429 36 3.994 3890.79 0 -.14061 .42447 15540.25 -3691395 37 3.994 3955.06 0 -.14061 .42447 15796.95 -3752372 38 3.994 4019.30 0 -.14064 .42447 16053.56 -3813318 39 3.994 4083.55 0 -.14061 .42447 16310.18 -3874282 40 3.994 4147.81 0 -.14064 .42447 16566.84 -3935240 41 3.994 4212.08 0 -.14061 .42447 16823.54 -3996223 42 3.994 4276.33 0 -.14061 .42447 17080.15 -4057178 43 3.994 4340.59 0 -.14064 .42447 17336.81 -4118139 44 3.994 4404.85 0 -.14061 .42447 17593.47 -4179110 45 3.994 4469.11 0 -.14064 .42447 17850.12 -4240071 46 3.994 4533.35 0 -.14061 .42447 18106.74 -4301029 47 3.994 4597.62 0 -.14061 .42447 18363.44 -4362007 48 3.994 4661.87 0 -.14064 .42447 18620.05 -4422960 49 3.994 4726.12 0 -.14061 .42447 18876.67 -4483916 50 3.994 4790.39 0 -.14064 .42447 19133.37 -4544893 51 3.994 4854.65 0 -.14061 .42447 19390.02 -4605857 52 3.994 4918.90 0 -.14064 .42447 19646.64 -4666815 53 3.994 4983.15 0 -.14061 .42447 19903.25 -4727766 54 3.994 5047.43 0 -.14061 .42447 20160 -4788754 55 3.994 5111.68 0 -.14064 .42447 20416.61 -4849715 56 3.994 5175.92 0 -.14061 .42447 20673.22 -4910663 57 3.994 5240.18 0 -.14064 .42447 20929.88 -4971637 58 3.994 5304.44 0 -.14061 .42447 21186.54 -5032594 59 3.994 5368.69 0 -.14061 .42447 21443.15 -5093548 60 3.994 5432.97 0 -.14064 .42447 21699.9 -5154546 61 3.994 5497.21 0 -.14061 .42447 21956.47 -5215480 62 3.994 5561.48 0 -.14064 .42447 22213.17 -5276469 63 3.994 5625.70 0 -.14061 .42447 22469.7 -5337388 64 3.994 5690 0 -.14061 .42447 22726.49 -5398386 65 3.994 5754.22 0 -.14064 .42447 22983.01 -5459337 66 3.994 5818.49 0 -.14061 .42447 23239.71 -5520295 67 3.994 5882.77 0 -.14064 .42447 23496.46 -5581302 68 3.994 5947.01 0 -.14061 .42447 23753.03 -5642226 69 3.994 6011.28 0 -.14064 .42447 24009.73 -5703225 70 3.994 6075.51 0 -.14061 .42447 24266.26 -5764133 71 3.994 6139.80 0 -.14061 .42447 24523.05 -5825132 72 3.994 6204.02 0 -.14064 .42447 24779.57 -5886094 73 3.994 6268.29 0 -.14061 .42447 25036.27 -5947040 74 3.994 6332.53 0 -.14064 .42447 25292.84 -6008016 75 3.994 6396.81 0 -.14061 .42447 25549.59 -6068972 76 3.994 6461.06 0 -.14061 .42447 25806.2 -6129925 77 3.994 6525.32 0 -.14064 .42447 26062.86 -6190927 78 3.994 6589.60 0 -.14061 .42447 26319.61 -6251877 79 3.994 6653.83 0 -.14064 .42447 26576.13 -6312851 80 3.994 6718.10 0 -.14061 .42447 26832.83 -6373785 81 3.994 6782.33 0 -.14064 .42447 27089.4 -6434774 82 3.994 6846.61 0 -.14061 .42447 27346.15 -6495716 83 3.994 6910.84 0 -.14061 .42447 27602.67 -6556649 84 3.994 6975.12 0 -.14064 .42447 27859.42 -6617685 85 3.994 7039.36 0 -.14061 .42447 28115.99 -6678580 86 3.994 7103.63 0 -.14064 .42447 28372.69 -6739608 87 3.994 7167.90 0 -.14061 .42447 28629.39 -6800529 88 3.994 7232.15 0 -.14061 .42447 28886.01 -6861486 89 3.994 7296.42 0 -.14064 .42447 29142.71 -6922521 90 3.993 7360.64 0 -.14062 .42447 29397.44 -6982985 91 3.125 7363.26 0 -.46052 .42447 23017.38 -5703894 92 3.948 7306.95 0 -.46863 .52056 28850.51 -8767863 93 3.948 7252.29 0 -.47781 .52056 28634.7 -8702278 94 3.948 7194.37 0 -.48706 .52056 28406.01 -8632778 95 3.948 7133.10 0 -.49642 .52056 28164.1 -8559257 96 3.948 7068.53 0 -.50588 .52056 27909.16 -8481781 97 3.948 7000.55 0 -.51547 .52056 27640.74 -8400205
98 3.948 6929.15 0 -.52515 .52056 27358.82 -8314530 99 3.948 6854.31 0 -.53498 .52056 27063.33 -8224729 100 3.948 6775.92 0 -.54487 .52056 26753.83 -8130669 101 3.948 6694.02 0 -.55495 .52056 26430.45 -8032390 102 3.948 6608.52 0 -.56512 .52056 26092.88 -7929801 103 3.948 6519.35 0 -.57542 .52056 25740.78 -7822796 104 3.948 6426.52 0 -.58590 .52056 25374.28 -7711413 105 3.948 6329.93 0 -.59650 .52056 24992.9 -7595510 106 3.948 6229.55 0 -.60726 .52056 24596.55 -7475058 107 3.948 6125.35 0 -.61814 .52056 24185.12 -7350019 108 3.948 6017.19 0 -.62924 .52056 23758.06 -7220233 109 3.948 5905.10 0 -.64046 .52056 23315.52 -7085741 110 3.948 5789.00 0 -.65190 .52056 22857.1 -6946425 111 3.948 5668.77 0 -.66347 .52056 22382.37 -6802151 112 3.948 5544.42 0 -.67528 .52056 21891.41 -6652948 113 3.948 5415.84 0 -.68721 .52056 21383.72 -6498655 114 3.948 5282.95 0 -.69945 .52056 20859.02 -6339195 115 3.948 5145.71 0 -.71182 .52056 20317.14 -6174515 116 3.948 5004.00 0 -.72450 .52056 19757.65 -6004482 117 3.948 4857.78 0 -.73730 .52056 19180.29 -5829018 118 3.948 4706.98 0 -.75040 .52056 18584.88 -5648070 119 3.948 4551.43 0 -.76376 .52056 17970.73 -5461427 120 3.948 4391.12 0 -.77730 .52056 17337.76 -5269062 121 3.948 4225.95 0 -.79128 .52056 16685.62 -5070871 122 3.948 4055.73 0 -.80537 .52056 16013.52 -4866616 123 3.948 3880.48 0 -.81991 .52056 15321.55 -4656323 124 3.948 3700.02 0 -.83468 .52056 14609.02 -4439781 125 3.948 3514.24 0 -.84977 .52056 13875.5 -4216858 126 3.948 3323.03 0 -.86523 .52056 13120.55 -3987423 127 3.948 3126.24 0 -.88106 .52056 12343.56 -3751292 128 3.948 2923.81 0 -.89726 .52056 11544.28 -3508384 129 3.948 2715.53 0 -.91389 .52056 10721.92 -3258463 130 3.948 2501.25 0 -.93090 .52056 9875.87 -3001345 131 3.948 2280.87 0 -.94833 .52056 9005.71 -2736896 132 3.948 2054.18 0 -.96633 .52056 8110.64 -2464881 133 3.948 1821.02 0 -.98475 .52056 7190.08 -2185114 134 3.948 1581.26 0 -1.00374 .52056 6243.39 -1897411 135 3.948 1334.59 0 -1.02328 .52056 5269.47 -1601429 136 3.948 1080.96 0 -1.04337 .52056 4268.05 -1297089 137 3.948 820.04 0 -1.06409 .52056 3237.82 -983995.9 138 3.948 551.62 0 -1.08545 .52056 2178.31 -662004.1 139 2.078 311.70 0 -1.10227 .52056 647.72 -196847.1 140 2.078 104.45 0 -1.11414 .52056 217.06 -65967.22 SLICE MALPHA DELTANUM N.FORCE N.LEVER RADIUS DEL.PF Cohesion 1 .81520 -1352.0 5.6 -73.93 -567.09 -415.27 0 2 .81475 -846.0 3.5 -74.62 -567.04 -262.32 0 3 .81515 -165375.2 687.0 -76.48 -567.09 -52543.53 0 4 .81513 -442959.8 1840.1 -80.69 -567.08 -148499.6 0 5 .81515 -720519.4 2993.2 -84.88 -567.09 -254078.5 0 6 .81515 -998097.9 4146.3 -89.08 -567.09 -369383.1 0 7 .81513 -1275694 5299.6 -93.30 -567.08 -494467.6 0 8 .81515 -1553243 6452.5 -97.48 -567.09 -629059.6 0 9 .81513 -1830827 7605.7 -101.70 -567.08 -773559.6 0 10 .81515 -2108387 8758.8 -105.89 -567.09 -927493.5 0 11 .81513 -2386000 9912.1 -110.10 -567.08 -1091425 0 12 .81516 -2663550 11065.1 -114.29 -567.09 -1264681 0 13 1.04905 -2182195 9186.7 146.25 -559.60 1343574 0 14 1.04906 -2240264 9431.2 142.23 -559.60 1341456 0 15 1.04905 -2298404 9675.9 138.18 -559.60 1337070 0 16 1.04906 -2356493 9920.5 134.16 -559.60 1331026 0 17 1.04905 -2414644 10165.2 130.11 -559.60 1322690 0
18 1.04905 -2472748 10409.9 126.08 -559.60 1312531 0 19 1.04906 -2530827 10654.4 122.06 -559.60 1300573 0 20 1.04905 -2588978 10899.2 118.01 -559.60 1286304 0 21 1.04906 -2647056 11143.7 114.00 -559.60 1270407 0 22 1.04905 -2705197 11388.4 109.95 -559.60 1252177 0 23 1.04906 -2763275 11633.0 105.93 -559.60 1232342 0 24 1.04905 -2821427 11877.7 101.88 -559.60 1210161 0 25 1.04905 -2879541 12122.4 97.85 -559.60 1186193 0 26 1.04906 -2937619 12367 93.83 -559.60 1160450 0 27 1.04905 -2995771 12611.7 89.78 -559.60 1132336 0 28 1.04906 -3053838 12856.2 85.76 -559.60 1102651 0 29 1.04905 -3111980 13100.9 81.71 -559.60 1070577 0 30 1.04905 -3170105 13345.6 77.68 -559.60 1036745 0 31 1.04906 -3228182 13590.2 73.66 -559.60 1001156 0 32 1.04905 -3286324 13834.9 69.61 -559.60 963148.8 0 33 1.04906 -3344401 14079.5 65.60 -559.60 923621.4 0 34 1.04905 -3402554 14324.2 61.55 -559.60 881662.1 0 35 1.04906 -3460630 14568.8 57.53 -559.60 838196.3 0 36 1.04905 -3518772 14813.5 53.48 -559.60 792278.3 0 37 1.04905 -3576898 15058.2 49.45 -559.60 744630 0 38 1.04906 -3634965 15302.7 45.43 -559.60 695254.8 0 39 1.04905 -3693106 15547.4 41.38 -559.60 643403.3 0 40 1.04906 -3751184 15791.9 37.36 -559.60 590093 0 41 1.04905 -3809346 16036.8 33.31 -559.60 534288.3 0 42 1.04905 -3867450 16281.4 29.28 -559.60 476768.4 0 43 1.04906 -3925529 16525.9 25.26 -559.60 417550.2 0 44 1.04905 -3983680 16770.7 21.21 -559.60 355810.6 0 45 1.04906 -4041758 17015.2 17.19 -559.60 292653.8 0 46 1.04905 -4099897 17260 13.14 -559.60 226957.3 0 47 1.04905 -4158023 17504.7 9.11 -559.60 159570.8 0 48 1.04906 -4216094 17749.1 5.09 -559.60 90508.18 0 49 1.04905 -4274232 17993.9 1.04 -559.60 18876.42 0 50 1.04906 -4332323 18238.4 -2.96 -559.60 -54123.14 0 51 1.04905 -4390471 18483.2 -7.01 -559.60 -129711.3 0 52 1.04906 -4448543 18727.7 -11.03 -559.60 -206648.8 0 53 1.04905 -4506679 18972.5 -15.08 -559.60 -286192.8 0 54 1.04905 -4564814 19217.2 -19.11 -559.60 -367394.4 0 55 1.04906 -4622888 19461.7 -23.13 -559.60 -450239.5 0 56 1.04905 -4681022 19706.4 -27.18 -559.60 -535716.4 0 57 1.04906 -4739108 19950.9 -31.20 -559.60 -622499.3 0 58 1.04905 -4797252 20195.7 -35.25 -559.60 -711933.8 0 59 1.04905 -4855356 20440.3 -39.28 -559.60 -803002.4 0 60 1.04906 -4913462 20684.9 -43.30 -559.60 -895693.3 0 61 1.04905 -4971585 20929.7 -47.35 -559.60 -991060.9 0 62 1.04906 -5029683 21174.2 -51.36 -559.60 -1087688 0 63 1.04905 -5087793 21418.9 -55.41 -559.60 -1187010 0 64 1.04905 -5145938 21663.7 -59.45 -559.60 -1287953 0 65 1.04906 -5203998 21908.0 -63.46 -559.60 -1390478 0 66 1.04905 -5262146 22152.9 -67.51 -559.60 -1495743 0 67 1.04906 -5320259 22397.5 -71.53 -559.60 -1602219 0 68 1.04905 -5378375 22642.2 -75.58 -559.60 -1711432 0 69 1.04906 -5436479 22886.7 -79.60 -559.60 -1821842 0 70 1.04905 -5494582 23131.4 -83.65 -559.60 -1935008 0 71 1.04905 -5552728 23376.2 -87.68 -559.60 -2049771 0 72 1.04906 -5610795 23620.6 -91.70 -559.60 -2166071 0 73 1.04905 -5668935 23865.4 -95.75 -559.60 -2285189 0 74 1.04906 -5727015 24109.8 -99.76 -559.60 -2405428 0 75 1.04905 -5785165 24354.8 -103.81 -559.60 -2528507 0 76 1.04905 -5843267 24599.4 -107.85 -559.60 -2653122 0 77 1.04906 -5901371 24843.8 -111.86 -559.60 -2779276 0 78 1.04905 -5959517 25088.8 -115.91 -559.60 -2908291 0 79 1.04906 -6017592 25333.1 -119.93 -559.60 -3038368 0 80 1.04905 -6075724 25578.0 -123.98 -559.60 -3171336 0
81 1.04906 -6133812 25822.4 -128.00 -559.60 -3305354 0 82 1.04905 -6191953 26067.3 -132.05 -559.60 -3442285 0 83 1.04905 -6250036 26311.8 -136.08 -559.60 -3580703 0 84 1.04906 -6308169 26556.4 -140.10 -559.60 -3720647 0 85 1.04905 -6366266 26801.1 -144.15 -559.60 -3863492 0 86 1.04906 -6424390 27045.6 -148.17 -559.60 -4007368 0 87 1.04905 -6482512 27290.5 -152.22 -559.60 -4154189 0 88 1.04905 -6540618 27535.1 -156.25 -559.60 -4302484 0 89 1.04906 -6598747 27779.6 -160.27 -559.60 -4452266 0 90 1.04906 -6656421 28022.6 -164.31 -559.60 -4604568 0 91 1.08494 -5257317 21215.2 0 -583.79 0 0 92 1.12525 -7791908 25639.1 0 -583.79 0 0 93 1.12555 -7731542 25440.5 0 -583.79 0 0 94 1.12579 -7668165 25231.9 0 -583.79 0 0 95 1.12597 -7601665 25013.1 0 -583.79 0 0 96 1.12608 -7532101 24784.2 0 -583.79 0 0 97 1.12613 -7459337 24544.8 0 -583.79 0 0 98 1.12611 -7383366 24294.8 0 -583.79 0 0 99 1.12603 -7304158 24034.2 0 -583.79 0 0 100 1.12588 -7221579 23762.4 0 -583.79 0 0 101 1.12566 -7135666 23479.7 0 -583.79 0 0 102 1.12538 -7046313 23185.7 0 -583.79 0 0 103 1.12502 -6953415 22880.1 0 -583.79 0 0 104 1.12460 -6857005 22562.8 0 -583.79 0 0 105 1.12410 -6756923 22233.5 0 -583.79 0 0 106 1.12353 -6653135 21892.0 0 -583.79 0 0 107 1.1229 -6545571 21538.0 0 -583.79 0 0 108 1.12218 -6434102 21171.3 0 -583.79 0 0 109 1.12139 -6318702 20791.5 0 -583.79 0 0 110 1.12052 -6199274 20398.6 0 -583.79 0 0 111 1.11957 -6075631 19991.7 0 -583.79 0 0 112 1.11855 -5947819 19571.2 0 -583.79 0 0 113 1.11745 -5815601 19136.1 0 -583.79 0 0 114 1.11626 -5678960 18686.5 0 -583.79 0 0 115 1.11499 -5537715 18221.7 0 -583.79 0 0 116 1.11363 -5391797 17741.6 0 -583.79 0 0 117 1.11219 -5240990 17245.3 0 -583.79 0 0 118 1.11066 -5085292 16733.0 0 -583.79 0 0 119 1.10904 -4924425 16203.7 0 -583.79 0 0 120 1.10734 -4758270 15657.0 0 -583.79 0 0 121 1.10553 -4586805 15092.8 0 -583.79 0 0 122 1.10364 -4409575 14509.6 0 -583.79 0 0 123 1.10164 -4226699 13907.8 0 -583.79 0 0 124 1.09955 -4037802 13286.3 0 -583.79 0 0 125 1.09736 -3842715 12644.3 0 -583.79 0 0 126 1.09506 -3641258 11981.5 0 -583.79 0 0 127 1.09266 -3433162 11296.7 0 -583.79 0 0 128 1.09015 -3218248 10589.5 0 -583.79 0 0 129 1.08752 -2996213 9858.9 0 -583.79 0 0 130 1.08479 -2766737 9103.9 0 -583.79 0 0 131 1.08194 -2529597 8323.5 0 -583.79 0 0 132 1.07896 -2284478 7517.0 0 -583.79 0 0 133 1.07587 -2031009 6683.0 0 -583.79 0 0 134 1.07265 -1768898 5820.5 0 -583.79 0 0 135 1.06929 -1497648 4927.9 0 -583.79 0 0 136 1.06581 -1216995 4004.5 0 -583.79 0 0 137 1.06219 -926382.2 3048.2 0 -583.79 0 0 138 1.05843 -625457.8 2058.0 0 -583.79 0 0 139 1.05545 -186504.3 613.6 0 -583.79 0 0 140 1.05335 -62626.1 206.0 0 -583.79 0 0 ---------------------------------------------------------------------------- NUM = -6.034646E+08 PF = -5.812248E+07
PF is Total Moment due to Normal forces SWX = -4.52466E+08 FACTOR OF SAFETY = 1.006077 Bishop Factor of Safety = NUM! /(SWX + EQM + GridMoment - PF!) Weight Moment = -4.52466E+08 Water Moments = 0 Ext.Force Moment = 0 ----------- SWX = -4.52466E+08 0 is the moment due to the horizontal components of the active external forces, along with a minor adjustment for non-coincidence of the force locations with the centrelines of the slices they act on. The vertical components are treated as part of the slice weight. Geogrid Moment = 0 Earthquake Moment EQM =-2.054763E+08 NUM is Total of (TL(ie Top Line)/MALPHA) for all slices) Malpha values shown are for final iteration. TL for any slice is given by :- Radius ( Width ( Cohesion + Tan Fy (Vertical Stress - Pore pressure))) No. of slices used in analysis = 140 NUMJ= 1143682 WTANALPHA= -787758.7 WEIGHT= 2471621 FLAGRI=-1 HFORCE= 0 SEISMIC= 0.167 HForceGrids = 0 (NUMJ*FLAGRI) Unfactored Janbu FoS = --------------------- WTANALPHA+WEIGHT*SEISMIC*FLAGRI+WFL-WFR-HFORCE-HForcegrids*FLAGRI Unf. Janbu FoS = 0.9526559
2017 Facility Plan Modification 
Buncombe County Solid Waste Management Facility  Buncombe County, NC 
May 2017  HHNT Project No. 1401‐010‐01 

3. OPERATION PLAN UPDATES 
Below is a summary of the Operation Plan Drawings included in the Cell 7 PTC application that 
representatives of NC DEQ have requested to be reviewed.  Please note that our review of these 
drawings was not intended to confirm the accuracy of the previous consultants work, instead, this 
review was performed to determine whether or not any modifications to these plans would be 
required as a result of the proposed modification to revise the final grades in Cells 1‐6 to 3H:1V.  
These drawings include: 
OP‐1 
OP‐2 thru 9 

A summary is provided below regarding each of the drawings that where reviewed: 

Based on our review of the Operation Plan drawings prepared by CDM‐Smith as part of the 
Operation Plan (Part 5) included in the Phase IV (Cell 7) Permit to Construct Application dated April, 
2014 we do not believe any updates or modifications to these plans are required at this time.  
Drawing OP‐1 does currently list Cells 1‐5 as “inactive” but at the time these Operation Plan 
drawings were prepared, that was in fact true.  While we could modify that note, it is clear to us 
that these Operation Plan drawings were prepared for the expressed purpose of detailing the 
proposed operations that are anticipated to occur within Phase IV (Cell 7), once constructed, and 
are therefore still applicable and valid.   
HHNT is in the process of preparing Operation Plan drawings for the proposed sliver filling 
operations associated with waste placement in Cells 1‐6 at the proposed final grade of 3H:1V.  
While these plans are in progress, the first step is to obtain permitting approval from NC DEQ for 
the proposed final grading change, which is the purpose of this modified Facility Plan permit 
application.  Therefore, we would request that the Operation Plan drawings be provided to the 
Section at a later date, and under separate cover, after the permit has been issued and the 
Operation Plan drawings have been finalized.   

2017 Facility Plan Modification
Buncombe County Solid Waste Management Facility Buncombe County, NC
May 2017 HHNT Project No. 1401-010-01

4. CLOSURE AND POST-CLOSURE PLAN UPDATES

Buncombe County Solid Waste
Management Facility
Subtitle D Landfill
Phase IV (Cell 7) Permit to Construct
Application

Part 6 – Closure/Post-Closure Plan

Original Submittal Date:
April 2014
Revised: May 2014

Buncombe County,
North Carolina

i
Table of Contents

Section 1 Closure Plan
1.1 Final Cover System ..................................................................................................................................................... 1-1
1.2 Landfill Gas Collection System .............................................................................................................................. 1-2
1.3 Estimate of Largest Closure ................................................................................................................................... 1-2
1.4 Estimate of Maximum Inventory of Waste On-Site ..................................................................................... 1-2
1.5 Landfill Closure Sequence ....................................................................................................................................... 1-2
1.5.1 Determination of Closure Area ................................................................................................................. 1-5
1.5.2 Notification of Intent to Close ................................................................................................................... 1-5
1.5.3 Develop Closure Schedule .......................................................................................................................... 1-5
1.5.4 Prepare Construction Contract Documents ........................................................................................ 1-5
1.5.5 Develop Closure Schedule .......................................................................................................................... 1-5
1.5.6 Selecting a General Contractor ................................................................................................................. 1-5
1.5.7 Securing Borrow Material for Landfill Cover ..................................................................................... 1-5
1.5.8 Certification of Closure Construction .................................................................................................... 1-5
1.5.9 Record Notation to Deed ............................................................................................................................. 1-6
1.6 Financial Assurance ................................................................................................................................................... 1-6
Section 2 Post-Closure Plan
2.1 Maintenance and Monitoring Activities............................................................................................................ 2-1
2.1.1 Final Cover System ........................................................................................................................................ 2-1
2.1.2 Leachate Collection System........................................................................................................................ 2-2
2.1.3 Groundwater Monitoring Wells ............................................................................................................... 2-2
2.1.4 Landfill Gas Monitoring and Control System ..................................................................................... 2-3
2.2 Erosion and Sedimentation Control System ................................................................................................... 2-3
2.3 Certification of Post-Closure .................................................................................................................................. 2-3
2.4 Name of Individual Responsible for Post-Closure Maintenance of the Site ..................................... 2-4
2.5 Planned Use of Landfill After Closure ................................................................................................................ 2-4
2.6 Financial Assurance ................................................................................................................................................... 2-4

1-1
Section 1
Closure Plan
Rule .1617 (a)(1)(E) of the North Carolina Solid Waste Regulation Section 15A NCAC 13B .1600,
requires municipal solid waste landfill (MSWLF) owners/operators to prepare a closure plan that
describes the steps necessary to partially close a MSWLF at any point during its active life as well as
the steps necessary to facilitate final closure. Partial closure refers to the closure of a landfill phase,
while final closure is the closure of an entire landfill. In providing this information, the closure plan
will assist the County towards achieving the goals of closure implementation, which are: to prevent
exposure of the disposed solid waste, minimize leachate generation, and control landfill gas in order to
protect public health and the environment. Specifically, this closure plan establishes: design criteria
for the closure cap system and the landfill gas collection system, a closure sequence and construction
schedule, construction cost estimates, and other important information relating to closure. This plan
was prepared in accordance with Rule .1629.
1.1 Final Cover System
In accordance with Rule .1629 (b)(1)(A), the final cover system has been designed to minimize the
amount of storm water infiltration into the landfill and to resist erosive forces. The final cover system
consists of an erosion layer, protective soil layer, drainage layer, barrier layer, and gas venting layer.
The multi-layered cap system will provide a permeability less than or equal to the bottom liner system
of the landfill.
The cap system will consist of the following layers (listed from top to bottom):
A six-inch Erosion (Vegetative Soil) Layer consisting of soil capable of supporting native plant
growth;
An 18-inch Protective Soil Layer to prevent damage due to freezing or puncture to the Drainage
and Barrier Layers;
A Drainage Layer consisting of a geocomposite. The geocomposite is designed to horizontally
drain storm water that has percolated through the Erosion and Protective Soil Layers in order
to prevent the build-up of water over the Barrier Layer (thus minimizing infiltration);
A Barrier Layer consisting of a geomembrane; and
A Gas Venting Layer placed over a compacted soil subgrade.
Due to the highly elastic nature of the geomembrane, the final cover system will accommodate the
differential settlement during the post-closure period. Detail A on Sheet EP-12 provides a detail of the
final cover system.

Section 2 • Post-Closure Plan

1-2
1.2 Landfill Gas Collection System
Per Rule .1627 (c)(3)(B) a gas collection system will be installed to minimize uplift pressure exerted
on the final cover system. To prevent uplift of the closure cap, horizontal gas collection trenches and
vertical gas wells will be used in conjunction with a gas venting layer below the closure cap
geomembrane.
The horizontal gas collection trenches consist of perforated plastic pipe surrounded by a clean gravel
backfill. Near the surface of the closure cap, a bentonite seal and synthetic boot will be installed
around the pipe to prevent storm water infiltration. The length of the trenches will vary from
elevation to elevation with the longest trenches positioned near the bottom of the landfill. Figure 1-1
provides a section detail of the horizontal collection trench design. Generally, the spacing between
trenches will be 100-feet horizontal and 30-feet vertical.
As with the horizontal gas collection trenches, a bentonite seal and synthetic boot will be installed
around the vertical gas well to prevent storm water infiltration. The depth of the vertical gas wells
will extend from final grade to within 15 feet of the bottom liner. Figure 1-2 provides a section detail
of the vertical gas well design. The exact location of the vertical gas wells will be determined at the
time of closure. Generally, one vertical well per acre is anticipated to be installed.
Also, negative pressure will be induced in the leachate collection system to eliminate formation of
deep gas pockets. The horizontal gas collection trenches, vertical gas wells, and the leachate collection
system will be connected to a gas header that will be installed along the perimeter of the landfill that
will deliver the gas to the flare station/LFTE facility where the gas will be combusted.
1.3 Estimate of Largest Closure
The construction of the landfill will occur in 6 phases, with each phase providing approximately 5
years of capacity. Existing Phases I and III (Cells 1 through 6) are a total of 56 acres, whereas Phase IV
(Cell 7) is approximately 13 acres. Thusly, Phases I through IV would be the largest closure to date,
covering an area of approximately 69 acres.
1.4 Estimate of Maximum Inventory of Waste On-Site
The maximum amount of waste that is expected to be landfilled at the Buncombe County Subtitle D
Landfill through final build-out was calculated using the Earthworks Module of Softdesk. The total
gross airspace available between the top of base liner protective cover to proposed top of
intermediate cover is approximately 11,804,000 cubic yards. This volume is available for waste and
intermediate and daily cover.
1.5 Landfill Closure Sequence
The development of the landfill will be integrated so that one phase will be in operation while another
phase is being constructed. Additionally, closure activities may be initiated in phases. Although not
mandatory, the County may elect to complete a partial closure for an area or may complete a final
closure at the end of operations. The steps for implementing the closure process are described in the
following subsections. The steps are the same for partial closure and final closure.
Section 2 • Post-Closure Plan

1-5

1.5.1 Determination of Closure Area
The County will determine the location and acreage of areas to be closed. Closure procedures should
not be instituted until an adequate area (approximately 10 acres or more) of the landfill has reached
final grade. An estimate of landfill area that has reached final grade should be determined periodically
by the surveyor for the site during the active life of the facility.
1.5.2 Notification of Intent to Close
Per Rule .1627(c)(4), once the County has determined that an area will be closed, a Notice of Intent to
Close must be placed in the operating record and the Solid Waste Section (SWS) must be notified of
the action, including location, acreage, and scheduling of the closure activities. The final cover design,
area to be closed, and scheduling of closure activities presented in this Permit Application shall be
reviewed and updated as necessary.
1.5.3 Develop Closure Schedule
The County will prepare a schedule for bidding and construction of the closure activities. Per Rule
.1627(c)(6), closure activities must be completed within 180 days of beginning closure activities
unless the County gains approval from the SWS by demonstrating that the construction period, by
necessity, will require an extended schedule and that measures to protect human health and the
environment have been implemented in the interim.
1.5.4 Prepare Construction Contract Documents
For the purpose of bidding, construction documents will be prepared for the area to be closed. The
bidding documents will allow contractors to estimate the quantity of materials needed to properly
implement the closure plan, as well as estimating the construction costs.
1.5.5 Develop Closure Schedule
Once the SWS has reviewed and commented on the closure schedule, the County will prepare a final
schedule for bidding and construction of the closure activities.
1.5.6 Selecting a General Contractor
After receiving sealed bids, a contractor will be awarded the job of constructing the final cover
according to the approved closure plan. The contractor will be required to complete all closure
activities within 180 days of beginning such activities, or as otherwise approved by the SWS.
1.5.7 Securing Borrow Material for Landfill Cover
The material to be used for construction of the closure cap system will be obtained from on-site
sources. Once usable on-site material has been exhausted, borrow material will be obtained from off-
site sources.
1.5.8 Certification of Closure Construction
Per Rule .1627(c)(7), the project engineer shall provide certification at the completion of construction
to verify that closure has been completed in accordance with the closure CQA plan. The County shall
place the certification in the operating record and forward a copy of the certification to the SWS.
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1.5.9 Record Notation to Deed
Per Rule .1627(c)(8), after final closure of the property, a notation will be placed on the deed to the
property stating that the property was used as a landfill facility, and its use is restricted under the
closure plan approved by the SWS.
Closure Sequence
Activity Process Date
Determination of Closure Area and Initiate Closure
Process
No later than 30 Days after the final receipt of
waste
Notification of Intent to Close Once an area has been determined to be closed
Develop Closure Schedule for Closure Activities -
Prepare Construction Contract Documents -
Develop Closure Schedule Once the SWS has commented on the closure
schedule
Select a General Contractor After receiving sealed bids
Closure Construction Closure activities must be completed within 180
Days of beginning closure activities or as
otherwise approved
Certification of Closure Construction At completion of construction
Record Notation to Deed After final closure of property

1.6 Financial Assurance
Per Rule .1629 (b)(3), a detailed cost estimate based on current costs has been prepared for closure of
the largest active area of the landfill facility at any time during the life of the facility and is provided in
Table 1-1. A copy of the cost estimate has been placed in the operating record. The cost estimate will
be annually adjusted to account for inflation and any changes in conditions at the facility or in the
design. If conditions call for a reduction in the amount to be financially assured, approval of the SWS
must be obtained prior to officially reducing the amount.
Quantity Unit Cost Total
Final Cover System (Phases I through IV)
Grade Intermediate Cover 69 ac $ 2,000.00 $ 138,000
Cap System Components (top to bottom):
a. 6-inch Thick Vegetative Layer 55,660 cy $ 20.00 $ 1,113,200
b. 18-inch Thick Protective Cover 166,980 cy $ 17.00 $ 2,838,660
c. Stormwater Geocomposite Drainage
Net
333,960 sy $ 7.00 $ 2,337,720
d. 40-mil Textured LLDPE
Geomembrane
333,960 sy $ 6.00 $ 2,003,760
e. GasVenting Geocomposite Drainage
Net (13 acres only, Cell 7 at 3:1)
62,920 sy $ 7.00 $ 440,440
Temporary Erosion Control 69 ac $ 1,000.00 $ 69,000
Permanent Erosion Control
Diversion Berms/Downdrains 69 ac $ 35,000.00 $ 2,415,000
Landfill Gas Management
Vertical Gas Wells (69 @ Avg. Depth of 75’) 5,175 vf $ 125.00 $ 646,875
Horizontal Gas Collection Trenches 6 ea $ 50,000.00 $ 300,000
Surveys 69 ac $ 500.00 $ 34,500
Final Landscaping
Seeding, Fertilizing & Mulching 69 ac $ 3,000.00 $ 207,000
Subtotal $ 12,544,155
Bonds and Mobilization/Demobilization (5% of
Subtotal) $ 627,208
Engineering Services, CQA/CQC (12% of
Subtotal) $ 1,505,299
Contingency (25% of Subtotal) $ 3,136,039
TOTAL $ 17,812,700
COST PER ACRE 258,155$
Table 1-1
Closure Cost Estimate
Buncombe County Subtitle D Landfill
Buncombe County, North Carolina
May 2014

2-1
Section 2
Post-Closure Plan
Rule .1617(a)(1)(E), of the North Carolina Solid Waste Regulation Section 15A NCAC 13B .1600,
requires owners/operators of municipal solid waste landfill (MSWLF) units to prepare a post-closure
plan. The purpose of the plan is to provide the necessary information for preserving the integrity of
the landfill facility in its post-closure life. This post-closure plan specifically addresses maintenance
activities for the closure cap, landfill gas control system, leachate collection system, groundwater
monitoring wells, and erosion and sedimentation control system. This plan also addresses
certification and financial assurance requirements.
Post-closure care will begin immediately following final closure of the landfill. Post-closure care may
be decreased from the minimum time period of 30 years specified in the regulations if the County can
demonstrate that the reduced period will pose no threat to human health or the environment.
However, the Solid Waste Section (SWS) reserves the right to increase the post-closure care period if
it is deemed necessary to protect human health and the environment.
2.1 Maintenance and Monitoring Activities
Per Rule .1629 (c)(1), post-closure maintenance and monitoring activities for the Subtitle D Landfill
will include the activities discussed in the following sections.
2.1.1 Final Cover System
Per Rule .1627 (d)(1)(A), maintaining the integrity and effectiveness of the cap system is required.
Inspection of the final cover system will take place quarterly and encompass the entire landfill. Items
of concern to be noted by the inspector include but are not limited to: signs of erosion (ruts, sediment
deposits, etc.), patches of stressed or dead vegetation, animal burrows, recessed areas or ponding,
upheaving, leachate seepage stains and/or flowing leachate, cracks in the cap, damaged gas vents and
tree saplings (especially species with tap roots). Following each inspection, a summary report of the
condition of the cover and the items of concern should be recorded in the post-closure log book of the
facility. Areas that require further attention should be photographed and delineated on a map of the
facility. These items should also be entered in the log book. Since post-closure inspection personnel
will most likely change during the post-closure period, the post-closure log book should be kept in a
standardized format that allows for new inspection personnel to easily review the results of past post-
closure inspections of the site.
Action should be taken immediately to address any items of concern identified during the inspection.
Obvious repair items should be performed under the supervision of the post-closure maintenance
manager. If an item of concern requires further study to determine a course of action, the engineer
responsible for closure design should be contacted for consultation.
As part of general maintenance, the vegetative cover should be mowed at least twice a year to
suppress weed and brush growth. If vegetative cover is not adequate in any particular area, soil
amendments should be applied as necessary and the area re-seeded in order to re-establish
vegetation. Insecticides may be used to eliminate insect populations that are detrimental to the
Section 2 • Post-Closure Plan

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vegetation. Animal burrows and eroded or depressed areas should be filled in with compacted soil
and reseeded.
2.1.2 Leachate Collection System
Per Rule .1627 (d)(1)(B), maintenance of the leachate collection system is required. Inspection of the
accessible items of the leachate collection system (ie. clean-outs, pond, and pump stations) will be
made on a quarterly basis. Inspection of the collection lines will be performed concurrent with the
annual cleaning service. As part of the quarterly inspection the leachate holding pond will be
inspected for damage to the liner system. Depending on seasonal conditions, the pond may be drained
so that a thorough inspection may be made (a complete inspection should be made at least once a
year). The inspector should survey the pond for items of damage such as tears in the protective layer
and/or liner, heaving, and exposed liner in the anchor trench. The outside slope of the pond should be
inspected for leachate seepage. Signs of leachate seepage may include damage to vegetation, staining
of the soil and vegetation, or actual leachate flow.
The pump stations and flow meter vault should be inspected quarterly by a qualified inspector who is
knowledgeable in the construction and operation of pump stations and flow meters. The inspector
should manually operate each pump to ensure that they are working properly. The high and low level
alarms should be checked at this time, and the overall condition of the wiring and support structures
should be inspected also. The flow meter calibration shall be checked (and scheduled for recalibration
as required) quarterly and flow meter records shall be monitored and placed in the post-closure log
book. The pump control panel shall be fully inspected at the same time, to ensure proper alarm
operations, reset functions, and normal operations performance. Run time readings shall be recorded
for each pump. A summary report of the condition of the leachate pond, pump station and metering
facilities should be recorded in the post-closure log book along with photographs of any items of
concern.
The clean-outs should be inspected for damage on a quarterly basis. The protruding portion of each
clean-out should be checked for damage and the cap should be checked for proper operation.
If problems with the leachate collection system are discovered, or abnormally high or low flows are
recorded from the pump station, assessment and/or repairs should begin immediately.
All piping of the leachate collection system will be pressure cleaned and flushed annually to remove
the build-up of biological growth and sediments.
2.1.3 Groundwater Monitoring Wells
Per Rule .1627 (d)(1)(C), maintenance of the groundwater monitoring wells is required. Inspection of
the ground water monitoring wells will take place semi-annually during sampling events. The
inspection will consist of verifying the condition of the monitoring wells to ensure that they are
providing representative samples of the ground water. The inspector should note the following:
1) The total depth of the well should be recorded every time a water sample is collected or a water
level reading is taken to check if sediment has accumulated at the bottom. If sediment build-up
has occurred, the sediment should be removed by pumping or bailing.
2) If turbid samples are collected from a well, redevelopment of the well will be necessary.
Section 2 • Post-Closure Plan

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3) The above-ground protective casing should be inspected for damage. The protective casing should
be of good structural integrity and free of any cracks or corrosion. The lockable cover and lock
should also be checked at this time.
4) The surface seals should be inspected for settling and cracking. If the seal is damaged in any way,
the seal should be replaced.
5) The well casing and cap should be inspected. The casing and cap should be of good structural
integrity and free of any cracks or corrosion. Any debris should be removed from around the cap
to prevent it from entering the well.
The condition of the ground water monitoring system should be recorded in the post-closure log book
following each sampling event. Monitoring of the groundwater wells shall be conducted as described
in the groundwater monitoring plan.
2.1.4 Landfill Gas Monitoring and Control System
Per Rule .1627 (d)(1)(D), maintenance of the landfill gas monitoring system is required. Inspection of
the landfill gas monitoring and control system should take place at least quarterly. The inspection
should consist of verifying the condition and operation of the vents, collection well, and monitoring
wells. The full depth of all vents, collection wells, and monitoring wells should be checked for
blockage that may be caused by settlement or cracks in the casing. The summary of each inspection of
the landfill gas monitoring and control system should be recorded in the post-closure log book along
with photographs of any items of concern.
Testing of the monitoring wells and on-site buildings shall be conducted as described in the
monitoring plan provided in the Operation Plan.
If any vents or wells are not properly working, they should be flushed and pressure cleaned. If all
attempts to repair a vent or well are unsuccessful, a replacement will be installed.
2.2 Erosion and Sedimentation Control System
Inspection of the erosion and sedimentation control system should occur semi-annually and after
major storm events. During each inspection, the elements of the system including ditches, pipes,
ponds, and inlet/outlet structures should be checked for obstructions and damage. The ditches should
be inspected for obstructions, erosion of side slopes, loss of vegetative cover, shifting of riprap,
excessive buildup of sediment, or any other item that may prevent the proper functioning of the ditch.
Drainage piping should be checked for blockages and the inlets/outlets should be inspected for
undercutting and rutting. The sediment level in the detention ponds should be measured to
determine if removal is required. The condition of the riser/barrel should be checked to ensure that
adequate gravel surrounds the riser and that the barrel is not filled with sediment. The berms of each
pond should be inspected for stability. Following each inspection, a summary report should be
entered in the post-closure log book along with photographs of any items of concern.
Maintenance and/or repairs should be performed as prescribed by the inspectors review.
2.3 Certification of Post-Closure
Following completion of the post-closure care period, a certification verifying that post-closure care
was performed in accordance with the post-closure plan and signed by a registered professional
Section 2 • Post-Closure Plan

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engineer will be made part of the operating record. The County will notify the SWS that the
certification has been placed in the operating record.
2.4 Name of Individual Responsible for Post-Closure
Maintenance of the Site
Mr. Jon Creighton of Buncombe County will be responsible for operations and maintenance of the site
during the post-closure period. Mr. Creighton can be reached at the following address:
Buncombe County
Planning and Development
46 Valley Street
Asheville, NC 28801
828-250-4830
Mr. Creighton most likely will not be employed with Buncombe County throughout the entire 30 year
post-closure period. A new individual will be appointed at the time Mr. Creighton's employment with
the County ends.
2.5 Planned Use of Landfill After Closure
There are no planned uses for the landfill site after closure. The property will remain County
property, maintained by the County, with public access prohibited.
2.6 Financial Assurance
The County will submit a financial assurance package to SWS in accordance with the criteria set forth
under Rule .1628. A detailed cost estimate for post-closure care has been prepared and is provided
herein (Table 2-1) and a copy has been placed in the operating record. The cost estimate is based on
30 years of post-closure care. Each year, the estimate will be adjusted for inflation and any changes to
the activities of post-closure care.
In June 2011, Session Law 2011-262 reduced the potential assessment and corrective action (PACA)
amount from a minimum of three million dollars to two million dollars. The SWS provided verbal
direction stating that post-closure activities as previously included in PACA cost estimates could no
longer be included there and had to be included in post-closure cost estimates. In a letter from Ed
Mussler dated August 12, 2013(see attached), PACA amounts do not require a cost estimate but must
present a minimum of two million dollars for the facility.
Therefore, PACA equates to $2,000,000.
Quantity Unit Cost Total
Administration/Inspection/Recordkeeping
Project Engineer (84 hrs/yr @ $100/hr) 30 yr $ 8,400 $ 252,000
Technician (68 hrs/yr @ $60/hr) 30 yr $ 4,080 $ 122,400
Clerical (48 hrs/yr @ $50/hr) 30 yr $ 2,400 $ 72,000
Monitoring
20 Groundwater Monitoring Wells Sampled and
Analyzed Semi-Annually for 30 years 1200 events $ 750 $ 900,000
1 Surface Water Locations Sampled and Analyzed
Semi-Annually for 30 years 60 events $ 750 $ 45,000
12 Landfill Gas Wells Sampled and Analyzed
Quarterly for 30 years 1440 events $ 500 $ 720,000
Maintenance
Fencing, Gates, Signs, etc. 30 yr $ 500 $ 15,000
Access Roads 30 yr $ 2,000 $ 60,000
Mowing ($100 per acre, 69 acres) 30 yr $ 6,900 $ 207,000
Stormwater Structures 30 yr $ 2,000 $ 60,000
Leachate Collection and Storage 30 yr $ 5,000 $ 150,000
Final Cover System Maintenance ($400 per acre,
69 acres)30 yr $ 27,600 $ 828,000
Groundwater and Gas Monitoring Wells 30 yr $ 1,500 $ 45,000
Leachate Closeout
Cleanout and Demo Leachate Pond 1 ls $ 300,000 $ 300,000
Fees
Annual Permit Fee 30 yr $ 1,000 $ 30,000
Subtotal $ 3,806,400
Contingency (15%) $ 570,960
TOTAL $ 4,377,360
ANNUAL COST 145,912$
Table 2-1
Post-closure Cost Estimate
Buncombe County Subtitle D Landfill
Buncombe County, North Carolina
May 2014