Microsoft Outlook - Memo Style · The Design Report utilizes information that is contained in the Hydrogeologic and Geotechnical Investigation Report prepared for the landfill expansion

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Blue, Karen

From: Arjmandi, MasoudSent: Wednesday, April 11, 2018 4:06 PMTo: Blue, KarenCc: Cusher, AnnetteSubject: FW: Upper SouthwestAttachments: USARSWMD Class 1 Landfill PMA Resubmittal-lp-04.11.18.pdf; Permit Modification

Form-Revised.pdf; Design Report-04.09.18.pdf

From: Lance Powell [mailto:[email protected]]Sent: Wednesday, April 11, 2018 3:56 PM To: Arjmandi, Masoud Cc: 'rebecca hosey' Subject: Upper Southwest

Masoud,

The attached information is being submitted on behalf of the Upper Southwest Arkansas Regional Solid WasteManagement District. I am going to send the Permit Drawings in a separate email due to file size.

Thanks,

Lance Powell, P.E.MemberCIVIL ENGINEERING ASSOCIATES, LLC2114 East Matthews AvenueJonesboro, Arkansas 72401

Phone: (870) 972 5316Fax: (870) 932 0432Mobile: (870) 243 9400

Recd Digitally

AFIN:_________________________

PMT#:_________________________ SW

DOC ID#:______________________ MD

TO:___________________________

By bluek at 7:18 am, Apr 12, 2018

31-00107

0265-S1-R1

73635

AC>FILE

2114 East Matthews Avenue Jonesboro, Arkansas 72401 870-972-5316 Fax 870-932-0432

CONWAY JONESBORO POPLAR BLUFF

April 11, 2018 Arkansas Department of Environmental Quality Office of Land Resources Attn: Mr. Masoud Arjmandi 5301 Northshore Drive North Little Rock, AR 72218 SUBJECT: Permit Modification Application Proposed Class 1 Landfill Expansion

Upper Southwest Arkansas Regional Solid Waste Management District Solid Waste Permit Number 0265-S1-R1, AFIN 31-00107

Dear Mr. Arjmandi, As requested by the Upper Southwest Arkansas Regional Solid Waste Management District, Civil Engineering Associates, LLC has revised the bottom grading plan of the Permit Drawings previously submitted with the above-referenced permit modification application. Specifically, the elevations of the bottom grading plan associated with Cell 1 and Cell 2 have been raised as shown in the enclosed, revised Permit Drawings. In addition, the enclosed Permit Modification Application form and Design Report have been revised to reflect the changes made to the Permit Drawings. If you have any questions, please do not hesitate to contact our office. Sincerely, CIVIL ENGINEERING ASSOCIATES, LLC Lance Powell, P.E. Project Manager Enclosures cc: Max Tackett (Without Enclosures)

Permit Modification FormForm:05APPLM.WPDPage 1

DEPARTMENT OF ENVIRONMENTAL QUALITYSolid Waste Management Division

PERMIT MODIFICATION APPLICATION

Note: This modification application is to be used for all modifications to solid waste disposal andprocessing facilities. The Department will classify this modification as major or minor in accordancewith the provisions of Section 22.308 of Regulation 22. Major modifications will be subject to theprovisions of Regulation 8.

I. FACILITY TYPE

X Class 1 Landfill Class 3N Landfill Class 3C Landfill

Class 3T Landfill Class 4 Landfill Transfer Station

Composting Facility Solid Waste Material Recovery Facility

II. FACILITY IDENTIFICATION

Facility Name:USARSWMD Class 1 Landfill Permit Number: 0265-S1-R1 CSN: 31-00107

Address: 319 Landfill Road

City: Nashville State: Arkansas Zip: 71852

County: Howard Telephone Number: (870) 845-2866 Fax: (870) 845-2907

III. APPLICANT(Must be permit holder)

Facility Name:Upper Southwest Arkansas Regional Solid Waste Management District (USARSWMD)

Address: 319 Landfill Road

City: Nashville State: Arkansas Zip: 71852

Contact Person: Max Tackett Phone No.: (870) 845-2866


PERMIT HISTORY (Complete for each permit and modification to date)

Number Date Issued

Permit Number: 0265-S December 18, 1992

Modification #1: 0265-S1-R1 August 27, 1993

Modification #2:

Modification #3:

Modification #4:

MODIFICATION DESCRIPTION(Complete each part below as it applies to this modification - if an item doesn't apply, mark it "N/A")

CHANGE IN PERMITTED CAPACITY (Specify whether yards or tons)

Original Cubic Yards 3,339,824 (This includes the volume of solid waste and any daily or intermediate soil cover)

Modified Cubic Yards 5,664,873

Cubic Yards Increase (Decrease) 2,325,048

SITE LIFE & SERVICE AREA

Current Service Area The USARSWMD Class 1 Landfill currently serves the entire

district with the exception of the City of Hope.

Current Tons per year through the gate 92,154.47 (2016) (tons/ year)

Current Landfill Utilization Rate 148,056 (2016) (cu. yards/ year)

Estimated remaining site life (after this modification) 19.4* years

*Based on an October 2017 survey of the landfill

CHANGE IN PERMITTED DISPOSAL ACREAGE

Original Site Acres 40.29

Modified Site Acres

Site Acres Increase (Decrease)

0265-S1-R1 July 25, 2012

58.28

18


CHANGE IN OPERATING PROCEDURES (Provide brief description of each proposed modification)

All facility operating documents have been updated to comply with Arkansas Pollution Control

CHANGE IN FACILITY DESIGN (Provide brief description of each proposed modification)

The facility design has been updated to comply with Arkansas Pollution Control and Ecology

Commission Regulation No. 22.

REASON FOR MODIFICATION (Check one or specify below)

Change in Regulation

Additional Site Life X

Improve Site Operations

Correct Past Violation

Other (Specify)

and Ecology Commission Regulation No. 22.


DRAWING REVISIONS

(Identify below each drawing that was revised or added as a result of this modification. Each revisedor added drawing should be included as an attachment to this application.)

Drawing Number Date Revision #Title

See Section 20 of the Permit Modification Application 1-17

OPERATING NARRATIVE REVISIONS

(Identify below each change to the operating narrative as a result of this modification. Revisednarrative pages should be included as an attachment to this application. Deletions from the previousnarrative should be indicated by strikeout, additions should be redlined.)

Page # Change Description NA NA

SUPPLEMENTAL DATA SUBMITTED

(Any report, study, data, information, etc. that was not part ofprevious permit documents should ~e identified below. In addition, any data identified below should be included as an attachment to thls application.

Description

None of the sections of this permit modification application were part of the previous permit

documents.

SIGNATURE AND CERTIFICATION

(The application should be signed by an authorized representative of the applicant as well as the Consultant that prepared this application. By signing below, the representatives certify that all the information in this modification is accurate and truthful.)

Max Tackett

/

Signature Typed Name

Executive Director z..-

DESIGNREPORT

UPPERSOUTHWESTARKANSASREGIONAL SOLIDWASTEMANAGEMENTDISTRICT CLASS1LANDFILL SOLIDWASTEPERMITNO.0265S1R1 AFINNO.3100107

January2018(RevisedApril2018) PreparedFor: UpperSouthwestArkansasRegional

SolidWasteManagementDistrict319LandfillRoadNashville,Arkansas71852(870)8452866PreparedBy:

CIVILENGINEERINGASSOCIATES,LLC 2114EastMatthewsAvenue Jonesboro,Arkansas72401 (870)9725316 Fax:(870)9320432

Upper Southwest Arkansas Regional Class 1 Landfill Solid Waste Management District Design Report

Civil Engineering Associates, LLC i January 2018

ENGINEERS CERTIFICATION

I certify to the best of my professional judgment that this document and all attachments properly adhere to established, sound engineering practices. This certification is contingent on the fact that all information supplied to the signatory authority, up to the date of this certification, is unquestionably accurate and was provided in good faith.

_______________________________________________ April 9, 2018 Lance Powell, P.E. Date of Certification Arkansas Professional Engineer Registration Number 12976


Civil Engineering Associates, LLC ii January 2018

TABLE OF CONTENTS ENGINEERS CERTIFICATION ................................................................................................... I1.0 INTRODUCTION .................................................................................................................... 12.0 FACILITY DESIGN ................................................................................................................. 2

2.1 BOTTOM LINER SYSTEM ................................................................................................ 22.1.1 Subgrade Surface ........................................................................................................... 22.1.2 Compacted Clay Liner ................................................................................................... 32.1.3 60-mil HDPE Geomembrane ......................................................................................... 32.1.4 General Installation and Operational Considerations .................................................... 4

2.1.4.1 Construction Stresses .............................................................................................. 42.1.4.2 Climate Conditions ................................................................................................. 42.1.4.3 Operational Stresses ............................................................................................... 5

2.2 LEACHATE COLLECTION SYSTEM DESIGN ............................................................... 52.2.1 Leachate Collection System Lateral Drainage Layer .................................................... 62.2.2 Leachate Collection System Effectiveness And Clogging Potential ............................. 62.2.3 Leachate Collection Pipe Design ................................................................................... 62.2.4 Leachate Manhole/Riser Design .................................................................................... 72.2.5 Leachate Pumping Systems ........................................................................................... 72.2.6 Leachate Storage Tanks ................................................................................................. 72.2.7 Safety and Maintenance Features .................................................................................. 72.2.8 Secondary Containment Outside Lined Areas ............................................................... 82.2.9 Leachate Disposal .......................................................................................................... 8

2.3 FINAL COVER SYSTEM ................................................................................................... 82.3.1 Overview of Final Site Completion Plan ....................................................................... 82.3.2 Regulatory Requirements .............................................................................................. 82.3.3 Final Cover System Components ................................................................................... 9

2.3.3.1 Foundation Layer ................................................................................................... 92.3.3.2 Compacted Clay Barrier Layer .............................................................................. 92.3.3.3 Geomembrane Liner ............................................................................................. 102.3.3.4 Geocomposite Layer ............................................................................................. 102.3.3.5 Vegetative Cover Layer ........................................................................................ 102.3.3.6 Vegetation ............................................................................................................. 10

2.3.4 Performance Evaluation of Selected Design ............................................................... 112.3.4.1 Infiltration ............................................................................................................. 112.3.4.2 Stability ................................................................................................................. 112.3.4.3 Erosion Control .................................................................................................... 11

2.4 SURFACE WATER CONTROL ....................................................................................... 122.5 EARTHWORK ................................................................................................................... 12

2.5.1 Landfill Construction Soil Needs ................................................................................ 122.5.2 Landfill Operational Soil Needs .................................................................................. 132.5.3 Available Soil Material ................................................................................................ 132.5.4 Soil Balance ................................................................................................................. 13

2.6 WASTE CAPACITY AND SITE LIFE ............................................................................. 14


Civil Engineering Associates, LLC iii January 2018

LIST OF APPENDICES APPENDIX A GRI Standards for Geomembranes APPENDIX B Anchor Trench Calculations APPENDIX C Help Model Calculations APPENDIX D Geotextile Clogging Calculations APPENDIX E Pipe Crushing Calculations APPENDIX F Potential Seismic Impact Analysis APPENDIX G Surface Water Control Calculations APPENDIX H Waste Volume Calculations


Civil Engineering Associates, LLC 1 January 2018

1.0 INTRODUCTION

The Upper Southwest Arkansas Regional Solid Waste Management District (USARSWMD) currently owns, operates, and maintains a Class 1 landfill located near Nashville, Arkansas. The landfill facility consists of approximately 348 acres. This Design Report presents the design criteria for the landfill and includes a discussion of the engineering calculations performed to support the proposed modifications to the facility design and a summary of the facility design. The Design Report utilizes information that is contained in the Hydrogeologic and Geotechnical Investigation Report prepared for the landfill expansion. The landfill expansion involves approximately 43.5 acres located adjacent to the active waste disposal site in the South half of the Southwest quarter of Section 12 and the North half of the North half of Section 13, Township 8 South, Range 27 West, Howard County, Arkansas.



2.0 FACILITY DESIGN

The following information summarizes the design of the facility and provides associated technical data and calculations. The analyses, design calculations, and demonstrations presented herein were conducted in accordance with Arkansas Regulation 22. This includes a discussion of the methodologies used and results obtained from engineering analyses pertaining to all components of the design associated with the proposed expansion.

2.1 BOTTOM LINER SYSTEM

In accordance with Sections 22.424 and 22.428 of Arkansas Regulation 22, the bottom liner system associated with the facility has been designed and will be constructed using a composite liner system. The purpose of the composite liner system is to contain the waste mass while preventing leachate infiltration into the groundwater at the site. The following information describes the design of the bottom liner system and provides general specifications for providing and installing the associated components. This information is intended to be supplemental to the facility Permit Drawings (see Section 20) and will provide the basis for the preparation of detailed construction drawings and technical specifications associated with the construction of each waste disposal cell or area. The bottom liner system shall be constructed as follows:

o 24 inches compacted clay liner o 60-mil HDPE geomembrane liner o Geocomposite o 1 foot protective cover layer

The bottom liner system for the facility waste disposal areas will consist of two primary components. The bottom liner will consist of 24 inches of re-compacted clay that demonstrates a maximum hydraulic conductivity of 1x10-7 cm/s. The second component of the composite liner will consist of a 60-mil high density polyethylene (HDPE) liner. The HDPE liner will lie directly over the compacted clay liner. Typical sections depicting the bottom liner configuration are illustrated on the Permit Drawings provided in Section 20 of this Permit Modification Application (PMA).

2.1.1 Subgrade Surface

Prior to installation of the composite liner system, the subgrade surface will be prepared in accordance with the project specifications. At a minimum, the subgrade surface shall be free of large rocks or other irregularities and must be capable of supporting the composite liner system. The condition and suitability of the subgrade surface is to be verified by proof-rolling at a minimum.



2.1.2 Compacted Clay Liner

The compacted clay liner and synthetic components will be installed in accordance with the facility Construction Quality Assurance (CQA) Plan and the construction plans and specifications developed for the specific project. The following general guidelines shall be used in developing project specifications associated with installation of the compacted clay liner.

Clay liner shall consist of materials classified as CL and/or CH in accordance with the Unified Soil Classification System (USCS);

Clay liner shall be generally free of clods larger than four inches in diameter and shall not contain rocks larger than one inch in diameter;

Plasticity Index of the clay liner material shall be at least 10; Clay Liner shall be a minimum of 24 inches in thickness (compacted); Clay Liner shall be constructed in four lifts with each lift thickness not exceeding six

inches (compacted); Each lift shall be compacted to at least 95 percent of the soil maximum dry density based

on a standard proctor; Moisture content of the clay liner shall be maintained between 0 and 6 percent wet of the

soil optimum moisture content; Clay liner shall have a maximum hydraulic conductivity of 1 x 10-7 cm/s;

Analysis of soils at the facility was performed in conjunction with the preparation of the PMA for the proposed expansion. This information provides the basis for the design of the bottom liner system as described herein. The findings of the investigation are presented in the Hydrogeologic and Geotechnical Investigation Report.

2.1.3 60-mil HDPE Geomembrane

Geomembranes are used as the primary liners for many applications involving containment. Polyethylene is a polymeric material that exhibits both strength and elastic characteristics well suited for containment applications including sanitary landfills. Because they are the most commonly installed synthetic materials for flexible membrane liners in waste disposal facilities, testing and installation techniques are well-established. The facilitys Permit Drawings (Section 20) provide additional information on the synthetic liner systems to be used at the facility in constructing the bottom liner system. The plans include details of liner anchoring dimensions and the overall layout of the liner systems for the landfill. The Geosynthetics Research Institute (GRI) has established minimum materials standards for several geosynthetics materials including geomembranes. A copy of the GRI standards for geomembranes is included in APPENDIX A. In developing project specifications associated with construction of bottom liner systems for the Class 1 waste disposal area, the GRI standards for material properties shall be considered a minimum. During construction and operation, stresses will be exerted on the geosynthetics due to the weight of the protective cover, waste, and landfill equipment. The design of the geosynthetics



components of the bottom liner system includes provisions for perimeter anchor trenches to keep the geosynthetics in place during the construction and operation of the landfill. The anchor trenches will generally be at least 24 inches wide and at least 24 inches deep. Calculations regarding anchor trench stability are included in APPENDIX B.

2.1.4 General Installation and Operational Considerations

Materials comprising the bottom liner system may experience stresses caused by installation activities, normal operation activities, and from environmental conditions. These stresses and the methods for addressing them are presented below.

2.1.4.1 Construction Stresses

The bottom liner system components may experience a variety of stresses during construction. These include:

Pressures above and below the liner system from rocks and debris; Placement and seaming techniques; and, Pressure caused by earth-moving equipment above the liner system.

The CQA Plan outlines the various techniques to be used during liner system construction to reduce the potential of stress on the liner. In general, these include:

Cleaning and inspecting surfaces where synthetic materials will be installed; Installation of materials during appropriate conditions (temperature, wind, and rain) to

reduce problems during placement and seaming; Placement of synthetic materials considering expansion/contraction qualities of material; Use of temporary anchoring devices such as sand bags or tires to stabilize synthetic

materials; Use of low-ground pressure equipment to install materials above synthetic materials; Requirement for a minimum of one foot of material between geosynthetics and low-

ground pressure equipment, and a minimum of three feet for all other vehicles; and, Development of fill placement and spreading methodology to minimize slack

accumulation.

2.1.4.2 Climate Conditions

Stresses to the liner systems caused by climate conditions include extreme temperature ranges and excessive wind. The following design, construction, and operational techniques are to be used to minimize adverse stresses to the liner systems caused by climatic conditions:

Use HDPE materials, which can withstand a wide range of temperatures without effecting the integrity of the material;

Cover compacted clay liner systems promptly to minimize the exposure time to prevent degradation;



Install liner system within temperature range as recommended by synthetic material manufacturer;

Minimize exposure time of ultra-violet sensitive synthetic materials to sunlight; and, Anchor liner systems properly to reduce impact due to wind uplift.

2.1.4.3 Operational Stresses

During the operation of the landfill facility, stresses may be induced on the liner systems. These include pressure on the liner from landfill and waste transportation equipment as well as differential settlement stresses due to placement or settlement of waste. The following general guidelines will be followed to minimize the potential for liner stresses due to daily operations:

Waste compactors will generally traverse on waste materials only and will not be allowed on the bottom liner working surface layer; and,

A thin layer of select waste materials will form the first lift across a new cell. When spreading the waste material, a spotter will be used to observe the advancing waste face to ensure that liner materials (including the protective cover layer) are not damaged or moved. Waste transportation vehicles will use temporary haul roads constructed from on-site soils or other materials to reach the active waste face. In addition, waste placement operations will be managed to minimize pressure induced on the liner system caused by turning vehicles.

2.2 LEACHATE COLLECTION SYSTEM DESIGN

Section 22.429 of Arkansas Regulation 22 outlines requirements for the design, operation, and maintenance of leachate collection systems for Class 1 waste disposal facilities. The following information addresses the design of the leachate collection system for the facility. This information is intended to document compliance with Sections 22.429 (a) through (j) of Arkansas Regulation 22. The design of the leachate collection system associated with the facility waste disposal area includes a lateral drainage layer and a series of pipes, sumps, and pumps designed to remove leachate from the waste mass to prevent buildup of leachate head on the liner system as per Section 22.429 (a) of Arkansas Regulation 22. Once the leachate is collected, it is temporarily stored on site or diverted to a waste water treatment plant. As required by Section 22.429 (a) of Arkansas Regulation 22, the leachate collection system must be designed and operated to maintain less than 12 inches of leachate head on the liner system at any time. The HELP Model was used as the basis for the design of the leachate collection system including selection of the appropriate lateral drainage layer, minimum bottom liner grades, and spacing between leachate collection system laterals. A copy of the HELP model calculations and results associated with the bottom liner and leachate collection system are included in APPENDIX C. The results show that the design of the leachate collection system is effective in maintaining less than 12 inches of leachate head on the liner system.



The lateral drainage layer is designed to divert leachate to a series of collection laterals. The minimum slope to a collector is two percent. The collection laterals generally consist of a six inch diameter perforated HDPE pipe bedded in gravel and wrapped with a geotextile filter fabric. The leachate collection laterals are sloped at a minimum grade of one percent to a leachate collection sump. Each leachate collection sump has an individual sides-lope riser pump system.

2.2.1 Leachate Collection System Lateral Drainage Layer

According to Section 22.429 (b) of Arkansas Regulation 22, the leachate collection system shall consist of a permeable drainage layer with a minimum hydraulic conductivity of 1 x 10-3 cm/s over the top of the liner system with a system of pipes and trenches at lower portions of the disposal areas which transmit leachate to a point or location for removal. In addition, the system must include provisions for the rapid removal and storage of leachate such as storage tanks, ponds, or treatment facilities. Loading or discharge stations must be provided as necessary. The design of the leachate collection system associated with the facility waste disposal area complies with the requirements outlined in Section 22.429 (b) of Arkansas Regulation 22. According to the HELP Model results (see APPENDIX C), the configuration shown on the Permit Drawings (see Section 20) is capable of maintaining less than 12 inches of leachate head on the liner system.

2.2.2 Leachate Collection System Effectiveness And Clogging Potential

Section 22.429 (c) of Arkansas Regulation 22 states that calculations or demonstrations must be provided to show that the leachate collection system will adequately dewater the waste mass and that clogging of the system will not occur. As required by Section 22.429 (c) of Arkansas Regulation 22, the leachate collection system has been designed to minimize the potential for clogging. Calculations regarding the potential for leachate collection system clogging are included in APPENDIX D.

2.2.3 Leachate Collection Pipe Design

As per Section 22.429 (d) of Arkansas Regulation 22, leachate collection pipes to be used in the leachate collection system for the facility will be at least six inches in diameter. Perforations have been designed to minimize the potential for clogging. Specifically, perforations (3/8 inch diameter) are to be placed at 120 degree angles with a maximum spacing of 59 feet of pipe length. Leachate collection piping shall consist of HDPE piping (SDR 17) to minimize the potential for crushing or excessive deflection. Pipe crushing calculations are included in APPENDIX E. All pipes shall be sloped to drain with a minimum grade of one percent to consider future settling or consolidation of the landfill bottom.



2.2.4 Leachate Manhole/Riser Design

According to Section 22.429 (e) of Arkansas Regulation 22, leachate collection manholes or risers shall be located to prevent potential damage by landfill equipment. In addition, penetration of the liner system by leachate collection piping is discouraged. The design of the leachate collection system will include at least one side slope riser sump/pump station for each cell of the facility waste disposal areas. The side slope riser sump/pump systems are advantageous as they do not require a liner penetration. Sump areas will be located at the edge of the prepared area which will minimize the potential for damage during placement of waste fill. All sump areas will be double lined (two layers of HDPE geomembrane). In general, sump areas will be at least 40 feet by 40 feet and will be approximately two feet deep with 3:1 side-slopes into the sump with a 3:1 side-slope along the riser slope.

2.2.5 Leachate Pumping Systems

Section 22.429 (f) of Arkansas Regulation 22 outlines specific design requirements and standards for leachate collection systems. Specifically, a positive method of leachate extraction must be provided in manholes and risers in order to remove leachate in excess of the maximum allowable head level. Each developmental phase of the facility waste disposal areas will include a side-slope riser pump and control system (EPG or equivalent). Each system will be set with controls and alarm systems designed to remove leachate in excess of the maximum allowable head level. Pump sizing calculations should be performed for each cell at the time of construction. Pump controls will generally be set as follows:

Pump Off Level: 6 inches of leachate in sump Pump On Level: 36 inches of leachate in sump High Level Alarm: 60 inches of leachate in sump

2.2.6 Leachate Storage Tanks

Leachate storage tanks with secondary containment will be installed for managing the leachate that is generated at the facility. Each leachate storage tank should be designed to store the peak amount of leachate collected at any one period taking in to consideration the time needed to dispose of collected leachate.

2.2.7 Safety and Maintenance Features

As required by Section 22.429 (g) of Arkansas Regulation 22, the leachate collection system for the facility will include automatic systems with alarms and trouble lights to indicate the need for servicing, as well as automatic cut-off devices to prevent overfilling of storage tanks (or storage lagoons). The landfill operator will be able to review a digital readout associated with each side-slope riser sump/pump station to determine the level of leachate in a particular sump at a given time.



An automatic shutdown system will be installed which will kill the power to the side-slope riser pump systems if leachate levels in the tanks reach a pre-determined level.

2.2.8 Secondary Containment Outside Lined Areas

As required by Section 22.429 (h) of Arkansas Regulation 22, storage tanks and piping external to the lined area should be provided with secondary containment. As described above, the leachate storage tanks will include a secondary containment system. In addition, all new piping between the leachate storage tanks and the waste disposal areas will consist of dual contained HDPE piping.

2.2.9 Leachate Disposal

The facility will maintain accurate records regarding the volume of leachate collected and disposed. Leachate flow totalizers and/or flow meters will be installed at or for each leachate collection side-slope riser sump/pump location. In addition, the operator will monitor the accumulation of leachate head on the bottom liner system. This information will be reported to the Arkansas Department of Environmental Quality as part of the facilitys Annual Engineering Inspection Report.

2.3 FINAL COVER SYSTEM

Sections 22.1301 (a) and (b) of Arkansas Regulation 22 outline design requirements for final cover systems associated with waste disposal areas. Specifically, the final cover system must be designed to minimize infiltration of storm water into the waste mass. The following information addresses the design of the final cover system for the facility and addresses specific requirements outlined in Sections 22.1301 (a) and (b) of Arkansas Regulation 22.

2.3.1 Overview of Final Site Completion Plan

As shown on the engineering drawings included as part of this PMA, waste fill operations will proceed to a maximum landfill height of 640 fmsl. The landfill will be graded with maximum slope of twenty five percent and a minimum slope of five percent to comply with the requirements of Section 22.431 (b) of Arkansas Regulation 22.

2.3.2 Regulatory Requirements

Regulatory requirements and standards for closure of solid waste landfills are addressed in Section 22.1301 of Arkansas Regulation 22. The regulations establish standards that apply to closure of Class 1 landfills that accepted waste after October 9, 1991 and to all other Class 1, Class 3, and Class 4 landfill units in operation after May 7, 1995. The specified design is described in Section 22.1301 (a) of Arkansas Regulation 22 and includes provisions for an infiltration layer and an erosion layer. The infiltration layer must consist of at least 18 inches of earthen material that has a permeability less than or equal to the permeability of any bottom liner system or natural sub-soils present, or a permeability no greater than 1.0x10-5



cm/s, whichever is less. The erosion layer must consist of at least six inches of earthen material that is capable of sustaining native plant growth.

2.3.3 Final Cover System Components

In accordance with Section 22.1301 (a) of Arkansas Regulation 22, the final cover system for the proposed expansion of the facility consists of the following from bottom to top:

o 18 inches compacted clay barrier layer o 40-mil LLDPE geomembrane liner o Geocomposite o 1 foot vegetative cover layer

2.3.3.1 Foundation Layer

The foundation layer consists of clayey native soils that will be applied as daily and/or interim cover prior to final cover placement. The foundation layer will serve as a leveling surface and will provide support for placement of the final cover system. The foundation layer will have a minimum thickness of twelve inches. The thickness of the foundation layer may be increased as necessary to bridge over soft or loose waste areas. It should be noted, the regulations for Class 1 landfill operations require six inches of daily cover and twelve inches of intermediate cover over areas that have not received waste for 180 days. The facility may try to reclaim some of the intermediate cover, in conjunction with the placement of final cover in a particular area.

2.3.3.2 Compacted Clay Barrier Layer

This layer will consist of select native clayey soils placed in six-inch thick compacted lifts to produce a minimum total thickness of 18 inches and will be placed directly over the foundation layer. Technical specifications and standards for quality control associated with the construction of the compacted clay barrier layer are described in detail in the facility CQA Plan. At a minimum, the clay barrier layer must meet the following standards:

Minimum thickness of 18 inches; Maximum hydraulic conductivity of 1.0 x 10-7 cm/s; Material must be free of large objects including rocks; Material must have a Plasticity Index greater than 10; Material must have a fines content of 50% or greater passing a #200 sieve; Material greater than a #4 sieve must not compose more than 20 percent by weight of the

soil; and, No particles greater than 1 inch in diameter.

This information combined with the Permit Drawings (see Section 20) is intended to provide general guidelines and standards for development of detailed construction plans/specifications at the time of closure. Because materials and standards will likely change before the final cover system is actually installed, the specifications, standards, and properties should be verified and



adjusted if necessary by a licensed professional engineer in preparing detailed construction plans and technical specifications.

2.3.3.3 Geomembrane Liner

A linear low density polyethylene geomembrane liner (LLDPE) will be installed on the top of the compacted clay barrier layer. The LLDPE liner combined with the compacted clay barrier layer is designed to minimize infiltration of surface water into the waste mass. Technical specifications and standards for quality control associated with the construction of the geomembrane liner are described in detail in the facility CQA Plan (see Section 19). Detailed construction plans and technical specifications should be prepared at the time of closure of the facility. This information combined with the Permit Drawings (see Section 20) is intended to provide general guidelines and standards for development of detailed construction plans/specifications at the time of closure. Because materials and standards will likely change before the final cover system is actually installed, the specifications, standards, and properties should be verified and adjusted if necessary by a licensed professional engineer in preparing detailed construction plans and technical specifications.

2.3.3.4 Geocomposite Layer

A geocomposite will be installed directly above the geomembrane liner system. The geocomposite will act as a lateral drain to divert water that infiltrates to minimize percolation through the barrier layers and as a cushion between the vegetative cover layer and the geomembrane. A sub-surface drainage collection pipe will be installed around the perimeter of the landfill at the bottom of the final cover slopes and will direct water off the final cover system to the run-off control system.

2.3.3.5 Vegetative Cover Layer

The cover soil layer will consist of fertile topsoil. Soil additives such as fertilizer, biosolids, and/or yard waste compost will be applied and/or mixed with the top soil as needed depending on the vegetative species selected. As indicated, the vegetative cover layer will have a minimum thickness of twelve inches.

2.3.3.6 Vegetation

Selection of the appropriate vegetative species for the final cover surface is an important consideration for landfill closures. Prior to, or in conjunction with, final closure, the Howard County Cooperative Extension Service (CES) will be consulted regarding selection of appropriate plant species, seed mixtures, necessary ad-mixtures, and planting schedules. In selecting appropriate plant species, the following criteria will be considered.

Plant species must be native to the area or adaptable to local soil and climate conditions; Plants must be hardy and drought tolerant; Species must be perennial or rotational based on seasonal seed mixtures;



Plant leaf area indices must be maximized; Evapotranspiration must be maximized; Plants must be capable of protecting surface soils while controlling erosion; and, Plant species must be in aesthetic harmony with the surrounding area.

Erosion control blankets and other measures will be installed as needed in support of vegetative establishment at the site.

2.3.4 Performance Evaluation of Selected Design

In order for a final cover system to be effective, it must be capable of minimizing infiltration of surface water while minimizing erosion. The final cover system must also be stable under static and seismic loading conditions. In selecting the design of the final cover system for the closure of the landfill, these and other criteria were considered. The following information summarizes the various performance criteria and associated results.

2.3.4.1 Infiltration

Final cover systems for solid waste landfills must be effective in minimizing infiltration of surface water into the waste mass. The hydraulic performance of the selected design for the landfill was evaluated using the computer program HELP (see APPENDIX C). The results of the HELP analysis show that the selected design for closure of the facility will minimize surface water infiltration. Landfill leakage associated with the design is considered negligible for a landfill of this size.

2.3.4.2 Stability

The stability of the landfill final configuration was evaluated using the computer program Galena Slope Stability Analysis System (see APPENDIX F). The analysis of the landfill final configuration demonstrates that the landfill is stable under static and dynamic loading conditions.

2.3.4.3 Erosion Control

The final cover system design includes provisions to control erosion particularly on the side slopes (4:1). Specifically, mid-slope drainage berms (with provisions for let down structures) are to be installed. In addition, the vegetative cover will be selected based on its ability to minimize erosion of surface soils. If erosion is experienced, corrective measures should be employed such as:

Regrading and reseeding; Installation of erosion control matting; and, Installation of hay bales and silt fence.



2.4 SURFACE WATER CONTROL

Section 22.418 of Arkansas Regulation 22 outlines specific requirements for run-on and run-off control systems associated with Class 1 waste disposal areas. Owners and operators of landfills are required to design, construct, and maintain run-on and run-off control systems that include the following:

1. A run-on control system to prevent the flow onto the active portion of the landfill or waste processing area during the peak discharge from a 24-hour, 25-year storm; 2. A run-off control system from the active portion of the landfill to collect and control at least the water volume resulting from a 24-hour, 25-year storm.

The storm water management plan developed for the landfill includes a series of berms, ditches, and drainage conveyances to direct storm water away from and around the active disposal area. Storm water diversion is necessary and desirable to minimize contact with waste which will limit the potential for leachate production. Each active waste cell will be constructed with a perimeter diversion berm to assist in separating leachate and storm water. The surface of the landfill will be shaped and contoured to promote proper drainage. A series of intermediate and internal ditches will be necessary to divert storm water run-off from the landfill to the perimeter ditches. The final cover system will also include a series of mid-slope drainage conveyances designed to control drainage off the landfill surface while minimizing erosion. All surface water run-off will be directed to the storm water sediment pond. The storm water management plan was analyzed through a comprehensive storm water analysis of the facility. Detailed design calculations are included in APPENDIX G.

2.5 EARTHWORK

As referenced in Section 22.430 of Arkansas Regulation 22, solid waste disposal facility permit applications and permit modification applications should include a tabulation of the excavation and material quantities required to construct and operate the facility as designed. The following information describes the amount of soil needed for construction and operation of the facility. This information provides the basis for soil budgeting and planning as described herein.

2.5.1 Landfill Construction Soil Needs

Based on the design of the waste disposal areas as presented in the facility Permit Drawings (see Section 20), approximately 60,000 cubic yards of clay liner material will be required to construct the bottom liner system associated with all waste disposal areas currently unprepared as of the date of this PMA. An additional 140,000 cubic yards of clay material will be required to construct the compacted clay barrier layer in the final cover system. Approximately 95,000 cubic yards of material is required to construct the twelve inch thick vegetative cover layer. Approximately 30,000 cubic yards is required to construct the protective cover layer of the



bottom liner system. Based on this information, the soil needed to construct the bottom liner and final cover system is as follows: Clay liner/barrier layer material: 200,000 cubic yards Protective Cover Layers: 30,000 cubic yards Vegetation support soil: 95,000 cubic yards Unless otherwise noted, all quantities shown are in "bank yards" as opposed to "truck yards". A factor of 1.5 should be used in converting "bank yards" to "truck yards".

2.5.2 Landfill Operational Soil Needs

The approximate operational soil use rate is 22,000 cubic yards per year. This material is generally used for daily/interim cover and construction of intermediate roads within the waste disposal areas.

2.5.3 Available Soil Material

The total quantity of soil available from the excavation of the proposed waste disposal areas at the facility was calculated to be approximately 560,000 cubic yards to the bottom of the clay liner elevations. There will be some clay material available from that excavation quantity. However, there are 348 acres within the facility boundary and other areas are expected to be utilized as clay borrow areas. Within the facility there is ample material available for landfill construction.

2.5.4 Soil Balance

As described above, approximately 200,000 cubic yards of clay liner/clay barrier layer material are needed to construct the bottom liner and final cover systems. An additional 95,000 cubic yards of earthen material is needed to construct the vegetation support layer. Approximately 30,000 cubic yards of material are needed to construct the protective cover layer of the bottom liner system. Approximately 22,000 cubic yards are needed for daily/interim cover and roads during the operational life of the facility. Approximately 457,000 cubic yards of material are available on site associated with planned excavation areas (future waste cells). The excavated material will supply adequate quantities for the vegetative support layer and the daily interim cover. There will also be some amount of clay that will be excavated and will be stockpiled for use as clay liner/clay barrier layer. Additional clay will be excavated from a 16 acre borrow area located on a portion of the 43.5 acres of property that was purchased for the proposed expansion. The material for the protective cover layer will be hauled in from an off-site source as it has been for previous cells constructed at the site. Therefore, the USARSWMD does not anticipate a clay soil deficit for the construction of the bottom liner and final cover systems.



2.6 WASTE CAPACITY AND SITE LIFE

Section 22.303(c)(8) of Arkansas Regulation 22 requires that information regarding landfill capacity and service life be included in applications for new permits and permit modifications associated with waste disposal facilities. The following information is intended to document compliance with Section 22.303(c)(8) of Arkansas Regulation 22. As of the most recent survey for the site (October 2017), approximately 541,000 cubic yards of void space were remaining. Based on the 2016 landfill utilization rate, the existing permitted capacity will be exhausted by approximately the middle of 2021. The available airspace for waste disposal associated with the proposed expansion was calculated with a three-dimensional computer model. The results of the calculations are presented in APPENDIX H. The model calculated the airspace between the proposed bottom grading plan (top of protective cover) and the top of the proposed intermediate final cover plan. The total airspace (waste and interim cover) associated with the proposed expansion is approximately 2,325,048 cubic yards. This will bring the total landfill permitted capacity to approximately 5,664,873 cubic yards. The current disposal rate at the landfill is approximately 148,000 cubic yards per year. If this disposal rate continues, the estimated service life of the landfill while considering the modified capacity is approximately 19.4 years from the most recent survey date.


Civil Engineering Associates, LLC January 2018

APPENDIX A GRI GEOMEMBRANE STANDARDS

GM13 - 1 of 11 Revision 14: 1/6/16

Revision 14: January 6, 2016 Revision schedule on pg. 11

GRI - GM13 Standard Specification* Standard Specification for

Test Methods, Test Properties and Testing Frequency for High Density Polyethylene (HDPE) Smooth and Textured Geomembranes SM

This specification was developed by the Geosynthetic Research Institute (GRI), with the cooperation of the member organizations for general use by the public. It is completely optional in this regard and can be superseded by other existing or new specifications on the subject matter in whole or in part. Neither GRI, the Geosynthetic Institute, nor any of its related institutes, warrant or indemnifies any materials produced according to this specification either at this time or in the future. 1. Scope

1.1 This specification covers high density polyethylene (HDPE) geomembranes with a formulated sheet density of 0.940 g/ml, or higher, in the thickness range of 0.75 mm (30 mils) to 3.0 mm (120 mils). Both smooth and textured geomembrane surfaces are included.

1.2 This specification sets forth a set of minimum, physical, mechanical and chemical

properties that must be met, or exceeded by the geomembrane being manufactured. In a few cases a range is specified.

1.3 In the context of quality systems and management, this specification represents

manufacturing quality control (MQC).

Note 1: Manufacturing quality control represents those actions taken by a manufacturer to ensure that the product represents the stated objective and properties set forth in this specification.

1.4 This standard specification is intended to ensure good quality and performance of

HDPE geomembranes in general applications, but is possibly not adequate for the complete specification in a specific situation. Additional tests, or more restrictive

*This GRI standard specification is developed by the Geosynthetic Research Institute through consultation and review by the member organizations. This specification will be reviewed at least every 2-years, or on an as-required basis. In this regard it is subject to change at any time. The most recent revision date is the effective version and it is kept current on the Institutes Website .

Copyright 2017 Geosynthetic Institute - All Rights Reserved

Geosynthetic Institute

475 Kedron Avenue Folsom, PA 19033-1208 USA

TEL (610) 522-8440 FAX (610) 522-8441

GSI

GRI GII

GAI

GEI

GCI

GM13 - 2 of 11 Revision 14: 1/6/16

values for test indicated, may be necessary under conditions of a particular application.

Note 2: For information on installation techniques, users of this standard are

referred to the geosynthetics literature, which is abundant on the subject.

2. Referenced Documents

2.1 ASTM Standards D 792 Specific Gravity (Relative Density) and Density of Plastics by

Displacement D 1004 Test Method for Initial Tear Resistance of Plastics Film and Sheeting D 1238 Test Method for Flow Rates of Thermoplastics by Extrusion Plastometer D 1505 Test Method for Density of Plastics by the Density-Gradient Technique D 1603 Test Method for Carbon Black in Olefin Plastics D 3895 Test Method for Oxidative Induction Time of Polyolefins by Thermal

Analysis D 4218 Test Method for Determination of Carbon Black Content in

Polyethylene Compounds by the Muffle-Furnace Technique D 4833 Test Method for Index Puncture Resistance of Geotextiles,

Geomembranes and Related Products D 5199 Test Method for Measuring Nominal Thickness of Geotextiles and

Geomembranes D 5397 Procedure to Perform a Single Point Notched Constant Tensile Load

(SP-NCTL) Test: Appendix D 5596 Test Method for Microscopic Evaluation of the Dispersion of Carbon

Black in Polyolefin Geosynthetics D 5721 Practice for Air-Oven Aging of Polyolefin Geomembranes D 5885 Test method for Oxidative Induction Time of Polyolefin Geosynthetics

by High Pressure Differential Scanning Calorimetry D 5994 Test Method for Measuring the Core Thickness of Textured

Geomembranes D 6370 Standard Test Method for Rubber-Compositional Analysis by

Thermogravimetry (TGA) D 6693 Test Method for Determining Tensile Properties of Nonreinforced

Polyethylene and Nonreinforced Flexible Polypropylene Geomembranes D 7238 Test Method for Effect of Exposure of Unreinforced Polyolefin

Geomembrane Using Fluorescent UV Condensation Apparatus D 7466 Test Method for Measuring the Asperity Height of Textured

Geomembranes

2.2 GRI Standards

GM10 Specification for the Stress Crack Resistance of Geomembrane Sheet

GM13 - 3 of 11 Revision 14: 1/6/16

2.3 U. S. Environmental Protection Agency Technical Guidance Document "Quality

Control Assurance and Quality Control for Waste Containment Facilities," EPA/600/R-93/182, September 1993, 305 pgs.

3. Definitions

Manufacturing Quality Control (MQC) - A planned system of inspections that is used to directly monitor and control the manufacture of a material which is factory originated. MQC is normally performed by the manufacturer of geosynthetic materials and is necessary to ensure minimum (or maximum) specified values in the manufactured product. MQC refers to measures taken by the manufacturer to determine compliance with the requirements for materials and workmanship as stated in certification documents and contract specifications. ref. EPA/600/R-93/182

Manufacturing Quality Assurance (MQA) - A planned system of activities that provides assurance that the materials were constructed as specified in the certification documents and contract specifications. MQA includes manufacturing facility inspections, verifications, audits and evaluation of the raw materials (resins and additives) and geosynthetic products to assess the quality of the manufactured materials. MQA refers to measures taken by the MQA organization to determine if the manufacturer is in compliance with the product certification and contract specifications for the project. ref. EPA/600/R-93/182

Formulation, n - The mixture of a unique combination of ingredients identified by type, properties and quantity. For HDPE polyethylene geomembranes, a formulation is defined as the exact percentages and types of resin(s), additives and carbon black.

4. Material Classification and Formulation

4.1 This specification covers high density polyethylene geomembranes with a formulated sheet density of 0.940 g/ml, or higher. Density can be measured by ASTM D1505 or ASTM D792. If the latter, Method B is recommended.

4.2 The polyethylene resin from which the geomembrane is made will generally be in

the density range of 0.932 g/ml or higher, and have a melt index value per ASTM D1238 of less than 1.0 g/10 min.

4.3 The resin shall be virgin material with no more than 10% rework. If rework is

used, it must be a similar HDPE as the parent material. 4.4 No post consumer resin (PCR) of any type shall be added to the formulation.

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5. Physical, Mechanical and Chemical Property Requirements

5.1 The geomembrane shall conform to the test property requirements prescribed in Tables 1 and 2. Table 1 is for smooth HDPE geomembranes and Table 2 is for single and double sided textured HDPE geomembranes. Each of the tables are given in English and SI (metric) units. The conversion from English to SI (metric) is soft.

Note 3: The tensile strength properties in this specification were originally

based on ASTM D 638 which uses a laboratory testing temperature of 23C 2C. Since ASTM Committee D35 on Geosynthetics adopted ASTM D 6693 (in place of D 638), this GRI Specification followed accordingly. The difference is that D 6693 uses a testing temperature of 21C 2C. The numeric values of strength and elongation were not changed in this specification. If a dispute arises in this regard, the original temperature of 23C 2C should be utilized for testing purposes.

Note 4: There are several tests often included in other HDPE specifications

which are omitted from this standard because they are outdated, irrelevant or generate information that is not necessary to evaluate on a routine MQC basis. The following tests have been purposely omitted:

Volatile Loss Water Absorption Dimensional Stability Ozone Resistance Coeff. of Linear Expansion Modulus of Elasticity Resistance to Soil Burial Hydrostatic Resistance Low Temperature Impact Tensile Impact ESCR Test (D 1693) Field Seam Strength Wide Width Tensile Multi-Axial Burst Water Vapor Transmission Various Toxicity Tests

Note 5: There are several tests which are included in this standard (that are

not customarily required in other HDPE specifications) because they are relevant and important in the context of current manufacturing processes. The following tests have been purposely added:

Oxidative Induction Time Oven Aging Ultraviolet Resistance Asperity Height of Textured Sheet (see Note 6)

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Note 6: The minimum average value of asperity height does not represent an expected value of interface shear strength. Shear strength associated with geomembranes is both site-specific and product-specific and should be determined by direct shear testing using ASTM D5321/ASTM D6243 as prescribed. This testing should be included in the particular sites CQA conformance testing protocol for the geosynthetic materials involved, or formally waived by the Design Engineer, with concurrence from the Owner prior to the deployment of the geosynthetic materials.

Note 7: There are other tests in this standard, focused on a particular

property, which are updated to current standards. The following are in this category:

Thickness of Textured Sheet Puncture Resistance Stress Crack Resistance Carbon Black Dispersion (In the viewing and subsequent

quantitative interpretation of ASTM D 5596 only near spherical agglomerates shall be included in the assessment).

5.2 The values listed in the tables of this specification are to be interpreted according

to the designated test method. In this respect they are neither minimum average roll values (MARV) nor maximum average roll values (MaxARV).

5.3 The properties of the HDPE geomembrane shall be tested at the minimum

frequencies shown in Tables 1 and 2. If the specific manufacturer's quality control guide is more stringent and is certified accordingly, it must be followed in like manner.

Note 8: This specification is focused on manufacturing quality control

(MQC). Conformance testing and manufacturing quality assurance (MQA) testing are at the discretion of the purchaser and/or quality assurance engineer, respectively.

6. Workmanship and Appearance

6.1 Smooth geomembrane shall have good appearance qualities. It shall be free from such defects that would affect the specified properties of the geomembrane.

6.2 Textured geomembrane shall generally have uniform texturing appearance. It

shall be free from agglomerated texturing material and such defects that would affect the specified properties of the geomembrane.

6.3 General manufacturing procedures shall be performed in accordance with the

manufacturer's internal quality control guide and/or documents.

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7. MQC Sampling

7.1 Sampling shall be in accordance with the specific test methods listed in Tables 1 and 2. If no sampling protocol is stipulated in the particular test method, then test specimens shall be taken evenly spaced across the entire roll width.

7.2 The number of tests shall be in accordance with the appropriate test methods

listed in Tables 1 and 2. 7.3 The average of the test results should be calculated per the particular standard

cited and compared to the minimum value listed in these tables, hence the values listed are the minimum average values and are designated as "min. ave."

8. MQC Retest and Rejection

8.1 If the results of any test do not conform to the requirements of this specification, retesting to determine conformance or rejection should be done in accordance with the manufacturing protocol as set forth in the manufacturer's quality manual.

9. Packaging and Marketing

9.1 The geomembrane shall be rolled onto a substantial core or core segments and held firm by dedicated straps/slings, or other suitable means. The rolls must be adequate for safe transportation to the point of delivery, unless otherwise specified in the contract or order.

10. Certification

10.1 Upon request of the purchaser in the contract or order, a manufacturer's certification that the material was manufactured and tested in accordance with this specification, together with a report of the test results, shall be furnished at the time of shipment.

GM13 - 7 of 11 Revision 14: 1/6/16

Table 1(a) High Density Polyethylene (HDPE) Geomembrane -Smooth

Properties Test Test Value Testing Frequency

Method 30 mils 40 mils 50 mils 60 mils 80 mils 100 mils 120 mils (minimum) Thickness (min. ave.) D5199 nom. nom. nom. nom. nom. nom. nom. Per roll

lowest individual of 10 values -10% -10% -10% -10% -10% -10% -10% Formulated Density mg/l (min.) D 1505/D 792 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 200,000 lb Tensile Properties (1) (min. ave.)

yield strength break strength yield elongation break elongation

D 6693 Type IV

63 lb/in.

114 lb/in. 12%

700%

84 lb/in.

152 lb/in. 12%

700%

105 lb/in. 190 lb/in.

12% 700%

126 lb/in. 228 lb/in.

12% 700%

168 lb/in. 304 lb/in.

12% 700%

210 lb/in. 380 lb/in.

12% 700%

252 lb/in. 456 lb/in.

12% 700%

20,000 lb

Tear Resistance (min. ave.) D 1004 21 lb 28 lb 35 lb 42 lb 56 lb 70 lb 84 lb 45,000 lb Puncture Resistance (min. ave.) D 4833 54 lb 72 lb 90 lb 108 lb 144 lb 180 lb 216 lb 45,000 lb Stress Crack Resistance (2) D5397

(App.) 500 hr. 500 hr. 500 hr. 500 hr. 500 hr. 500 hr. 500 hr. per GRI-GM10

Carbon Black Content (range) D 4218 (3) 2.0-3.0% 2.0-3.0% 2.0-3.0% 2.0-3.0% 2.0-3.0% 2.0-3.0% 2.0-3.0% 20,000 lb Carbon Black Dispersion D 5596 note (4) note (4) note (4) note (4) note (4) note (4) note (4) 45,000 lb Oxidative Induction Time (OIT) (min. ave.) (5) (a) Standard OIT or (b) High Pressure OIT

D 3895

D 5885

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

200,000 lb

Oven Aging at 85C (5), (6) D 5721 (a) Standard OIT (min. ave.) - % retained after 90 days or (b) High Pressure OIT (min. ave.) - % retained after 90 days

D 3895

D 5885

55%

80%

55%

80%

55%

80%

55%

80%

55%

80%

55%

80%

55%

80%

per each formulation

UV Resistance (7) D 7238 (a) Standard OIT (min. ave.) or (b) High Pressure OIT (min. ave.) - % retained after 1600 hrs (9)

D 3895

D 5885

N.R. (8)

50%

N.R. (8)

50%

N.R. (8)

50%

N.R. (8)

50%

N.R. (8)

50%

N.R. (8)

50%

N.R. (8)

50%


(1) Machine direction (MD) and cross machine direction (XMD) average values should be on the basis of 5 test specimens each direction. Yield elongation is calculated using a gage length of 1.3 inches Break elongation is calculated using a gage length of 2.0 in. (2) The yield stress used to calculate the applied load for the SP-NCTL test should be the manufacturers mean value via MQC testing. (3) Other methods such as D 1603 (tube furnace) or D 6370 (TGA) are acceptable if an appropriate correlation to D 4218 (muffle furnace) can be established. (4) Carbon black dispersion (only near spherical agglomerates) for 10 different views: 9 in Categories 1 or 2 and 1 in Category 3 (5) The manufacturer has the option to select either one of the OIT methods listed to evaluate the antioxidant content in the geomembrane. (6) It is also recommended to evaluate samples at 30 and 60 days to compare with the 90 day response. (7) The condition of the test should be 20 hr. UV cycle at 75C followed by 4 hr. condensation at 60C. (8) Not recommended since the high temperature of the Std-OIT test produces an unrealistic result for some of the antioxidants in the UV exposed samples. (9) UV resistance is based on percent retained value regardless of the original HP-OIT value.

ENGLISH UNITS

GM13 - 8 of 11 Revision 14: 1/6/16

Table 1(b) High Density Polyethylene (HPDE) Geomembrane - Smooth

Properties Test Test Value Testing Frequency

Method 0.75 mm 1.00 mm 1.25 mm 1.50 mm 2.00 mm 2.50 mm 3.00 mm (minimum) Thickness - mils (min. ave.) D5199 nom. (mil) nom. (mil) nom. (mil) nom. (mil) nom. (mil) nom. (mil) nom. (mil) per roll

lowest individual of 10 values -10% -10% -10% -10% -10% -10% -10% Formulated Density (min.) D 1505/D 792 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 90,000 kg Tensile Properties (1) (min. ave.)


D 6693 Type IV

11 kN/m 20 kN/m

12% 700%

15 kN/m 27 kN/m

12% 700%

18 kN/m 33 kN/m

12% 700%

22 kN/m 40 kN/m

12% 700%

29 kN/m 53 kN/m

12% 700%

37 kN/m 67 kN/m

12% 700%

44 kN/m 80 kN/m

12% 700%

9,000 kg

Tear Resistance (min. ave.) D 1004 93 N 125 N 156 N 187 N 249 N 311 N 374 N 20,000 kg Puncture Resistance (min. ave.) D 4833 240 N 320 N 400 N 480 N 640 N 800 N 960 N 20,000 kg Stress Crack Resistance (2) D 5397 500 hr. 500 hr. 500 hr. 500 hr. 500 hr. 500 hr. 500 hr. per GRI GM-10 (App.) Carbon Black Content - % D 4218 (3) 2.0-3.0% 2.0-3.0% 2.0-3.0% 2.0-3.0% 2.0-3.0% 2.0-3.0% 2.0-3.0% 9,000 kg Carbon Black Dispersion D 5596 note (4) note (4) note (4) note (4) note (4) note (4) note (4) 20,000 kg Oxidative Induction Time (OIT) (min. ave.) (5) (a) Standard OIT or (b) High Pressure OIT

D 3895

D 5885

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

90,000 kg

Oven Aging at 85C (5), (6) D 5721 (a) Standard OIT (min. ave.) - % retained after 90 days or (b) High Pressure OIT (min. ave.) - % retained after 90 days

D 3895

D 5885

55%

80%

55%

80%

55%

80%

55%

80%

55%

80%

55%

80%

55%

80%


UV Resistance (7) D 7238 (a) Standard OIT (min. ave.) or (b) High Pressure OIT (min. ave.) - % retained after 1600 hrs (9)

D 3895

D 5885

N. R. (8)

50%

N.R. (8)

50%

N.R. (8)

50%

N.R. (8)

50%

N.R. (8)

50%

N.R. (8)

50%

N.R. (8)

50%


(1) Machine direction (MD) and cross machine direction (XMD) average values should be on the basis of 5 test specimens each direction

Yield elongation is calculated using a gage length of 33 mm Break elongation is calculated using a gage length of 50 mm

(2) The yield stress used to calculate the applied load for the SP-NCTL test should be the manufacturers mean value via MQC testing. (3) Other methods such as D 1603 (tube furnace) or D 6370 (TGA) are acceptable if an appropriate correlation to D 4218 (muffle furnace) can be established. (4) Carbon black dispersion (only near spherical agglomerates) for 10 different views:

9 in Categories 1 or 2 and 1 in Category 3 (5) The manufacturer has the option to select either one of the OIT methods listed to evaluate the antioxidant content in the geomembrane. (6) It is also recommended to evaluate samples at 30 and 60 days to compare with the 90 day response. (7) The condition of the test should be 20 hr. UV cycle at 75C followed by 4 hr. condensation at 60C. (8) Not recommended since the high temperature of the Std-OIT test produces an unrealistic result for some of the antioxidants in the UV exposed samples. (9) UV resistance is based on percent retained value regardless of the original HP-OIT value.

SI (METRIC) UNITS

GM13 - 9 of 11 Revision 14: 1/6/16

Table 2(a) High Density Polyethylene (HDPE) Geomembrane - Textured

Properties Test

Method Test Value Testing

Frequency 30 mils 40 mils 50 mils 60 mils 80 mils 100 mils 120 mils (minimum) Thickness mils (min. ave.)

lowest individual for 8 out of 10 values lowest individual for any of the 10 values

D 5994 nom. (-5%) -10% -15%

nom. (-5%) -10% -15%

nom. (-5%) -10% -15%

nom. (-5%) -10% -15%

nom. (-5%) -10% -15%

nom. (-5%) -10% -15%

nom. (-5%) -10% -15%

per roll

Asperity Height mils (min. ave.) D 7466 16 mil 16 mil 16 mil 16 mil 16 mil 16 mil 16 mil every 2nd roll (1) Formulated Density (min. ave.) D 1505/D 792 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 200,000 lb Tensile Properties (min. ave.) (2)


D 6693 Type IV

63 lb/in. 45 lb/in.

12% 100%

84 lb/in. 60 lb/in.

12% 100%

105 lb/in. 75 lb/in.

12% 100%

126 lb/in. 90 lb/in.

12% 100%

168 lb/in. 120 lb/in.

12% 100%

210 lb/in. 150 lb/in.

12% 100%

252 lb/in. 180 lb/in.

12% 100%

20,000 lb

Tear Resistance (min. ave.) D 1004 21 lb 28 lb 35 lb 42 lb 56 lb 70 lb 84 lb 45,000 lb Puncture Resistance (min. ave.) D 4833 45 lb 60 lb 75 lb 90 lb 120 lb 150 lb 180 lb 45,000 lb Stress Crack Resistance (3) D 5397

(App.) 500 hr. 500 hr. 500 hr. 500 hr. 500 hr. 500 hr. 500 hr. per GRI GM10

Carbon Black Content (range) D 4218 (4) 2.0-3.0 % 2.0-3.0 % 2.0-3.0 % 2.0-3.0 % 2.0-3.0 % 2.0-3.0 % 2.0-3.0 % 20,000 lb Carbon Black Dispersion D 5596 note (5) note (5) note (5) note (5) note (5) note (5) note (5) 45,000 lb Oxidative Induction Time (OIT) (min. ave.) (6) (a) Standard OIT

or (b) High Pressure OIT

D 3895

D 5885

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

200,000 lb

Oven Aging at 85C (6), (7) D 5721 (a) Standard OIT (min. ave.) - % retained after 90 days

or (b) High Pressure OIT (min. ave.) - % retained after 90 days

D 3895

D 5885

55%

80%

55%

80%

55%

80%

55%

80%

55%

80%

55%

80%

55%

80%

per each

formulation

UV Resistance (8) D 7238 (a) Standard OIT (min. ave.)

or

(b) High Pressure OIT (min. ave.) - % retained after 1600 hrs (10)

D 3895

D 5885

N.R. (9)

50%

N.R. (9)

50%

N.R. (9)

50%

N.R. (9)

50%

N.R. (9)

50%

N.R. (9)

50%

N.R. (9)

50%

per each

formulation

(1) Alternate the measurement side for double sided textured sheet (2) Machine direction (MD) and cross machine direction (XMD) average values should be on the basis of 5 test specimens each direction.

Yield elongation is calculated using a gage length of 1.3 inches Break elongation is calculated using a gage length of 2.0 inches

(3) SP-NCTL per ASTM D5397 Appendix, is not appropriate for testing geomembranes with textured or irregular rough surfaces. Test should be conducted on smooth edges of textured rolls or on smooth sheets made from the same formulation as being used for the textured sheet materials. The yield stress used to calculate the applied load for the SP-NCTL test should be the manufacturers mean value via MQC testing.

(4) Other methods such as D 1603 (tube furnace) or D 6370 (TGA) are acceptable if an appropriate correlation to D 4218 (muffle furnace) can be established. (5) Carbon black dispersion (only near spherical agglomerates) for 10 different views: 9 in Categories 1 or 2 and 1 in Category 3 (6) The manufacturer has the option to select either one of the OIT methods listed to evaluate the antioxidant content in the geomembrane. (7) It is also recommended to evaluate samples at 30 and 60 days to compare with the 90 day response. (8) The condition of the test should be 20 hr. UV cycle at 75C followed by 4 hr. condensation at 60C. (9) Not recommended since the high temperature of the Std-OIT test produces an unrealistic result for some of the antioxidants in the UV exposed samples. (10) UV resistance is based on percent retained value regardless of the original HP-OIT value.

ENGLISH UNITS

GM13 - 10 of 11 Revision 14: 1/6/16

Table 2(b) High Density Polyethylene (HDPE) Geomembrane - Textured

Properties Test Method

Test Value Testing Frequency

0.75 mm 1.00 mm 1.25 mm 1.50 mm 2.00 mm 2.50 mm 3.00 mm (minimum) Thickness mils (min. ave.)

lowest individual for 8 out of 10 values lowest individual for any of the 10 values

D 5994 nom. (-5%) -10% -15%

nom. (-5%) -10% -15%

nom. (-5%) -10% -15%

nom. (-5%) -10% -15%

nom. (-5%) -10% -15%

nom. (-5%) -10% -15%

nom. (-5%) -10% -15%

per roll

Asperity Height mils (min. ave.) D 7466 0.40 mm 0.40 mm 0.40 mm 0.40 mm 0.40 mm 0.40 mm 0.40 mm every 2nd roll (1) Formulated Density (min. ave.) D 1505/D 792 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 0.940 g/cc 90,000 kg Tensile Properties (min. ave.) (2)


D 6693 Type IV

11 kN/m 8 kN/m

12% 100%

15 kN/m 10 kN/m

12% 100%

18 kN/m 13 kN/m

12% 100%

22 kN/m 16 kN/m

12% 100%

29 kN/m 21 kN/m

12% 100%

37 kN/m 26 kN/m

12% 100%

44 kN/m 32 kN/m

12% 100%

9,000 kg

Tear Resistance (min. ave.) D 1004 93 N 125 N 156 N 187 N 249 N 311 N 374 N 20,000 kg Puncture Resistance (min. ave.) D 4833 200N 267 N 333 N 400 N 534 N 667 N 800 N 20,000 kg Stress Crack Resistance (3) D 5397

(App.) 500 hr. 500 hr. 500 hr. 500 hr. 500 hr. 500 hr. 500 hr. per GRI GM10

Carbon Black Content (range) D 4218 (4) 2.0-3.0 % 2.0-3.0 % 2.0-3.0 % 2.0-3.0 % 2.0-3.0 % 2.0-3.0 % 2.0-3.0 % 9,000 kg Carbon Black Dispersion D 5596 note (5) note (5) note (5) note (5) note (5) note (5) note (5) 20,000 kg Oxidative Induction Time (OIT) (min. ave.) (6) (a) Standard OIT or

(b) High Pressure OIT

D 3895

D 5885

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

100 min.

400 min.

90,000 kg

Oven Aging at 85C (6), (7) D 5721 (a) Standard OIT (min. ave.) - % retained after 90 days or

(b) High Pressure OIT (min. ave.) - % retained after 90 days

D 3895

D 5885

55%

80%

55%

80%

55%

80%

55%

80%

55%

80%

55%

80%

55%

80%


UV Resistance (8) D 7238 (a) Standard OIT (min. ave.)

or (b) High Pressure OIT (min. ave.) - % retained after 1600 hrs (10)

D 3895

D 5885

N.R. (9)

50%

N.R. (9)

50%

N.R. (9)

50%

N.R. (9)

50%

N.R. (9)

50%

N.R. (9)

50%

N.R. (9)

50%

per each

formulation

(1) Alternate the measurement side for double sided textured sheet (2) Machine direction (MD) and cross machine direction (XMD) average values should be on the basis of 5 test specimens each direction.

Yield elongation is calculated using a gage length of 33 mm Break elongation is calculated using a gage length of 50 mm

(3) The SP-NCTL test is not appropriate for testing geomembranes with textured or irregular rough surfaces. Test should be conducted on smooth edges of textured rolls or on smooth sheets made from the same formulation as being used for the textured sheet materials.

The yield stress used to calculate the applied load for the SP-NCTL test should be the manufacturers mean value via MQC testing. (4) Other methods such as D 1603 (tube furnace) or D 6370 (TGA) are acceptable if an appropriate correlation to D 4218 (muffle furnace) can be established. (5) Carbon black dispersion (only near spherical agglomerates) for 10 different views:

9 in Categories 1 or 2 and 1 in Category 3 (6) The manufacturer has the option to select either one of the OIT methods listed to evaluate the antioxidant content in the geomembrane. (7) It is also recommended to evaluate samples at 30 and 60 days to compare with the 90 day response. (8) The condition of the test should be 20 hr. UV cycle at 75C followed by 4 hr. condensation at 60C. (9) Not recommended since the high temperature of the Std-OIT test produces an unrealistic result for some of the antioxidants in the UV exposed samples. (10) UV resistance is based on percent retained value regardless of the original HP-OIT value.

SI (METRIC UNITS)

GM13 - 11 of 11 Revision 14: 1/6/16

Adoption and Revision Schedule for

HDPE Specification per GRI-GM13

Test Methods, Test Properties, Testing Frequency for High Density Polyethylene (HDPE) Smooth and Textured Geomembranes

Adopted: June 17, 1997 Revision 1: November 20, 1998; changed CB dispersion from allowing 2 views to be in Category 3 to requiring all 10 views to be in Category 1 or 2. Also reduced UV percent retained from 60% to 50%. Revision 2: April 29, 1999: added to Note 5 after the listing of Carbon Black Dispersion the following: (In the viewing and subsequent quantitative interpretation of ASTM D5596 only near spherical agglomerates shall be included in the assessment) and to Note (4) in the property tables.

Revision 3: June 28, 2000: added a new Section 5.2 that the numeric table values are neither MARV or MaxARV. They are to be interpreted per the the designated test method. Revision 4: December 13, 2000: added one Category 3 is allowed for carbon black dispersion. Also, unified terminology to strength and elongation. Revision 5: May 15, 2003: Increased minimum acceptable stress crack resistance time from 200 hrs to 300 hrs. Revision 6: June 23, 2003: Adopted ASTM D 6693, in place of ASTM D 638, for tensile strength testing. Also, added Note 2. Revision 7: February 20, 2006: Added Note 6 on Asperity Height clarification with respect to shear strength. Revision 8: Removed recommended warranty from specification. Revision 9: June 1, 2009: Replaced GRI-GM12 test for asperity height of textured geomembranes with ASTM D 7466. Revision 10 April 11, 2011: Added alternative carbon black content test methods Revision 11 December 13, 2012: Replaced GRI-GM11 with the equivalent ASTM D 7238. Revision 12 November 14, 2014: Increased minimum acceptable stress crack resistance time from 300 to 500 hours. Also, increased asperity height of textured sheet from 10 to 16 mils (0.25 to 0.40 mm). Revision 13 November 4, 2015: Removed Footnote (1) on asperity height from tables. Revision 14 January 6, 2016: Removed Trouser Tear from Note 5.


Civil Engineering Associates, LLC January 2018

APPENDIX B ANCHOR TRENCH CALCULATIONS

CALCULATION SUMMARY SHEET

PROJECT USARSWMD Class 1 Landfill Permit Modification Application

PROJECT SW-10-01

CALCULATION TITLE Anchor Trench Calculations

CALCULATION NO. 1

ORIGINATED BY Lance Powell, P.E.

DATE 12/05/2017

CHECKED BY Jason MacDonald, P.E.

DATE 12/05/2017

SUBJECT:

Verification of the anchor trench dimensions and run-out length for the geosynthetic installations corresponding to the landfill area.

DESCRIPTION OF PROBLEM:

Anchor trenches are required at the top of the bottom liner slopes to hold all the geosynthetic materials in place. However, pullout of the geosynthetics from the anchor trench is preferable to failure in the geosynthetic material. Thus the design anchor trench should provide anchor resistance slightly less than that which would cause tensile rupture and seperation of the geosynthetic.

SOURCES OF DATA:

Designing with Geosynthetics; Fifth Edition, Robert M. Koerner Hydogeologic and Geotechnical Investigation Report, SCS Engineers (October 2017)Permit Design Drawings, USARSWMD Class 1 Landfill (November 2017) GSE Environmental Textured Membrane Product Data Sheet

INTENDED USE: PRELIMINARY CALC.

FINAL CALC.

SUPERCEDES CALC NO.____________

OTHER___________________________

REV NO

DESCRIPTION BY DATE CHK DATE

x

Anchor Trench Design

List of Variables:

Ye

he

be

=unit weight of cover soil

=depth of cover soil

=interface friction angle between geomembrane and underlying soil

Fat

Fror

=friction force at anchor trench

=Total frictional forces on geomembrane

Lrunou,

Ls

=runout Length

=Iength of slope

=angle of shearing resistance of backfill soil

Tallow

~Ol

=allowable ultimate stress of geomembrane

=total force resisting pullout

Dat

a

FL

=depth of anchor trench

=slope angle

=friction force below geomembrane

Pa

Pp

=active earth pressure against the backfill side

=passive earth pressure against the in-situ side

Enter Variables:

lb Tal/ow:= 1512

ft (from product specs)

LrunoUI := 4.3 oft

:=0 odeg Dal :=2 o.ft a:= 18.4 0 deg

Calculate the force resisting pullout:

F =285 lb

L ft

lbFat = 133

ft

lbF101al = 551

/t

(0.5 0 Yeo Da,+ he 0 yo) 0 (tan (45 0_ ~no Da,Pa P =460 lb

a /t

Pp:= (0.5 oy,oDat+hcoy,) o (tan (45 0+ ~noDal P =460 lb

P ft

lb Tallow =1512

ft

The total force resisting pull-out should be slightly less than the maximum allowable pull on the geosynthetic.

500 Designing with Geomembranes Chap. 5

c == (NA tan 0 + Co) sin 13 Sin(~ ; .(3) tan . . (16 + 18.4)= (370 tan 22 + 0) SIll 18.4 sm -'~2- tan 30

8.07kN/m

-b + v'b2= 4ac FS = 2a --

62.8 + vT--6~2.-S)-::-2----4-(3-7.2-)-(S-.07) ;:: ------2(37.2)

FS :=.: 1.55 (vs. 1.25 for the constant thickness cross section)

Example 5.12 has also been extended to a set of de