EXAMINATION OF MODERN SANITARY LANDFILLS W. Gregory Vogt Chair, Sanitary Landfill Working Group, ISWA Vice President, SCS Engineers

Major Challenges Acceptance and Approvals for: –Facility Expansions –Siting New Facilities Operational Practices Regulatory Enforcement

Expansions and New Facilities Few New Sites Receive Approvals Public is More Organized Against But Understands the Need Large Expansions and Quarry Fills Stabilization Concerns

Expansions and New Facilities Closure of Poorly Located Sites Large, New Regional Facilities, Larger Equipment, Rail Access Leachate Recirculation Combined with Better Compaction New Landfills Atop Old Landfills New Structures Atop Old Landfills

Biogas Migration Protection

Robust Foundation Designs

California Office Park

Operating Practices Control of Moisture (Liquids) Promoting Run-off Work Areas Cover Application Weather Issues Problem Wastes Environmental Controls (Birds, Dust, Litter, Vectors, Odor) Landfill Biogas

Moisture Control Keep Liquid Wastes Out Good Compaction Reach Final Elevation Quickly Apply Effective Intermediate and Final Cover

Waste In Trench Landfill Trench landfills not approved in most countries

Ponding... Infiltrates the waste mass

Ponding Causes Leachate

Promote Run-Off Eliminate Ponding (Depressions) Divert Water From Wastes Control Run-On

Run-on/Run-off Controls

Run-off Control... By Grade Breaks

Stormwater Interception... Direct Run-off

Flooded Cell... Requires Pumping

Don’t Forget Road Drainage

Run-Off to Sediment Basin

Basin With Run-off

Slope Erosion... Collected

Basin Collects Sediment

Erosion Control — Silt Fence... Impacting Working Face and Compaction

Erosion Control — Rip-rap Ditch

Erosion Control — Jute Matting

Management of Work Areas Controlled Working Face Compaction Cell Construction

Uncontrolled Working Face Poor Compactor Practice

Small Working Face

Compaction Generally Work Up The Slope Keep Layers To 1 Meter - Loose Maintain Proper Slope – 3:1 (Horiz: Vert) Maximum Efficiency: Passes

Compaction Efficiency - Depth Thickness of Layer

Compaction Efficiency With Number Of Passes Number of Passes

Cell Construction Layer Thickness

Cell Construction Working Face Cover

Cell Construction Layer Thickness

Landfill Cover Daily Alternative Daily Covers Intermediate Final

Daily Cover Sanitary Landfill Requires –Control Litter, Odors and Vermin –Fire Protection Generally 15 cm Compacted Soil

Forget the Daily Cover?

Daily Soil Cover Stockpile... Even in the Winter

Alternate Daily Cover (ADC) Foams Slurries Blankets/Tarps Shredded Waste (e.g., Tires) Ash and Residues Contaminated Soils Compost

ADC — Foam Daily Cover

Tarp — On Roller... Note Assistant

Tarp Roller Attachment to Compactor

Intermediate Cover The Same As Daily Cover Plus: –At Least 0.3 meters (Soil) –Reduce Infiltration –Control Gas Migration –Provide “Operating” Surface

Final Cover As Specified In Permit Final Control of Infiltration and Gas Support Vegetative Growth

Landfill Biogas

Monitoring Wells

Biogas Sampling Well

Gas Monitoring Well

Methane and Biogas Meter

Methane Sample Instrument

Biogas Management Options Venting to Atmosphere Flare Burning Incineration (Controlled Process) Recovery as an Energy Source

Active Biogas Control Gas Well Connected to Collection Pipe

Active Collection System

Biogas Extraction Well

Active Biogas Systems Collection Pipe With Supports... Water is Maintenance Item

Active Biogas Systems Blower for Vacuum

Active Biogas Extraction Blowers and Controls

Passive Biogas Systems

Open Pipe Vented to Atmosphere

Potential for Biogas Recovery 1,000,000 Tons of Waste Minimum Site Closed Less Than 5 Years 12 meters Minimum Average Depth Impermeable Cover

LFG Use Options Sale of Generated Electricity Sale as Natural Gas Alternative Burn in Flare Value of Carbon Credits

Electricity From Biogas Large Equipment

Electric Power Units... Or Portable Units

Burn in Flare No Treatment No Energy Recovery Still Requires Water Removal

Enclosed Flare & Candle Flare

Regulatory Enforcement Documents Permits Approved Plans and Specifications Variances Compliance Agreements

Types of Plans Design Plans - Design Engineer Operating Plans - Landfill Manager

Summary Gain Acceptance from the Public Through Use of Good Engineering Design and Regulatory Compliance Design and Operations Must Address Control of All Landfill Issues (odors, contamination) Regulators, Inspectors, and Landfill Operators Should Receive Training