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Bioreactor Landfill Operations Regulatory Perspective Considerations ASTSWMO Conference July 23, 2003Scott Walker, PE, CEGCalifornia EPA Integrated Waste Management Board

MSW landfill operating criteria

Operations regulatory issues for Bioreactor LFs

Operations regulatory performance to date

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MSW Landfill Operating Criteria (40 CFR 258 Subpart C)

Operating requirements pertain to routine operation, management, and record keeping (as distinct from siting; design; ground water monitoring and corrective action; and closure/postclosure).

§258.20-258.29: hazardous waste exclusion; cover material; disease vector; explosive gas; air criteria; access; run-on/-off; surface water; liquid restrictions; record keeping.

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Operating Criteria (cont.)

Many Subtitle D approved state programs incorporate these criteria into additional and more stringent State operating criteria (e.g. CA- 27 CCR).

State permits typically also include site-specific conditions on landfill operations and detailed operations plans incorporated by reference (e.g. CA- SWFP/WDRs Permits and JTD).

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Operations Regulatory Issues for Bioreactor Landfills

Adding liquids and air and operating as Bioreactor Landfill (BL) adds complexity and costs to operations as compared to conventional LF.

As a result, there may be significant increased potential for violations, public nuisances, and short-term risk to public health, safety and environment.

Leachate recirculation for disposal purposes provides some experience for operations regulatory issues.

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Operations Regulatory Issues for Bioreactor Landfills (cont.)

Main topics for discussion: Landfill Gas Control (explosive gas; odors; air emissions)

(topic of next presentation by Pat Sullivan)

Leachate Control (seeps and spills)

Cover Material and Alternative Daily Cover (ADC);

Fire Control (aerobic systems)

Liquid Wastes and Sludges

Implementation of Operations Plans

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Leachate Control

Leachate control is required to prevent public contact and surface water contamination.

Adding liquids and recirculating leachate increases potential for uncontrolled release of leachate from:

Leachate surface “seeps” (breakouts and ponding) from fill area

Spills from breaks or failures in leachate collection and removal system and liquids conveyance system

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Leachate Seep

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Cover Material and ADC

Low permeability daily and intermediate cover soil material impedes uniform distribution of liquids and may contribute to leachate seeps.

States may approve ADC (tarps, green waste, spray-on products, sludge, and others).

ADC with degradable organics added benefit for BLs.

Performance requirements: control vectors, fires, odors, litter, and scavenging. ADC use has its own regulatory issues irrespective of BL.

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Cover Material Issue: Uncontrolled excavations for gas collection or liquids distribution systems

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Fire Control

Aerobic BL systems produce additional heat and add oxygen, which could increase risk of spontaneous combustion and landfill fire.

Critical mitigating factors include monitoring of temperature and control of liquid and air addition, and methane suppression.

To date no fires have occurred within aerobic systems.

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Liquid Wastes and Sludges

Liquid wastes and sludges for BLs provide beneficial sources of moisture and degradable organics, are attractive revenue sources, and may be an indirect environmental benefit for managing these waste types.

May include sewage sludges and WWTP effluent, septage, food-processing wastes, stormwater, brines.

Operations and permit regulatory issues (odors; vectors; worker health & safety) may prevent use.

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Leachate recirculation field case: issues with leachate control; cover material; liquid wastes and sludges

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Leachate recirculation field case (cont.)

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Implementation of Regulatory Operations Plans

Regulatory operations plans document specific procedures to ensure regulatory requirements will be met during operations.

Example for CA- Joint Technical Document (JTD) (27 CCR 21585-21590)

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Implementation of Regulatory Operations Plans (cont.)

Operations plans must integrate with design and construction activities and entire operator team.

Not uncommon for conflicts between: prepared plan and what is implemented; design/construction vs. operations; and regulatory plans vs. business plans.

Operations and design/construction complexity for BLs as compared with conventional LF may increase likelihood for conflicts and lead to violations.

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Projects to Assess Operations Regulatory Performance To Date

Full-scale BL demonstration projects:

USEPA XL Projects: Yolo Co. CA; Maplewood & King George Va; Buncombe Co. NC

USEPA CRADA: WMI Outerloop Ky

Non-USEPA lead: New River Regional Fl; Williamson Co. Tn (Aerobic); Bluestem IA; Sainte Sophie Quebec, Canada

SWANA estimates 20 total BL full-scale projects (distinct from 100+ leachate recirculation)

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Summary and conclusions Additional information:

State program contacts with active projects (ASTSWMO)

USEPA Bioreactor LF Website & developing guidance (EPA State-of-the-Practice Bioreactor Landfill Study)Proceedings: USEPA Workshop on Bioreactor Landfills (2/03)

Bolton: Handbook of Landfill Operations (1995)

SWANA Solid Waste Manager’s Guide to Bioreactor Landfills (10/02) SWANA Annual Landfill Symposium Proceedings (2001; 2002) Under development: SWANA Certification Program of Managers of Bioreactor Landfills

Bioreactor Landfill Operations Regulatory Perspective Considerations