david dippel, p.g. frank zeng, p.e. waste permits division municipal solid waste permits section...
TRANSCRIPT
Class 1 Cell Design and Development at
Municipal Solid Waste Landfills
David Dippel, P.G.Frank Zeng, P.E.
Waste Permits Division Municipal Solid Waste Permits Section
2015 TCEQ Environmental Trade Fair
Introduction
Authorized MSW Class 1 Locations
Waste Definition and Determination
Location and Operational Restrictions
Design Criteria
Sample Design Drawings
Authorized MSW Class 1 Landfills
Definition 30 TAC 330.3(21)
Industrial solid waste or waste mixture
Concentration, or physical or chemical characteristics is toxic, corrosive, flammable, a strong sensitizer or irritant, a generator of sudden pressure by decomposition, or heat
Present or potential danger to human health or the environment
Class 1 Waste Determination
30 TAC 335.505: A non-hazardous industrial solid waste is a Class 1 waste if:Containing constituents ≥ levels listed in 30 TAC
335.521(a)(1) (Appendix 1, Table 1) IgnitableCorrosiveContaining cyanides ≥ 20 mg/lNot proved to be a Class 2 or Class 3Classified as a Class 1 waste by its generatorIdentified as a Class 1 waste in 30 TAC 335.508
Class 1 Waste Determination
30 TAC 335.508: Classification of Specific Industrial Solid Wastes, such as:Regulated asbestos containing material (RACM)Empty Containers that meet specific criteriaContaminated media containing polychlorinated
biphenyls (PCBs)Wastes with petroleum substances (>1,500 mg/kg)“New chemical substances”, unless demonstrated to
be Class 2 or 3From outside Texas without proper documentationStabilized hazardous wastes that no longer exhibit
hazardous characteristics
Restrictions30TAC 330.173
Not in Type I arid-exempt (AE) landfills (except for RACM)
Must not exceed 20% of total waste (not including Class 1 waste)
Must be accompanied by manifest
Facilities must submit monthly reports to TCEQ
Operational Requirements 30 TAC 330.179
• Inspections• Training• Waste Analysis• Ignitable,
Reactive, or Incompatible
Wastes• Contingency Plans• Operational and
Design Standards
This section provides operational requirements that are referenced in 30 TAC 335 rules, such as:
Location Restrictions 30 TAC 330.561, 335.584, and 330.331(e)(3)
New cells or expansions are prohibited:Barrier islands and peninsulasWithin 1,000 ft of protected shoreline erosionWithin 5,000 ft of unprotected shoreline
erosionIn areas not meeting conditions specified in
335.584(b)(1) and (2), unless an engineered design of equal or greater protection is approved
Design Restrictions30 TAC 335.584(b)(1)
No new cells or expansions in areas where underlying soil unit(s) within five feet of the base of the containment structure, which includes the sides and bottom of the containment structure, have a Unified Soil Classification of GW, GP, GM, GC, SW, SP, or SM, or a hydraulic conductivity > 1 x 10-5 cm/sec, unless:areas where annual evaporation exceeds
annual rainfall by more than 40 inchesthe soil unit is not thick and continuous
enough to provide pathway for waste migration
Design Restrictions30 TAC 335.584(b)(2)
New cells or expansions over regional aquifers must demonstrate:the base of the containment structure
(including sides and bottom) and the aquifer is separated by at least ten feet of material with a hydraulic conductivity towards the aquifer ≤ 10-7 cm/sec
a thicker interval of more permeable material that provides equivalent or greater retardation to pollutant migration
Design Criteria30 TAC 330.331(e)(1)
Applies to MSW landfills accepting Class 1 (other than asbestos-containing wastes):Liner with two components; upper
component minimum 30-mil geomembrane and lower component minimum 3-ft layer of recompacted clay (< 1x10-7 cm/sec)
If HDPE geomembrane; minimum 60-milInstalled in direct, uniform contact with
clayLiner system subject to 330.339 (QC Plan)
Design Criteria30 TAC 330.331(e)(2)
Leachate collection and removal system must:Maintain less than 30-cm leachate over
linerMaterials and strength/thickness that are
chemically resistant prevent collapse under expected pressures
Function through the landfill’s closure and post-closure period
Design Criteria30 TAC 330.457(b)
Final Cover (If no MSW waste placed on top of Class 1
waste) At least 18 inches topsoilA flexible membrane (20 mil or 60 mil if
HDPE)Four feet of compacted clay-rich soil (≤
1x10-7 cm/sec)
Design Criteria30 TAC 330.457(b)
Final Cover(If MSW waste placed above Class 1 Waste)
Must first be covered with a 4-foot layer of compacted clay-rich soil
Installation of final cover meeting requirements of 30 TAC 330.457(a) for MSW only cells
Other Design CriteriaAbove-Grade Disposal of Class 1 Waste
30 TAC 330.179(b)Disposal above natural grade is allowed if
conditions of 30 TAC 335.590(24)(F)(i)-(vi) are met, except as provided by 30 TAC 335.590(24)(F)(vii)
30 TAC 335.590(24)(F)(vii)30 TAC 335.590(24)(F)(ii)-(v) may be exempted if a
satisfactory demonstration is made for meeting 30 TAC 335.590(24)(F)(i) without meeting 30 TAC 335.590(24)(F)(ii)-(v)
Review and approval of above-grade design is on a case-by-case basis, provided that the minimum requirements are met.
Sample Design Drawings
Above-Grade Design30 TAC 330.179(b) & 335.590(24)(F)(i)-(vi)
Alternative Above-Grade Design(Sample)
Design 1 Details(Sample)
Design 2 Details(Sample)
Questions?
