Memo on draft disposal plans, Oct 2001

NYC 9/11 Public Portal Document

Dust Control Evaluation Summary October 11, 2001

• Soybean oil. • Adhesives, including lignin derivative, tree resin emulsions, and synthetic polymer emulsions, which bind particles together. • Foams that encapsulate particles with minimum moisture addition.

Chemical dust suppressants are typically applied by mobile and/or stationary equipment, using spray nozzles. Chemical dust suppressants may be applied to roadways, existing debris stock piles, and other work areas. It is likely that different chemical dust suppressants may be appropriate for different application.

ALTERNATIVES COMPARISON

Water and alternative chemical dust suppressants are compared in the following table:

Type of Source Functional Performance Performance Worker Chemical Mechanism Advantages Limitations Exposure Suppressant Considerations Water Surface or Moisture wets Readily available, Frequent Generation of groundwater particles, low co^, easy to applications may be surface water runoff increasing apply necessary; mass and overapplication may binding them result in loss of together traction, or erosion; freezes below 32 degF Salts Produced from Attracts and Reduces Effectiveness in arid Dermal and natural salt retains evaporation rate and semi-arid inhalation Irritant; will brine moisture at of surface regions may be degrade leather relative moisture; lowers limited; corrosive to boots humidity equal freezing point of aluminum alloys; to or greater water; increases slightly corrosive to than 29% compacted steel; solubility derraity of road results in leaching material; good soil during heavy penetration; short precipitation; curing times releases heat when mixed in water Lignin Paper industry Acts as Increases dry High solubility may Product-specific Derivatives by-product adhesive strength of soil; result in leaching imparts some during heavy plasticity to road precipitation; surfaces; lowers becomes slippery freezing point of when wet, brittle road surface when dry Tree Resin Emulsions from Acts as Low solubility Requires proper Product-specific Emulsions pine tree resins adhesive minimized weather and time to leachir^and cure; no residual provides degree effectiveness after of surface rebteiding; waterproofing; equipment requires imparls some prompt cleanup to plasticity; high avoid curing of resin bonding strength; in hoses and pipes non-corrodve Synthetic Synthetic Binds soil Applicable to a Requires proper Product-specific Polymer formulations particles range of dust weather conditions Emulsions composed of together by emission sources; and time to cure; polyvinyl forming a functions well in may be subJed to acetates, vinyl polymerizing sarxiysoil; UV degradation; acrylic matrix, funcfion increases load­ application copolymers, similar to bearing strength equipment requires copolymer adhesives of roadway timely cleaning; no methacrylates. residual

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