INSPEC36864 - Laserfiche WebLink

Home Browse Search

Asphalt in landfills, from page 12 ~o1ir epplkatlon b cpntroU for ^;", p ` •6ntelletlon, or to upp'rede eM modemlze your exlatlnp plant Seltec tub tM rfpht edWlon. All eyalema ere tnllored la nMel IrxlhAduel plant end contractor repulrartienb -plus prMde Note feeturee required to meal epency approval. From elmple plant control unlta. to compote eyatame...lrom delivery tkkela. to oaks computer Intertece, you can rely on Sellec i expenlae. SELTEC BMG CONJBOL S. INC. 127(7 Ouerry Lene Pleeunlon, CA &1566 TEL (175) ~ZB~7t100 FAX 115) ~-K 76 California toxicity c'nlcria (+rhich arc more stnngent than federal EPA criteria) was Ihat both cxperimenlal (contaminaleJ aggrcg:nc) and control (clean aggregate) pavement "does-not pose a sgndicant em•r ronmental risk." Punhermorc, neuher type of pavement would be classified as hazardous under current Califomia hazardous waste testing protocol. Glenn \Garren, urea president of Applied Environmental Recycling Systems (AERS), of Salem, Alass., also embarked on a research project to assess the relative safety of asphalt in cold mix paving. In order to evaluate leaching proper- ties, samples of hot mix pavements, of cold asphalt emulsions and recycled hot mix asphalt (RAP) were submerged in rainwater. The solids were strained out and the rainwater was tested For contamina- tion. No leaching was detected. Warren then used EPA's toxicity test 1310 to apply an acidic solution to asphalt, designed to mimic conditions in a typical landfill. Again, in the cold mix, hot mix and RAP, levels of leachable pevoleum hydrocarbons were found to be less than one part per million. This level is considered to be negligible, especially when many regulatory agencies have an action level floor of 100 pans per million. Finally, AERS applied the most . recent and most stringent EPA test, method 1311, the Toxic Characteris- tic Leachability Procedure (TCLP). In this case, levels of leachable hydrocarbons were "close to detection limits." This means [he amount of hydrocarbons detected was so small, it barely approached detectable levels. `It is imponant (or users as well as regulatory people to understand there are two aspects to character- ize +vhether something is hazard- ous," says Dr. Karl Eklund, an cm•ironmental consuhanl in Berkley, A1ass `the first compo- nent is the intnnsic chemical composition of asphalt itself Dons u contain elements that pose a health ha 7.arcl to humans? but the second aspect is transport. In what ways does asphalt enter the human s}•slem? Since people don't chew on it, the other possible route is through dunking wafer. And the hazardous components in asphalt cannot be transposed in water." A repon characterizing research about the human health safety of asphalt put out by the American Petroleum Institute back in the 1970s released results of numerous experiments in which asphalt was clearly proved to have low or undetectable links to cancer. According to Dr. Eklund, many states are putting asphalt in a waste disposal category all by itself- calling it "special waste" and banishing it from mixed landfills. "The reason they do not want asphalt in their landfills is only because it takes up so much space, not because it is ha2ardous," says Dr. Eklund. The Asphalt Institute recently published the fmdings of a research investigation initiated by the Illinois Asphalt Pavement Association. Heritage Research Group, of Indianapolis, Ind., tested six different recycled asphalt pave- ments (RAP) to see if it "contained materials that would make it environmentally unsuitable for clean fill." "All the samples met or exceeded the stria EPA guidelines for leachate,' reports Anthony J. Kriech, director of research for the group. Tests were performed in accor- dance with EPA procedures for (TCLP). Some of the findings indicated possible contamination from gasoline or crankcase oils spilled from traffic or accidents when dte road was in use. 'All of these samples met current guidelines for TCLP maximum concentration for the contaminants by characteristic, concludes Kriech. "The results on this represernative group of samples would suggest that KAP is a very safe, non-leachable material."1 Write In SOS for more Information. Write In J97 82 July-August 1991 asphalt contractor