Recent concern over the potential environmental impact of highway construction
and repair materials on surface and ground waters has lead to extensive laboratory
screening and subsequent testing of a set of new materials and waste amended mixes. As
part of Phase II of a three-phase project for the National Cooperative Highway Research
Program, a fate and transport model for the assessment of this impact has been written.
The model predicts concentrations and loads of contaminants as well as toxicities for the
leachates in both surface and subsurface environments. The model addresses four
specific "reference environments": an impermeable highway surface, a permeable
highway surface, a vertical piling, and a filled borehole. Six materials are examined in
detail: crumb rubber asphalt concrete. SEMASS asphalt concrete, foundry sand asphalt
concrete, ammonical copper zinc arsenate treated wood, and methyl methacrylate deck
sealer.
A statistical approach to relating toxicity to the concentration of a chemical
"surrogate" forms the basis for prediction of toxicity in the leachates. All fate and
transport prediction methods are based on physical and mathematical descriptions of the
near-highway environment. Surface runoff is calculated using kinematic wave theory
coupled with leaching, photolysis and volatilization, flow through pavement cracks is
based on continuity, and subsurface transport is based on a plug flow model with linear or
Freundlich sorption and biodegradation. Explicit finite difference numerical methods are
used for both surface leaching and subsurface transport. A search engine is provided for
examination of all laboratory results. / Graduation date: 1999
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/33618 |
| Date | 14 April 1998 |
| Creators | Quigley, Marcus M. |
| Contributors | Huber, Wayne C. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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