CONTRIBUTION OF COMMONLY-USED BUILDING MATERIALS TO WET WEATHER POLLUTION

摘要

A literature review of urban stormwater runoff and building/construction materials, especially those commonly used in both commercial and industrial construction, has shown that many materials such as galvanized metal, concrete, asphalt, and wood products, have the potential to release pollutants into urban stormwater runoff and snowmelt. However, much of this previous research cannot be directly applied to estimating pollutant loadings from runoff. One limitation is that the studies were not performed using actual stormwater. A second limitation is that they did not mimic the cyclic wet-dry weathering to which these materials are exposed. The weathering phenomena, which may result in the weakening of the strength of the materials, may significantly impact the release of these pollutants. This paper will discuss an ongoing research project that is investigating pollutant releases from typical construction materials. The first part of this project was designed to investigate, through the use of TCLP testing, the potential for pollutant release. Results of particular interest include evidence of elevated levels of phosphate, nitrate and ammonia in runoff following exposure to common roofing and siding materials, resulting in an unexpectedly high eutrophication potential. Elevated levels of semi-volatile organics and metals are also of concern due to the potential for ecological toxicity. During the second project phase, long-term field tests are being conducted on a subset of these materials in order to determine actual pollutant releases under field conditions.