<p><p><strong>Reference(s):</strong></p><p><em>Melton and Gardner (2006)</em></p><p><strong>Method Summary</strong></p><p>While a great deal is already known about groundwater contamination, minimal research has been conducted concerning modeling of impacts from recycled material use in a highway environment. It is hypothesized that the USEPA’s <em>Industrial Waste Management Evaluation Model </em>(IWEM) may aid in the evaluation of whether secondary materials are safe enough for beneficial-use applications in a roadway setting.</p><p><strong>Accuracy and Precision</strong></p><p>Constituent data such as initial concentrations and distribution coefficients (K_ds) are essential information required to perform accurate and successful groundwater modeling of metals.</p><p><strong>Adequacy of Coverage</strong></p><p>The QC/QA methods can be implemented using a reasonable number of tests.</p><p><strong>Implementation Requirements </strong></p><p>Implementation requirements for the QC/QA methods are not excessive.</p><p><strong>General Comments</strong></p><p>IWEM may be useful in a situation where the model predicts that, after a long time (100+ years), adverse groundwater impacts will not result from secondary material leaching. A recommendation for the appropriate use of IWEM may be to use the model for simulating water and solute transport from only representative squares of roadways. For instance, given secondary materials beneath a 6-meter wide roadway, it may be useful to apply IWEM for modeling a 6-meter by 6-meter section of the road.</p></p>