Our project is a 2.2 million SF expansion of an existing conference center in downtown Chicago. The project site has the following key characteristics: 1) it is located approximately 2800 feet from the coast of Lake Michigan; 2) it has been classified as contaminated, per a Phase II Environmental Site Assessment; and 3) its existing imperviousness exceeds 50 percent. The new building will cover 97 percent of the site, with all parking provided in an existing multi-story garage. The non-building site area is primarily sidewalks and vehicle access. To reduce stormwater runoff, approximately 13% of the project\'s roof area will utilize an extensive vegetated roofing system. The project will also include some site landscaping along the perimeter sidewalks. While these two measures will not reduce runoff 25% from existing levels, the project will also include a new 3100 foot stormwater tunnel that will transport the new building\'s roof runoff to Lake Michigan. We are seeking credit equivalency for this combination of strategies, which we believe meets the credit intent to recharge local aquifers, particularly for a site that has soil contamination. The stormwater tunnel is being constructed at the urging of the City of Chicago. The City published a Water Agenda in 2003 that included initiatives to recharge the Great Lakes (the area\'s primary source for drinking water) and to eliminate lake pollution by overflow from the City\'s combined sewer system. To support these initiatives, our project plans to construct the new stormwater tunnel, which will run approximately 150 feet below grade. The Plan has received strong support from the City, as well as The Illinois Environmental Protection Agency (IEPA), Illinois Department of Natural Resource (IDNR), the City of Chicago Department of Environment (CDOE) and the Metropolitan Water Reclamation District of Greater Chicago (MWRD). All of these agencies received the results of water quality tests (taken from the existing convention center roof runoff) demonstrating that the runoff will comply with the applicable water quality discharge standards to the lake. A copy of these test results can be submitted with the credit application. While the tunnel transports stormwater off-site, the stormwater follows the same general path that it would travel were it to infiltrate the ground, due to the proximity of the site to the lake (and a 15\' elevation difference). A key benefit of the tunnel is that it prevents the stormwater from potentially transporting any remaining soil contaminants on the site to the lake (the project scope includes remediation of the Phase II contaminated soil, but current practice promotes some degree of containment rather than complete soil removal and replacement). To summarize, we wish to confirm that the combination of strategies undertaken by this project, in light of its special circumstances, will satisfy the credit intent and requirements.