Music city showdown: a Nashville project studies the benefits of re-using segregated and salvaged materials - Demolition Trends

Recycling Today, Feb, 2003 by Bob Brickner

Based on their proposal, Levy estimated a total of 12,400 cubic yards of fill materials would be generated from the buildings, including their foundations. With an established value of $9.00 per cubic yard, upfront cooperation on keeping the material on site and having it reduced by the demolition company to meet the specifications of the construction contractors saved the two projects an estimated $111,600.

During final contract negotiations, Ray Bell decided to use another demolition firm for its project, while Metro did contract with Levy for handling the Guardian Building No. 2.

The TDOT-Ray Bell Gateway Project generated approximately 11,800 cubic yards of "fill material" that was reduced to specifications and left on the Work Zone site. Another 3,800 cubic yards of fill material was hauled off site.

The C&D material hauled to landfill was 3,720 cubic yards. Additionally, the TDOT-related Projects generated approximately 122.5 tons of concrete reinforcing bar and 254 tons of scrap metal. All of this metal was recycled. Another 150 tons of metal and rebar was recycled from the Metro DES building, with approximately 600 cubic yards of materials landfilled.

Metro was very pleased with the overall savings associated with the "selective demolition" project that was created because of the ability to understand the "future needs" of the follow-on new construction contractors of both the Gateway Bridge and the Metro DES project. Without a demolition-new construction coordinator, the demolition company may have removed all materials, including footers down to subgrade, and left a "clean site" for the two new construction companies, potentially at a cost $58,750 higher than proposed.

While it would have been nice to preserve some of the used bricks for reuse at other Metro projects, the current economics within the Nashville area (as determined by this public RFP process) did not justify an extensive brick salvage/ re-use project.

In summary, Metro's commitment to "green demolition" saved Metro an estimated $200,000 ($58,750 on the specific demolition activity plus another $140,000 by eliminating the purchase of off-site fill material for the two projects). GBB estimates that at least 82 percent of the overall volume of materials within the six buildings was re-used as fill material at the DES or contiguous Gateway Bridge site, and more than 525 tons were recovered as scrap metal.

The author is a senior vice president with solid waste and recycling consulting firm Gershman, Brickner & Bratton Inc. (GBB), Fairfax, Va. He can be contacted at bbrickner@gbbinc.com.

General Work Specifications for the DES Project

* All material from such work designated for segregation and/or salvage, to be processed by the demolition contractor into "fill material" or cleaned and stacked in the case of salvaged whole Fed brick was to be removed from the buildings without unnecessary damage in sections or pieces which could be readily transported and processed and/or cleaned to meet typical market conditions and stored and protected by the demolition contractor at specified places within the Project limits.