Soil Treatment, Transportation and Disposal
Crosstown Center, Boston, MA
During construction activities at a Brownfield redevelopment site in Boston’s Roxbury neighborhood, the contractor had excavated and stockpiled nearly 16,000 cubic yards of lead impacted soil. Samples taken from the piles failed the Toxicity Characteristic Leaching Procedure (TCLP) test and therefore, if the soil were shipped off-site for disposal, they would have to be considered a Resource Conservation and Recovery Act (RCRA) hazardous waste. The resulting unexpected cost of over $6,000,000 would have made any additional development at the site unprofitable.
Boston Environmental was contracted to provide on-site treatment of the lead impacted soil to render it non-RCRA hazardous and to transport and dispose of the treated materials. In order to meet the previously determined redevelopment construction schedule and avoid liquidated damages, the project, including the additional transportation and disposal of 6,000 yards of non-hazardous debris to clear a treatment area, had to be completed within 12 weeks of mobilization. Work was further complicated by the fact that the site included an operating hotel, an active parking garage and several businesses whose operations could not be interrupted by the site work.
Prior to beginning treatment, Boston Environmental worked closely with in-and-out-of-state disposal facilities to obtain waste disposal authorizations pending the results of confirmatory sampling and analysis. Over the next eight weeks, treatment, de-characterization and shipment of 21,000 tons of lead impacted soil for off-site disposal occurred.
Soil was mined from the stockpile based on pre-characterization analysis and was treated with a proprietary liquid treatment technology in 500 ton batches. To meet the disposal facilities requirements, the batches were further broken down into 250 ton segments and composite samples were taken of each of these segments and analyzed for TCLP lead and total lead to ensure successful de-characterization and determine the most effective disposal facility. Based on the results and the pre-characterization analysis, the soil was transported to a final disposal site.
The project was completed ahead of schedule in less than eight weeks with treatment production rates of up to 1,200 tons per day with a reduction of leachable lead of up to 99.9999%.
Using stabilization/de-characterization instead of disposing of the soil as a hazardous waste, the developer saved over $4,500,000.
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