Environmental — Paper Sludge Lagoon Closures

WINCHESTER, NH — TFCI was the heavy/civil site contractor for the closure of three sludge lagoons at a former paper mill facility in Winchester, New Hampshire. After the lagoons were dewatered, approximately 4,000 cubic yards of wet lagoon sludge was excavated, dewatered, blended and returned to the lagoon footprint during the closure process. The 4,000 cubic yards of wet sludge was approximately 3,000 cubic yards more than originally anticipated but TFCI was able to creatively and successfully pile and blend the material into workable fill without the addition of cost-prohibitive amendments.

In addition to the wet lagoon sludge, TFCI excavated approximately 30,000 cubic yards of sludge that had been previously removed and placed on the steep slopes adjacent to the lagoons (the anticipated quantity had been 18,000 cubic yards). Some of this sludge was used in a blend with the wet lagoon sludge and the remainder was used as lagoon fill material during the closure process. The lagoons were capped with clean sand and topsoil layers underlain by a geosynthetic barrier. Even with all of the major quantity increases, TFCI still completed the project within the original construction window.