Nyanza Wetland Restoration
Ashland, Massachusetts

The Nyanza Chemical Waste Dump Superfund Site is on Megunko Road in the town of Ashland, Massachusetts.  The Continuous Source Areas include the Eastern Wetland, Trolley Brook, Outfall Creek, and the Lower Raceway. Following remediation efforts by Stone & Webster Engineering, CR Environmental, Inc. provided design and construction oversight for a 5.5 ac “eastern” wetland mitigation and Trolley Brook construction in 1999.  CR restoration specialists reviewed, advised and administered the Army Corp of Engineers’ work plan, and provided onsite construction oversight during the grading, planting and stabilization operations.  The unique aspect of this project was the need to manufacture a wetland soil mixture due to the contamination of the existing organic soils.  Utilizing recycled leaf mulch and sand, the project was able to produce over 7,880 cubic yards of wetland soil mixture.  A number of wetland cover types were constructed including wooded swamp, shrub swamp, marsh, and aquatic plantings.  Additional design amenities included vernal pools, constructed ponds and turtle nesting and basking sites.