Case Studies

Insitu Stabilization of MGP Impacted Soils Orange and Rockland Utility Co. Nyack, NY P-516

Project Summary

In-situ stabilization in Nyack, New York

This project was performed at a former Manufactured Gas Plant (MGP) site on the banks of the Hudson River in Nyack, New York.  For this phase of the project, In-Situ Stabilization (ISS) work was performed on soils that were impacted by MGP waste. The main contaminants of concern were BTEX and napthalene.  The treatment zone covered approximately 5,500 square feet of surface area with depths from the surface to bedrock ranging from 7 to 20 feet deep.  The project goal was to mix the contaminated soils in-place with a cement-bentonite grout, with the subsequent mixture meeting the treatment criteria of minimum 50 psi unconfined compressive strength @ 28 days and a permeability of 1 x 10-6 cm/sec.

Geo-Solutions teamed with a local contractor to perform the soil mixing work.  For the construction effort, Geo-Solutions provided technical assistance services to the contractor.  Geo-Solutions provided specialty equipment and materials including the Soil Mixing machine with an 8 foot diameter mixing tool, grout mixing plant, special in situ sampler, and all of the required bentonite materials.  Geo-Solutions was also responsible for quality control of the work and the operation of key specialty equipment. 

The project was completed in 2 1/2 weeks.  This met the original construction schedule, even though numerous obstructions including boulders and wooden pilings were encountered throughout the work zone.

Location	Date
Nyack, New York	January to February 2006
References
Client:	Owner: Orange and Rockland Utility Co.
The RETEC Group, inc.
Concord, MA 01742	Spring Valley, NY

Treatment Area Dimensions:

2,500 cy of soil up to 20 ft deep.

Geo-Solutions Can Help

To download, read, and learn more about the various soil mixing sample specs and technical papers we offer online here at Geo-Solutions.com, click on the links below or to your left:

• Soil Mixing Sample Spec– Geo-Solutions provides a soil mixing sample spec which can be modified for real world use on your project. Download sample specification for Soil Mixing .

• Soil Mixing Technical Papers – Browse our library of Soil Mixing Technical Papers.

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