Elizabeth, New Jersey
Significant Project Features:
- Installation of 242 jet grout columns to a maximum depth of 34 feet below ground surface;
- Jet grouting within 2-feet of active underground utilities.
- Project site was located in an active facility and jet grouting production took place around active construction of new buildings.
- Overhead and underground utilities needed to be protected and worked around.
Geo-Solutions Inc. (GSI) was contracted to complete geotechnical work at a project site in Elizabeth, New Jersey. A former Manufactured Gas Plant was once operational at the site. The purpose of GSI’s work was to create a continuous barrier wall to reduce the flow of contaminates into the groundwater table and/or nearby surface water sources.
Description of Work
Approximately 650 lineal feet of jet grout columns were installed to create the barrier wall. Columns ranged from 4 to 6 feet in diameter and drilling depths ranged from 23 to 34 feet below ground surface. 35 columns were installed within 2 feet of active utilities at varying depths. The utilities included gas, water, and sewage lines. Utilities were exposed prior to jet grouting and PVC casing was installed adjacent to the utilities to be used as a drill guide and utility protection. A Soilmec SM14 drill rig was used to perform the work. A high-pressure jet pump and an automated batch plant were used for creating and sending grout to the drill rig. Spoil trenches were excavated and a vac truck was used for spoil management to maintain a clean site. Wet grab samples and full depth cores were taken during the course of the work. All samples and coring were accepted by the Geotechnical Engineer. The jet grouting portion of the project lasted approximately 1.5 months.