To date, much work has been accomplished in what is nearly a complete rebuild of the tube after the ravages of Sandy. Work trains continue to haul out the heavy debris of the demolished duct banks and concrete walls. With the debris removed, workers are able to inspect the tunnel for leaks and stop them through a chemical grouting injection process. During this process, more than 2,000 of the original bolts holding together the 18-foot diameter cast iron tunnel rings and liner are being replaced with specially manufactured grout bolts. Grouting and bolt replacement to correct the leaks are important elements of this project. Before this project is complete, it is estimated that in excess of 6,000 high-strength steel bolts will be replaced.
Installation work also continues on conduits, steel reinforcement bars and the framework necessary for construction of the new duct bank. To date, more than 2,300 cubic yards of concrete have been poured and nearly 30,000 feet of deteriorated duct banks removed.
The scope of work for the Montague Tube is extensive. The work is being performed in two contracts. The first contract involves the repair of all right-of-way components, except for signals. The second encompasses repair of the signaling equipment. Work on both contracts will be carried out during the tube's closure. The rehabilitation is estimated to cost $308 million in total, with $220 million invested in the right-of-way repairs.