scope:

This work must consist of excavation and disposal of all material within the rock tunnel limits indicated on the plans, in accordance with these specifications and in conformity to the lines, grades, stations and tolerances shown on the plans or as established in the field by the Contracting Officer. Some general guidelines to maintain the inherent strength of the ground surrounding the tunnel opening have been included. In addition, the work also includes geotechnical instrumentation for monitoring rock displacement and water management in the tunnel; including but not limited to, furnishing, installing, and monitoring of optical survey targets in the tunnel, collection and interpretation of data and furnishing all other necessary material, equipment and labor incidental to such work, [furnishing of optical survey targets], including installation and monitoring of instruments in accordance with the specifications. The Contractor must monitor all geotechnical instrumentation and interpret the data obtained from them. The data must be made available to the Contracting Officer [upon request][within 24 hours of reading].

The breakage of rock and hard/unyielding materials may be conducted by any means unless otherwise stated herein. If the contractor elects to use drilling and blasting for breakage or displacement of units, this entire section is applicable and covers activities associated with drilling and blasting for rock excavation at the surface for portal and shaft construction, or underground tunneling operations. Contained herein are procedures for all activities relating to drilling; blasting and the transportation, storage and use of explosives; breakage and displacement of rock. The Contractor's blasting program and methods are those necessary to accomplish the excavation shown on the Contract drawings in accordance with the provisions specified herein. Contractor's blasting plan must address site-specific conditions affecting the control, quantity, and magnitude of explosives fired in all blasting operations to prevent injuries to persons and avoid damage to all structures, properties, governmental and nonprofit entities, commerce and businesses, and natural resources and their habitat.