Description:
The geologic setting of the Maricopa Site is very favorable for rapid and cost-effective
construction of the SSC facility. To correlate geology with tunneling
construction methods, the collider ring was divided into ten Construction Units
(Table 3-1). A Construction Unit may include several different rock types
with varying support requirements but uses a single tunneling construction
method. In some units tunnel excavation and lining will be accomplished exclusively
by tunnel-boring machine (TBM) systems (see Section 3.5.4.2). In
other units either proven cut-and-fill methods or TBM may be used depending
upon the depth of the ring below ground surface (see Section 3.5.4.1). The
ideal geologic conditions not only allow construction of the coIlider ring in a
near surface plane tilted 0.30 from the horizontal, but also provide considerable
flexibility for relocation of the proposed ring alignment or for location of future
additions to the facility if desired by DOE. The injector complex, experimental
chambers, and future facility additions can be built with cut-and-fill methods.
Construction problems are not anticipated from geotechnical factors such as
collapse-susceptible soils, seismic events (natural or man made), ground water,
regional subsidence, expansive clays, or naturally-occurring gases