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Section 5 Formulation of Alternative Plans

EAA Storage Reservoirs Revised Draft PIR and EIS February 2006

5-59

implementation, including land acquisition, project construction, and operations

and maintenance (O&M) activities, and (2) operation of the modified C&SF

system. As in the case of the NED effects, the OSE account is concerned with

the net effects of the alternative plans (i.e., the differences between the with-

and without-project future conditions).

5.4.5.7 Real Estate Considerations

Evaluation of Real Estate considerations is based on the number of parcels to be

acquired for different reservoir footprints, escalating land values, and sponsor

ability to acquire parcels. The ranking of the alternatives are uniform across

each of the real estate factors.

5.4.5.8 Construction Risk & Uncertainty

Risk and uncertainty effects associated with planning, design and constructing

the EAA reservoirs are identified in each alternative with sensitivity to methods

and materials to be used for the identified alternative. A listing of the specific

risk and uncertainties have been developed for identification and ranking where

numerical measures are available to support their evaluation. For

simplification, these effects are identified as Construction Risk and Uncertainty.

The following information details are provided in support of the numerical

ranking provided in the table.

Experience and contractor availability is rated higher for Earthen Embankment

construction due to the larger number of experienced heavy construction

contractors in the region. RCC is rated slightly lower even though credible and

capable contractors would be expected to respond. Several regional and also

national contractors may be attracted for the scope of work defined for all plans.

Level of difficulty - contractors will incur higher risk and uncertainty in pricing

and performance for RCC compared to Earthen Embankment. RCC is still

considered a developing technology and is much more sensitive for QA/QC,

particularly with regard to mix control (processing aggregate and fines) and

moisture control. Placement techniques are to be developed in greater detail;

i.e., use of forms and slope placement for three ~8.66-foot steps. RCC has been

developing with broader usage over the past decade and a half. Originally

developed for severe and intensive applications such as intermodal shipping and

forestry operations and military tank trails and staging areas; it is widely used

in dam structures as it will be with EAA. Earthen Embankment is given an

edge due to simplicity, but it remains material quantity sensitive with higher

costs than RCC.

Volatility of availability and cost for cement is identified as a significant risk for

RCC. Cement is only available from large regional suppliers such as Titan

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