commendable. However, the question remains whether the overall study plan will be sufficiently flexible to allow for evaluation of alternative plans/procedures if a particular aspect of the original plan is problematical. Articulation of specific hypotheses within the PMP is highly desirable, and this approach should be coupled with a plan that ensures evaluation of results in each step in a timely manner to assure flexibility and implementation of alternative procedures or approaches in place of those that are problematical or do not work.
According to the text and the project schedule summarized in Appendices C and D, this task is already underway. The general description of types of data that will be reviewed and compiled indicates that this should constitute a thorough and comprehensive review of existing information. In addition to examining basic data and reports available from federal, state and local agencies, the inventory should draw on relevant data and reports from the academic community and industry. (These data sources may already be included implicitly in the plan, but the text specifies only “agency” sources.)
The project delivery team should be commended for including this task designed to allow the project to take advantage of new technologies. Based on experience of the Las Vegas Valley Water District (LVVWD) in drilling of ASR wells in karst limestone, dual-wall reverse rotary drilling may be a useful technique. This method provided good return of cuttings and detection of fractures by rig chatter, allowed for drill stem tests and permitted reaming to 12 inches for installation of multi-port or nested monitoring wells. Large diameter (18-inch) flooded reverse circulation produced the highest efficiency ASR wells at LVVWD because vacuum action at the drill bit minimized formation clogging and damage during the drilling process.
This task is a logical first step for utilizing the information compiled in Task 1. Based on the project schedule summarized in Appendices C and D, this task will begin in January 2003, while some of the data compilation efforts of Task 1 are still in progress. This is a reasonable approach to the iterative process of conceptual modeling of the hydrogeologic framework.
As noted in the task description, the initial conceptual model of the hydrogeologic framework can be used in the development of the initial regional numerical model of flow. The project timetable indicates that numerical model development will begin in August 2003, shortly after the scheduled completion of this task in July 2003. It is not clear, however, that this initial conceptual model development will occur in time to aid in siting of pilot ASR wells (as suggested in the task description). According to the timetable listed in Appendix C, the design and permitting of pilot wells (presumably including siting) will be completed in July 2002 for the Lake Okeechobee ASR pilot project, in September 2002 for the Hillsboro pilot project, and in November 2002 for the Caloosahatchee pilot project. Furthermore, the May 2002 Progress