Chair announced that the Recommended Conceptual Study Plan has come forward from the Working Group meeting and today's meeting has a single purpose: to present and discuss the Study Plan. He pointed out that the Plan is available on the website and has been so for the past two weeks. Chair recognized website work by Larry Keegan and his quick posting of the report. Chair also recognized that two sets of meeting minutes, the sixth and fifth, still remain unapproved.

Chair recognized John Cox, Chairman of Working Group Committee, to present to the full Aquifer Committee the Recommended Conceptual Study Plan

6.1 John Cox, Chairman of the Working Group Committee, provided an overview of work accomplished by the committee and provided the Aquifer Committee with hard copies of the Recommended Conceptual Study Plan. All comments, iterations and opinions, whether accepted or declined by the Working Group, are available from the minutes from the group. Acknowledged are the works of Jim Reichard, Jim Henry, Camille Ransom III, Rick Krause, Jim Landmeyer, Harold Gill, Bill McLemore, Card Smith, John Clarke, and two guest presenters, Fred Falls and Lynn Torak, both of the USGS.

6.2 Outline of the report was presented. (a). Overview of the purpose and history of the Working Group. (b). Summary of technical concerns recommended to the Aquifer Committee. (c). Summary of previous studies. (d). Overview of Working Group technical approach. (e). Recommended technical approach identified as numbered Tasks 1 through Task 6.

6.3 Purpose and history of working group presentation. (a). Formed in response to concerns regarding the hydraulic integrity of the Upper Floridan confining unit. (b). Working Group was formed to directly support the Aquifer Committee's mission statement. (c). Working Group met and determined the relevant technical concerns on March 13-14, 2001 and presented these concerns to Aquifer Committee on April 20, 2001. These technical concerns were approved unanimously by AC. (d). Working Group presented a status report to SEG on May 1, 2001. (e). Working Group reconvened July 24-25, 2001 and identified ten study tasks and designed an initial Draft Study Plan for distribution. (f). Working Group met December 6, 2001 to discuss Draft Study Plan. (g). Six work tasks were retained for inclusion. Further discussion on this topic regarding six tasks followed presentation. Both in-situ testing tasks will be included into the final approved Conceptual Study Plan taking total tasks to eight.

6.4 Overview of Technical Approach.

6.5 Identification of Multiple Tasks:

6.5.1 Task 1: Seismic Reflection Survey
6.5.2 Task 2: Geologic Transect
6.5.3 Task 3: Construct Monitoring Well Clusters
6.5.4 Task 4: In-Channel Exploratory Drilling
6.5.5 Task 5: Compile Database
6.5.6 Task 6: Develop Numerical Model of the Hydrologic System Including and Underlying the Navigation Channel.

6.6 Whereas the tasks as identified 1 through 6 were accepted with minimal discussion, disagreement or concern, a lengthy discussion ensued regarding the hydrogeologic importance of two additional tasks not identified in the Study Plan but that had been discussed by the Working Group at the December 6, 2001 meeting. These two additional, but deleted by majority vote during theDecember 6 meeting, tasks are according to the language and discussion as originally written and described, original Tasks # 4 and # 5, to:

6.6.1 Conduct in-situ hydraulic test of the Upper Floridan confining unit.

Approach: A pumping well would be installed at Ft. Pulaski transect site in addition to the monitoring well cluster. The pumping well would be open to the uppermost water-bearing part of the Upper Floridan aquifer. Well specifications for the pumping well would be developed upon further review of the lithologic data obtained during completion of Task 2.

After installation of monitoring well clusters (or pressure transducer array) and the pumping well, an in-situ hydraulic test of the Upper Floridan confining unit would be conducted by pumping water from the uppermost part of the Upper Floridan aquifer and monitoring head changes within each monitoring well (or pressure transducer) and the pumping well. The duration and rate of pumping of the Upper Floridan aquifer necessary to induce measurable hydraulic responses within the confining are unknown at this time. The pumping rate and duration needed to induce a measurable response would be estimated during the actual design phase of the aquitard test and be based on reasonable estimates of vertical-hydraulic conductivity and storativity of the confining unit.

Rationale-The Minority Position of Working Group members for conducting in-situ hydraulic test of the Upper Floridan confining unit:

(1) vertical hydraulic conductivity is a scale dependent parameter;
(2) aquitard tests are recognized as the best approach to determining estimates of vertical hydraulic conductivity; (3) laboratory-derived estimates of vertical hydraulic conductivity are less representative of field conditions than are aquitard tests;
(4) the cost associated with conducting aquitard tests is nominal; and
(5) aquitard testing is the best approach to determine vertical hydraulic conductivity, which was deemed a critical parameter by the entire Working Group.

6.6.2 Evaluate and analyze in-situ hydraulic test data.

Discussion: Hayes (1979) calculated the vertical hydraulic conductivity of the Upper Floridan confining unit using aquifer tests data from the Burton, South Carolina well field and Port Royal Clay Company well (both on Port Royal Island, South Carolina) using the Hantush-Jacob method. His analyses yielded values of 5.0 E-3 feet/day and 1.5 E-2 feet/day. Smith (1987) compared the vertical hydraulic conductivity values determined from these tests with falling-head permeameter tests of 23 Hawthorn Formation (part of the Upper Floridan aquifer confining unit) samples, having lithologies described as sandy clay and clayey sands, collected from eight sites beneath Port Royal Sound. Although the results of the permeameter analyses ranged over four orders of magnitude, the mode and the median vertical hydraulic conductivity values of the 23 samples were between the vertical hydraulic conductivity values calculated from the aquifer tests.

Approach: The field data collected during the in-situ hydraulic tests will be reduced and analyzed using an appropriate method such as Hantush-Jacob (Lohman, 1979), Newman-Witherspoon (1972), or others. The data analysis would be completed to determine estimates of the vertical hydraulic conductivity of the Upper Floridan confining unit that account for any secondary vertical permeability enhancement such as inter-connected, vertically oriented, fractures and/or joints. It will be necessary to account for background noise and interference from pumping, and barometric and tidal changes and fluctuations during the test and in the analysis of the data.

The initial in-situ hydraulic test would be evaluated to determine the feasibility and necessity of conducting additional tests at other locations along the geologic transect. Should the initial aquitard test be successful in eliciting a measurable head response, thereby allowing vertical-hydraulic conductivity to be computed, additional aquitard tests should then be performed at other sites. Field testing would cease following the first unsuccessful test, or following the fourth or fifth successful one. (i.e. about 4-5 tests should be sufficient to complete this task and meet study objectives.) If the field vertical-hydraulic conductivity values are different than the lab-derived data, then a correlation factor will be applied to the existing lab-derived data.

6.7 Two slides from the presentation are attached as addendums to the meeting minutes. Head characteristics pre and post development, and hydrogeologic section as viewed from the ocean toward land.

6.8 Question and answer period with discussion.

6.8.1 Question was asked why in-situ testing was removed from the recommended tasks. Discussion as to the pros and cons. Fred Rich recommends that the tasks deleted on December 6, 2001 by Working Group be reinserted. Aquifer Committee decided by consensus (save one-John Cox)that in-situ testing will be included as part of the final Conceptual Plan. Wording of the two tasks will be disseminated by email to the Working Group A minority opinion will be submitted for the record.

6.9 Comment was made that when the studies to determine the Kv value (vertical hydraulic conductivity) must take into account the potential development of Jasper County port and the consequent impact of its dredging on the Floridan aquifer.

6.10 Ben Brewton provided the Aquifer Committee a report from Golder and Assoc. on the methods to determine vertical leakage. Submitted report to the Aquifer Committee with notice to paragraph 3.2 of the Golder report. Attached as an addendum. ( Chris, if you fax it to Pam's number I will scan it and make a digital document out of it.)

6.11 Final version of the Conceptual Study Plan will be posted on the website for Aquifer Committee review prior to the June SEG meeting.

6.12 Chair will distribute information.

6.13 Aquifer Committee recognized John Cox for his great work as Working Group Committee Chair.