Project Work Plan

Study Title: Linking a conceptual karst hydrogeologic model of the Biscayne aquifer to ground-water flow simulations from Everglades National Park to Biscayne National Park-Phase 1
Study Start Date: Oct. 1, 2005 Study End Date: Sept. 30, 2009
Web Sites: See http://sofia.usgs.gov/projects/karst_model/ for project information and http://sofia.usgs.gov/people/cunningham.html for information on principal investigator.
Location (Subregions, Counties, Park or Refuge): SE Florida, Miami-Dade County, includes ENP & BNP
Funding Source: USGS Greater Everglades Priority Ecosystems Science (GE PES) and ENP Critical Ecosystems Studies Initiative (CESI)
Other Complementary Funding Source: None
Funding History: FY06, FY07, FY08, Anticipated FY09
Principal Investigator: Kevin J. Cunningham
Study Personnel: Melinda A. Wolfert, Christian D. Langevin, Michael A. Wacker, G. Lynn Wingard, Edward Robinson, Joann F. Dixon, Lee J. Florea, Michael C. Sukop, Jeff Lee, W. Barclay Shoemaker, H. Allen Curran, Cameron Walker
Supporting Organizations: USGS Mendenhall Postdoctoral Program
Associated / Linked Studies: Biscayne Bay Coastal Wetlands Project, L31N/L30 Seepage Management Pilot Project, Everglades National Park Seepage Management Project, Water Conservation Area 3 Decompartmentalization and Sheetflow Enhancement Project, Lake Belt In-Ground Reservoir Technology Pilot Project, and Landscape-Scale Science Needed to Support Multiple CERP Projects.

Overview & Objectives: Research is needed to determine how planned CERP seepage control actions within the triple-porosity karstic Biscayne aquifer in the general area of Northeast Shark Slough will affect ground-water flows and recharge between the Everglades wetlands and Biscayne Bay. A fundamental problem in the simulation of karst ground-water flow and solute transport is how best to represent aquifer heterogeneity as defined by the spatial distribution of porosity, permeability, and storage. The triple porosity of the Biscayne aquifer is principally: (1) matrix of interparticle and separate-vug porosity, providing much of the storage and, under dynamic conditions, diffuse-carbonate flow; (2) touching-vug porosity creating stratiform ground-water flow passageways; and (3) less common conduit porosity composed mainly of bedding plane vugs, thin solution pipes, and cavernous vugs. The objectives of this project are to: (1) build on the Lake Belt area hydrogeologic framework (recently completed by the principal investigator), mainly using cyclostratigraphic and borehole geophysical methods to map porosity types and develop the triple-porosity karst framework between the Everglades wetlands and Biscayne Bay and (2) develop procedures for numerical simulation of ground-water flow within the Biscayne aquifer multi-porosity system. Technologies developed in this program are novel and will be applicable to integrated science approaches needed by decision makers for adaptive management of ecosystems.

Specific Relevance to Major Unanswered Questions and Information Needs Identified: This study supports the new USGS Science Strategy (USGS Circular 1309; 2007) by helping to develop a Water Census of the south Florida by providing new methods to link hydrogeology and aquifer characterization to ground-water modeling to be used for (1) a more precise determination of water use for meeting future human, environmental, and wildlife needs, and (2) establishing how freshwater is related to natural storage and movement of water, as well as engineered systems, water use, and related transfers. Further, this study supports the USGS Science Strategy by Leveraging Evolving Technologies in the areas of (1) paleobiology and its relation to fresh ground-water flow, (2) borehole geophysics (eg., digital optical borehole imaging), (3) surface geophysics (high-resolution marine seismic in Biscayne National Park), (4) 3-dimensional visualizations products of aquifer characteristics, (5) new hydraulic modeling technologies such as lattice Boltzmann methods, (6) computerized tomographic (CT) computer renderings of aquifer materials, (7) magnetic resonance imaging (MRI) of fluid flow in 3-dimensional models of aquifer materials, (8) building strong partnerships with University students and professors at Florida International University and Smith College, which are critical to advancing USGS science capabilities, and (9) building partnerships within the USGS through use of USGS Mendenhall Postdoctoral Program for conducting novel research.

This study provides support to a related GE PES-CESI study in progress by Melinda Lohmann titled "Coupled Surface Water and Ground Water Model to Simulate Past, Present and Future Hydrologic Conditions in DOI Managed Lands" by providing a new hydrogeologic framework between Everglades National Park and Biscayne National Park for future modeling efforts by Lohmann. This study supports several projects listed in the DOI science plan (specifically: Biscayne Bay Coastal Wetlands Project, L31N/L30 Seepage Management Pilot Project, Everglades National Park Seepage Management Project, Water Conservation Area 3 Decompartmentalization and Sheetflow Enhancement project, Lake Belt In-Ground Reservoir Technology Pilot Project, and Landscape-Scale Science Needed to Support Multiple CERP Projects) by including development of procedures for numerical simulations of ground-water flow in the karst Biscayne aquifer from the Northeast Shark Slough area, where the CERP L31N/L30 Seepage Management Pilot Project and Everglades National Park Seepage Management Projects will alter current hydropatterns in ENP, and seepage to the east. The development of an expanded conceptual karst hydrogeologic framework planned in this proposal will be used to assist development of procedures for numeric simulations to improve the monitoring and assessment of the response of the ground-water system to hydrologic changes caused by seepage-management pilot project implementation. Specifically, the development of procedures for ground-water modeling of the karst Biscayne aquifer in the area of Northern Shark Slough will help determine the appropriate hydrologic response to rainfall and translate that information into appropriate performance targets for input into the design and operating rules to manage water levels and flow volumes for the two Seepage Management Areas. Mapping of the karstic stratiform ground-water flow passageways in the Biscayne aquifer is recent and limited to a small area of Miami-Dade County adjacent to the Everglades wetlands (Cunningham and others, 2006 a,b). Extension of this karst framework between the Everglades wetlands and coastal Biscayne Bay will aid in the simulation of coupled ground-water and surface-water flows to Biscayne Bay. The development of procedures for modeling in the karst Biscayne aquifer will useful to the establishment of minimum flows and levels to the bay and seasonal flow patterns. Also, these improved procedures for simulations will assist in ecologic modeling efforts of Biscayne Bay coastal estuaries.

This study supports the Biscayne Bay Coastal Wetlands project (BBCW p. 83-84) as it (1) will provide a new karst hydrogeologic framework of the Biscayne aquifer that will be used in development of new procedures for hydrologic modeling in the karst Biscayne aquifer that includes areas adjacent to and within Biscayne Bay; (2) provides data and development of procedures for hydrologic modeling that will be useful in establishing and managing water quality performance targets in Biscayne Bay; and (3) provides data and development of procedures for hydrologic modeling that can be used in research to understand the links between the hydrology and ecology of Biscayne Bay.

This study supports the L-31N/L30 Seepage Management Pilot project and Everglades National Park Seepage Management project (L-31N/L-30N SMPP and ENP SM p. 55-56) as it (1) provides wells and development of procedures for modeling in the karst Biscayne aquifer that will benefit monitoring and assessment of the pilot projects information needs; (2) produces wells, a high-resolution hydrogeologic framework, and development of procedures for hydrologic modeling that can be used in research and possible model refinement to establish operating protocols of the seepage barriers; (3) produces wells, a high-resolution hydrogeologic framework, and procedures for hydrologic modeling that can be used by researchers to define how back pumping and ground-water hydraulic gradients affect the flow of water and ground-water recharge in the surficial aquifer; and (4) produces wells, a high-resolution hydrogeologic framework, and procedures for hydrologic modeling in the karst Biscayne aquifer that will benefit additional research and modeling that is needed to determine how extensive seepage control actions will affect ground-water flows and recharge within the surficial aquifer and ultimate delivery of ground-water between the Everglades and Biscayne Bay.

This study supports the Water Conservation Area 3 Decompartmentalization and Sheetflow Enhancement project (DECOMP; p. 78-79) as it (1) provides data for research to understand the linkages among the geologic, hydrologic, chemical, climatological, and biological processes that shaped the predrainage Everglades and will produce data that can help to understand and reduce the effects of hydrologic seepage barriers on ecological connectivity and (2) produces data useful in research to understand and reduce the effects of hydrologic barriers on ecological connectivity.

This study supports the Lake Belt In-Ground Reservoir Technology project (p. 52) as it provides information that will be helpful in assessing the effectiveness of seepage barriers needed in construction of Lake Belt reservoirs.

This study supports Landscape-Scale Science Needed to Support Multiple CERP Projects (p. 95-96) as it (1) provides development of procedures for ground-water modeling that is needed to address historical, current, and projected ground-water flows between the Everglades and Biscayne Bay; (2) provides a high-resolution hydrogeologic framework of the karst Biscayne aquifer that will be used development of procedures for higher resolution hydrologic model that can help in the ability to predict how fish and wildlife will respond to a given restoration project; and (3) provides new data and development of procedures for hydrologic modeling that can be useful for further modeling and monitoring of the surficial aquifer for the quantitative assessment and monitoring of seepage into the surficial aquifer.

Status: Ongoing project that started in FY06

Recent Products: Recent relevant publications that are linked to the study area and project goals: (1) Cunningham, K.J., Sukop, M.C., Curran, H.A., Wacker, M.A., and Dixon, J.F., 2008, Biogenic macroporosity in the Biscayne aquifer, southeastern Florida: a new type of Karst: in prep.; (2) Shoemaker, W.B., Cunningham, K.J., Kuniansky, E.L., and Dixon, J.F., 2007, Impacts of turbulence on hydraulic heads and parameter sensitivities in preferential groundwater flow layers: Water Resources Research, in review. (3) Shoemaker W.B., Kuniansky E.L., Birk S., Bauer S and E.D Swain, 2007, Documentation of a Conduit Flow Process for MODFLOW-2005: USGS TM book 6, chap. A24; (4) Alvarez, P.F., 2007, Lattice Boltzmann modeling of fluid flow to determine the permeability of a karst specimen: M.S. Thesis, Florida International University, Miami, 96 p. (5) Cunningham, K.J., and Curran, H.A., 2007, Ichnogenic porosity, high-frequency cyclostratigraphy, and groundwater flow in the karst Biscayne aquifer, SE Florida, USA;: Gingras, M.K., and Zonneveld, J.P.,. eds., International Ichnofabrics Workshop IX, Calgary, Alberta, Canada, August 11-16, Abstracts with Program, p. 12-15; (6) Sukop, M., Langevin, C. and Cunningham, K.J., 2006, Modeling Flow and Solute Transport in Karst Aquifers with Lattice Boltzmann Methods, Eos Transactions American Geophysical Union 87(52), Fall Meeting, Abstract H42C-08; (7) Florea, L.J., and Cunningham, K.J., 2007, Hydrostratigraphy of the Karst Aquifers of Florida: Karst Research Institute-Time in Karst, Short Scientific Paper, Postojna, Slovenia, March 14-18, 3 p.; (8) Florea, L.J., and Cunningham, K.J., 2007, Geochemistry of groundwater within a karstified limestone hammock of Everglades National Park: Geological Society of America Annual Meeting, Oct. 28-31, Denver, CO, GSA Abstracts with Programs, v. 39, no. 6, in press; (9) Sukop, M., Huang, H., Alvarez, P.H., Cunningham, K.J., and C.D. Langevin, 2007, Applying Lattice Boltzmann, fractal, and geostatistical methods to karst: International Workshop on Scale Dependences in Soil and Hydrologic Systems, El Barco de Avila, Spain, July 3-6, PEDOFRACT 2007 Abstracts with Program, p. 18; (10) Sukop, M.C., Alvarez, P.F., Cunningham, K.J., and Langevin, C.D., 2007, Investigating non-Darcy flow in highly porous aquifer materials with lattice Boltzmann methods: Fourth International Conference for Mesoscopic Methods in Engineering and Science, Munich, Germany, July 16-20, Munich, Germany, p. 1; (11) Florea, L.J., and Cunningham, K.J., 2007, Geochemistry within a karstified limestone hammock of Everglades National Park: International Conference on Karst Hydrogeology and Ecosystems, August 13-15, Bowling Green, KY, http://hoffman.wku.edu/karst2007/abstract.html; (12) Cunningham, K.J., Renken, R.A., Wacker, M.A., Zygnerski, M.R., Robinson, E., Shapiro, A.M., and Wingard, G.L., 2006, Application of carbonate cyclostratigraphy and borehole geophysics to delineate porosity and preferential flow in the karst limestone of the Biscayne aquifer, SE Florida, in Harmon, R.S., and Wicks, C., eds., Perspectives on karst geomorphology, hydrology, and geochemistry-A tribute volume to Derek C. Ford and William B. White: Geological Society of America Special Paper 404, p. 191-208; (13) Cunningham, K.J., Wacker, M.A., Robinson, Edward, Dixon, J.F., and Wingard, G.L., 2006, A cyclostratigraphic and borehole geophysical approach to development of a three-dimensional conceptual hydrogeologic model of the karstic Biscayne aquifer, southeastern Florida: U.S. Geological Survey Scientific Investigations Report 2005-5235, 69 p.; (14) Renken, R.A., Shapiro, A.M., Cunningham, K.J., Harvey, R.W., Metge, D.W., Zygnerski, M.R., Osborn, C.L., Wacker, M.A., and Ryan, J.N., 2005, Assessing the vulnerability of a municipal well field to contamination in a karst aquifer: Environmental and Engineering Geoscience, v. 11, no. 4, p. 341-354; (15) Cunningham, K.J., Carlson, J.L., Wingard, G.L., and others, 2004, Characterization of aquifer heterogeneity using cyclostratigraphy and geophysical methods in the upper part of the Biscayne aquifer, southeastern Florida: relation to rock fabric and sequence stratgraphy. U.S. Geological Survey Water-Resources Investigations Report 03-4208, 46 p.; (16) Cunningham, K.J., Wacker, M.A., Robinson, Edward, and others, 2004, Hydrogeology and ground-water flow at Levee-31N, Miami-Dade County, Florida, July 2003 to May 2004. U.S. Geological Survey Scientific Investigations Map I-2846, 1 sheet; (17) Cunningham, K.J., Carlson, J.I., and Hurley, N.F., 2004, New method for quantification of vuggy porosity from digital optical borehole images as applied to the karstic Pleistocene limestone of the Biscayne aquifer, southeastern Florida. Journal of Applied Geophysics: v. 55, p. 77-90; and (18) Cunningham, K.J., 2004, Application of ground-penetrating radar, digital optical borehole images, and cores for characterization of porosity hydraulic conductivity and paleokarst in the Biscayne aquifer, southeastern Florida, USA;. Journal of Applied Geophysics: v. 55, p. 61-76.

Planned Products: Several white-paper articles reporting on results.

WORK PLAN

Title of Task 1: Drilling of one test corehole on Elliott Key or Boca Chita Key, Biscayne National Park, and possibly a second onshore near Alice Wainwright Park, Dade County
Task Funding: USGS Greater Everglades Priority Ecosystems Science (GE PES) and ENP Critical Ecosystems Studies Initiative (CESI)
Task Leaders: Kevin J. Cunningham
Phone: 954-377-5913
FAX: 954-377-5901
Task Status (proposed or active): Proposed
Task priority: High
Task Personnel: Kevin J. Cunningham, Michael A. Wacker, Lee J. Florea

Task Summary and Objectives: Drill and complete at least one test corehole between ENP and into BNP to acquire rock cores and borehole geophysical data critical to developing a high-resolution 3-dimensional karst hydrogeologic framework of the Biscayne aquifer between ENP and into BNP. The framework will be used in the development of modeling procedures to integrate the new conceptual karst hydrogeologic model into simulations of ground-water flow, salt-water intrusion, ground-water and surface-water interactions, and solution transport in the variable-density ground-water model of Miami-Dade County.

Work to be undertaken during the proposal year and a description of the methods and procedures: Drilling and completion of approximately at least one test coreholes by wireline coring methods.

Specific Task Products: At least one test corehole will be installed on Elliott Key or Boca Chita Key in Biscayne National Park and available for research requirements of this study and future research needs, such as, selected samples for use in Computed Tomography (CT-scan) renderings that can be used for quantification of permeability using Lattice-Boltzmann modeling, a critical component of developing ground-water modeling procedures.

By end of second quarter of FY08.

Title of Task 2: Geophysical logging
Task Funding: USGS Greater Everglades Priority Ecosystems Science (GE PES) and ENP Critical Ecosystems Studies Initiative (CESI)
Task Leaders: Kevin J. Cunningham
Phone: 954-377-5913
FAX: 954-377-5901
Task Status (proposed or active): Proposed
Task priority: High
Task Personnel: Kevin J. Cunningham, Michael A. Wacker

Task Summary and Objectives: Acquire advanced geophysical logs (digital borehole image logs, full wave-form sonic, natural gamma ray, 3-arm caliper, fluid resistivity, fluid temperature, spontaneous potential, single-point resistivity, electromagnetic induction, borehole flowmeter) in each of the coreholes completed in Task 1. Data is critical to developing a high-resolution 3-dimensional karst hydrogeologic framework of the Biscayne aquifer between ENP and BNP. The framework will be used in the development of development of modeling procedures to integrate the new conceptual karst hydrogeologic model into simulations of ground-water flow, salt-water intrusion, ground-water and surface-water interactions, and solution transport in the variable-density ground-water model of Miami-Dade County.

Work to be undertaken during the proposal year and a description of the methods and procedures: Acquire geophysical logs at completion of each test corehole in Task 1. Processing of sonic data to be accomplished using LogCruncher software. Use of flowmeter and fluid-temperature and resistivity data assists in selection of preferred ground-water flow paths in the karst Biscayne aquifer. Task will produce data necessary to produce a conceptual karst hydrogeologic model by integrating core analyses, (including molluscan and benthic foraminiferal data and interpretation of lithofacies, ichnofacies, and depositional facies), borehole geophysical logs, cyclostratigraphy, and hydrologic data.

Specific Task Product(s): Digital borehole image log computerized volume renderings can be used for quantification of permeability using Lattice-Boltzmann modeling, a critical component of developing ground-water modeling procedures. Electronic files of geophysical logs will be archived as electronic files at the USGS-FISC-CWRS office, and paper copies and PDF file versions of log montages of all geophysical logs will be produced using WellCAD software.

By end of third quarter of FY08.

Title of Task 3: Cyclostratigraphy and hydrostratigraphy
Task Funding: USGS Greater Everglades Priority Ecosystems Science (GE PES) and ENP Critical Ecosystems Studies Initiative (CESI)
Task Leaders: Kevin J. Cunningham
Phone: 954-377-5913
FAX: 954-377-5901
Task Status (proposed or active): Active
Task priority: High
Task Personnel: Kevin J. Cunningham, Michael A. Wacker, G. Lynn Wingard, Edward Robinson, Joann F. Dixon, H. Allen Curran

Task Summary and Objectives: Develop a new hydrogeologic framework for the karstic Biscayne aquifer between the ENP and BNP. The framework will be used in the development of modeling procedures to integrate the new conceptual karst hydrogeologic model into simulations of ground-water flow, salt-water intrusion, ground-water and surface-water interactions, and solution transport in the variable-density ground-water model of Miami-Dade County.

Work to be undertaken during the proposal year and a description of the methods and procedures: Integrate data from core descriptions, thin-section petrography, paleontology of mollusks and foraminifers, ichnology (trace fossils), construction of hydrogeologic cross sections, and measurement of porosity and permeability of core samples to develop a high-resolution conceptual karst hydrogeologic framework of the Biscayne aquifer in the study area. Task will produce a conceptual karst hydrogeologic model by integrating core analyses, (including molluscan and benthic foraminiferal data and interpretation of lithofacies, ichnofacies, and depositional facies), borehole geophysical logs, cyclostratigraphy, and hydrologic data.

Core samples to be described using a 10-power hand lens and binocular microscope to determine vertical patterns of microfacies, ichnofacies, sedimentary structures, and lithostratigraphic boundaries, to characterize porosity, and to estimate "relative" permeability. Limestones to be classified by combining the schemes of Dunham (1962), Embry and Klovan (1971), and Lucia (1995). Core-sample descriptions to be classified as rock-fabric facies and presented graphically. Horizontal and vertical permeability of numerous whole-core samples and porosity and grain density to be measured at Core Laboratories, Inc., Midland, Texas. Borehole images acquired from each test corehole in Task 1 will be used to quantify vuggy porosity using a method described in Cunningham and others (2004, Journal of Applied Geophysics). Molluscan analyses to be conducted by G. Lynn Wingard at the USGS Paleontology Laboratory in Reston. Core samples will be examined under a binocular microscope to observed diagnostic characteristics and compared to published species. Clay squeezes or latex casts will be made of the molluscan molds where appropriate to aid in identification. Identification of benthic foraminifera to be conducted by Edward Robinson at the University of West Indies. Thin section samples will be examined petrographically to observed diagnostic features for identification of foraminiferal type and associated depositional environments. H. Allen Curran, Smith College, will assist in study of the relation between ichnology and highly permeable ground-water flow zones. Research will include Computed Tomography (CT-scan) digitization of highly permeable ichnofacies from the Biscayne aquifer and core analyses. Dr. Mike Sukop and his PhD candidate Jeff Lee will conduct calculations of porosity and permeability computer renderings of volumes representative of Biscayne aquifer macroporosity and rock matrix created from use of geostatistical and fractal approaches incorporating data from digital borehole images of the full thickness of the Biscayne aquifer and from CT-scanned renderings of rock samples from the Biscayne aquifer.

Specific Task Products: Constuction of two-dimensional hydrogeologic cross sections. Development of a three-dimensional conceptual hydrogeologic framework of area encompassed by approximately 21 new coreholes. Model will be output using Environmental Visualization Systems NT-PRO software. STL files of digitized CT scans of porous limestone for use in VRML software. All tasks to be completed by end of FY09. Results to includes a journal article in preparation and another draft of a journal article.

Title of Task 4: Seismic Interpretation
Task Funding: USGS Greater Everglades Priority Ecosystems Science (GE PES) and ENP Critical Ecosystems Studies Initiative (CESI)
Task Leaders: Kevin J. Cunningham
Phone: 954-377-5917
FAX: 954-377-5901
Task Status (proposed or active): Proposed
Task priority: High
Task Personnel: Kevin J. Cunningham, Cameron Walker, Joann F. Dixon

Task Summary and Objectives: The karst features in the Biscayne aquifer are not totally characterized or their origin fully understood. It is possible that there is a structural influence that plays a role in the development of some of the karst permeability in the Biscayne aquifer and that it is related to faults or fractures that propagate upward from the a deeper level within the Floridan aquifer. These structural features have potential to allow hydraulic connection between the Florida aquifer and the Biscayne aquifer. Investigations need to test the hypothesis that these features exist. Testing this hypothesis with drilling of core holes in Biscayne Bay is expensive and results in a one-dimensional data product. High-resolution marine reflection seismic data is cost effective and will produce a broad two-dimensional view of the hydrogeologic framework beneath Biscayne Bay.

The objectives of this project are to: (1) acquire high-resolution marine reflection seismic data in the general area of Biscayne National Park between Black Point Marina and the seaward side of the chain of islands that include Elliott Key, and (2) interpret the data in the context of testing the hypothesis that deep seated structures could provide a hydrologic connection between the Floridan aquifer and Biscayne aquifer and further have an impact of the development of karst within the limestone of the Biscayne aquifer.

Work to be undertaken during the proposal year and a description of the methods and procedures: In FY07, multi-channel high-resolution marine reflection seismic surveys was run over approximately 65 nautical line-miles (nmi) of program consisting of about 9 lines in Biscayne National Park, and 2 line east of Elliot Key partly outside the Park boundary. This data will be processed and interpreted during FY08. Interpretation with be done using seismic interpretation software on a desktop PC.

Specific Task Products: Draft of white-paper journal article, interpreted seismic sections, and structural maps of key seismic horizons. Results from this project will provide information on the further refinement of the conceptual karst hydrogeologic framework of the Biscayne aquifer within Biscayne Bay, especially Biscayne National Park. This project will improve the ability to quantify current and future ground-water flow from the Everglades wetlands to Biscayne Bay, thereby aiding the restoration, protection, and management of Department of Interior resources at Everglades National Park and Biscayne National Park. Data can be used in ground-water simulations to improve delineation of saltwater intrusion, and rates and quantity of freshwater flows to Biscayne Bay.

By end of FY09.

Title of Task 5: Hydrologic Modeling
Task Funding: USGS Greater Everglades Priority Ecosystems Science (GE PES) and ENP Critical Ecosystems Studies Initiative (CESI)
Task Leaders: Christian D. Langevin, Melinda A. Wolfert, Kevin J. Cunningham
Phone: 954-377-5917
FAX: 954-7-5901
Task Status (proposed or active): Active
Task priority: High
Task Personnel: Christian D. Langevin, Melinda A. Wolfert, Michael C. Sukop, Jeff Lee, W. Barclay Shoemaker, Joann F. Dixon

Task Summary and Objectives: Initiate procedures for the application of the MODFLOW-2000 Hydrogeologic Unit Flow (HUF) pack to hydrologic modeling of the karstic Biscayne aquifer in the study area and quantify macroporosity and permeability of highly porous flow zones of the Biscayne aquifer using lattice Boltzmann modeling. Development of modeling procedures for a karstic aquifer will allow more reliable simulations of ground-water flow, salt-water intrusion, ground-water and surface-water interactions, and solution transport in the variable-density ground-water model of Miami-Dade County.

Work to be undertaken during the proposal year and a description of the methods and procedures: Professor Michael C. Sukop, Florida International University, will supervise PhD candidate and postdoctoral research on the application of lattice Boltzmann modeling to quantify porosity and permeability of recently acquired Computed Tomography (CT-scan) data from limestone rock samples of highly permeable Biscayne aquifer ground-water flow zones. Also, they will conduct calculations of porosity and permeability computer renderings of volumes representative of Biscayne aquifer macroporosity and rock matrix created from use of geostatistical and fractal approaches incorporating data from digital borehole images of the full thickness of the Biscayne aquifer. The results are expected to substantially increase our understanding of flow processes in the multi-porosity karst Biscayne aquifer. Methods are to compute the permeability of important ground-water flow zones in the Biscayne aquifer and simulate flow in different sized computer renderings of aquifer volumes at varying Reynolds numbers. Methods for incorporating the results into large-scale models will be considered.

Initiate integration of porosity and permeability relations into the MODFLOW-2000 Hydrogeologic Unit Flow package and begin application of techniques to apportion the lattice Boltzmann-derived permeability values to individual flow zones. This work supports the Biscayne Bay Coastal Wetlands project (BBCW; p. 83-84) as it provides data and development of protocol for hydrologic modeling in a karstic aquifer that will be useful in establishing and managing water quality performance targets in Biscayne Bay and provides data and a protocol for hydrologic modeling that can be used in research to understand the links between the hydrology and ecology of Biscayne Bay. Continued use of MODFLOW-2005 and the Conduit Flow Process package developed by W. Barclay Shoemaker (USGS), which is currently undergoing testing at CWRS may be continued to be tested for modeling ground-water flow in the Biscayne aquifer, since equivalent porous media models are likely less reliable in linking high permeability ground-water flow paths and low permeability matrix.

This task supports the L-31N/L30 Seepage Management Pilot project and Everglades National Park Seepage Management project (L-31N/L-30N SMPP and ENP SM p. 55-56) as it provides protocol for modeling that will benefit monitoring and assessment of the pilot projects information needs and protocol for hydrologic modeling in a karstic aquifer that will benefit additional research and modeling that is needed to determine how extensive seepage control actions will affect ground-water flows and recharge within the surficial aquifer and ultimate delivery of ground-water between the Everglades and Biscayne Bay. This work supports Landscape-Scale Science Needed to Support Multiple CERP Projects (p. 95-96) as it (1) provides protocol for ground-water modeling in a karstic aquifer that is needed to address historical, current, and projected ground-water flows between the Everglades and Biscayne Bay and (2) provides new data and protocol for hydrologic modeling in a karstic aquifer that can be useful for further modeling and monitoring of the Biscayne aquifer for the quantitative assessment and monitoring of seepage into the surficial aquifer.

Specific Task Products: Quantification of hydraulic conductivity of highly-permeable ground-water flow zone of the Biscayne aquifer using Lattce-Boltzmann modeling. Test use of porosity and permeability relations derived from lattice Boltzmann modeling with the MODFLOW-2000 Hydrogeologic Unit Flow package, and begin application of parameter estimation techniques to apportion the bulk permeability values to individual Biscayne aquifer flow zones. Results to include submittal of one journal article on application of lattice-Boltzmann modeling to calculation of permeability in the Biscayne aquifer. One journal article on the Conduit Flow Process package is in journal review, one USGS report on documentation of the Conduit Flow Process package has been approved for publication, one journal article on integration of lattice Boltzmann modeling and hydrgeologic results is in preparation, and one Master's Thesis at Florida International University on application of lattice Boltzmann modeling to Biscayne aquifer material has been completed.

By end of FY09.

Title of Task 6: USGS Mendenhall Postdoctoral Research
Task Funding: USGS Mendenhall Postdoctoral Program
Task Leaders: Lee J. Florea and Kevin J. Cunningham
Phone: 954-377-5913
FAX: 954-377-5901
Task Status: Active
Task priority: Moderate
Task Personnel: Lee J. Florea

Task Summary and Objectives: Two projects are being undertaken as post-doctoral research. The first investigates the geochemistry, microbiology, and isotopic fractionation of surface water, cave water, and shallow groundwater in a karstified limestone hammock of Everglades National Park. Project is designed to increase understanding of karst processes (especially cave formation) within the Biscayne aquifer between the Everglades National Park and Biscayne National Park and possible role in fresh ground-water flows. A second project explores the use of Magnetic Resonance Imaging (MRI) imaging to quantify the hydraulic properties of groundwater flow through preferred flow units in the Biscayne aquifer.

Work to be undertaken during the proposal year and a description of the methods and procedures: The cave study in Everglades National Park measures and examines 1) the variation of the calcite saturation index through seasonal changes of water levels and recharge, 2) organic and inorganic carbon flux from the surface through the porous rock and into a cave, and 3) the role of bacteria in the dissolution of the limestone rock of the Everglades. The MRI study is designed to use existing digital reproductions of intensely-burrowed limestone samples by using Computerized Tomography (CT-scans). A subset of these digital data form the basis for benchtop 3-dimensional replicas produced using prototype printers. MRI imaging is hoped to reveal the velocity vectors of flowing water in the model and allow the evaluation of the advective and dispersive properties of preferred flow zones of the Biscayne aquifer. These data should provide a benchmark for concurrent numerical models using Lattice-Boltzman techniques.

Specific Task Product(s): Three draft journal articles by end of FY08.