Debra Harrington and Haizhi Chen FDEP Groundwater Protection March, 2005 PROTOTYPE FOR SPRING SYSTEM ASSESSMENTS

WATERSHED MANAGEMENT and BASIN ASSESSMENTS IDENTIFY WATER QUALITY ISSUES IWRGRI BASIN ASSESSMENTS SRA Surface Water Ground Water Interaction Spring Water

SPRING SCREENING TOOLS GW/ SW RELATIONAL ASSESSMENT (SRA) Base flow Baseflow that supports aquatic life. Uses surface water criteria and reference values to evaluate ground water flowing from spring vents. The SRA is based on the percent of samples that exceed a threshold related to the environmental conditions necessary to support aquatic life. The SRA is used to assess samples obtained from spring vents, boils, seeps, runs and other surface water bodies associated with springs. Other integrated information such as topography, hydrology, stratigraphy, percent baseflow, and microlanduse are also considered. GROUND WATER RESOURCE INDEX (GRI) Potable water Highest designated use of ground water. Uses ground water standards for contaminant groups such as BIOLOGICAL, NUTRIENTS, ORGANICS, INORGANICS AND SALTWATER INTRUSION. The GRI is based on the percent of wells that exceed a ground water standard and is calculated with and without aquifer stratification. The GRI is used to assess spring samples obtained from conduits, monitor wells and drinking water wells located in the springshed. Important areas are identified that may need further investigation.

GW STANDARDS – SURFACE WATER CRITERIA

SPRINGSPROTECTION ACTION PLAN SPRINGSHEDDELINEATION DATA ANALYSES SPATIAL MAPPING HOT SPOT & LAND USE IDENTIFICATION MONITORING IWR ASSESSMENT WORK GROUPS PUBLIC INVOLVEMENT SPRING ASSESSMENT MODEL

NEW ASSESSMENT TERMS

 Spring Classification System  SPRING GROUP – A collection of individual spring vents and seeps that lie within a discrete spring recharge basin (or springshed (defined as group in Bulletin 66).  SPRING SYSTEM - System is defined as a collection of interconnected springs that have demonstrated hydraulic connections by scientific evaluation (i.e., diving, hydrology, water chemistry, dye tracing).  SPRING CLUSTER – An informal term used to describe a number of springs in the general vicinity of each other. Whether or not the springs are interconnected is unknown.  Springshed Names  Named after particular SPRING if springshed has only one identified spring.  Named as CLUSTER if > one spring that are not defined as a group in Bulletin 66 with unknown hydrologic connections.  Named as GROUP after established “group” of springs defined exclusively in Bulletin 66.  Named as SYSTEM if collection of springs have demonstrated hydrologic connections. SPRINGSHEDS

SPRINGSHED NAMES

 SPRING GROUP – Ichetucknee Group Springshed  SPRING SYSTEM – Gum System Springshed  SPRING CLUSTER – Aripeka Cluster Springshed  INDIVIDUAL SPRING – Buckhorn Springshed SPRINGSHED EXAMPLES

ICHETUCKNEE GROUP SPRINGSHED

GUM SYSTEM SPRINGSHED

ARIPEKA CLUSTER SPRINGSHED

BUCKHORN SPRINGSHED

 Existing Springshed Boundaries Evaluated FGS Repository for all springshed delineations FGS Repository for all springshed delineations Proper methodology established Proper methodology established Uncertainty estimated for various methods Uncertainty estimated for various methods  Hydrologic Studies (dye tracing, natural tracers)  Springshed Wells Identified  GW/SW Geochemistry Evaluated  Potential Spring Systems Recommendations DEP, WMD and FGS Review DEP, WMD and FGS Review SPRING SYSTEM ASSESSMENTS

GROUND WATER SITES  Conduit (grab samples)  Conduit Tubing  Monitor Well SURFACE WATER SITES  Vent  Seep  Boil  Run  Open Drain (siphon, pjole, karst window etc.) SPRING SAMPLE CLASSIFICATION

TYPES OF SAMPLING SITES Low Flow Regimes High Flow Regimes

NEW ASSESSMENT TOOLS

HYDROPORT RETRIEVAL APPLICATION

HYDROPORT STATISTICS REPORT

ICHETUCKNEE SPRING CLUSTER ASSESSMENT STUDY SITE

SPRING RUN DATA AND GROUND WATER STATIONS TYPED AS STREAMS GROUND WATER DATA COMBINED WITH SPRING RUN DATA CAN PRODUCE ERRONEOUS STATISTICS FOR IWR Lower DO medians Lower DO medians Lower or Elevated nitrate Lower or Elevated nitrate

ICHETUCKNEE LAND USE ASSESSMENT

Ground Water Travel Time 7 miles in 6 days DYE TRACE STUDIES

LAKE CITY SPRAYFIELDS AND SINK HOLES

ICHETUCKNEE SPRING CLUSTER BIOLOGICAL ASSESSMENT

BIOLOGICAL  Document specific ecosystem damage  Quantify biological deterioration  Research special projects  Provide results to IWR staff

ICHETUCKNEE SPRING CLUSTER NUTRIENT ASSESSMENT

COMPARE NUTRIENT EMPIRICAL TRENDS IN SPRINGS

COMPARE NUTRIENT EMPIRICAL TRENDS IN GROUND WATER

ICHETUCKNEE SPRING CLUSTER NITRATE TREND ASSESSMENT

COMPARE NITRATES IN SPRINGS TO GROUND WATER

COMPARE NITRATES IN UNCONFINED & CONFINED GROUND WATER

TRIM OUTLIERS AND COMPARE NITRATES IN UNCONFINED & CONFINED GROUND WATER

ICHETUCKNEE SPRING CLUSTER PHOSPHORUS TREND ASSESSMENT

COMPARE PHOSPHORUS IN SPRINGS TO GROUND WATER

COMPARE PHOSPHORUS IN UNCONFINED & CONFINED GROUND WATER (TRIMMED OUTLIERS)

ICHETUCKNEE SPRING CLUSTER AMMONIA TREND ASSESSMENT

COMPARE AMMONIA IN SPRINGS TO GROUND WATER

COMPARE AMMONIA IN UNCONFINED & CONFINED GROUND WATER

COMPARE AMMONIA AND NITRATE EMPIRICAL TRENDS IN GROUND WATER

SUMMARY OF NUTRIENT EMPIRICAL TRENDS IN SPRINGS AND GROUND WATER

 Group I Ichetucknee Head Coffee Cedar Head? Blue Hole?  Group II Mission Spring Devils Eye Grassy Hole Mill Pond Blue Hole? Cedar Head? HYDROLOGIC RELATIONSHIPS

DEVELOP ACTION PLANS  GW Wells Hot Spots – Land Use Develop targeted samplingDevelop targeted sampling Educate public on IssuesEducate public on Issues  Locate Sink Holes – Dye Trace Studies  Sample Sediments Near Vents  Community Involvement DEVELOP ACTION PLANS FOR AREAS IN SPRINGSHED

CONCLUSIONS FOR NUTRIENTS  Nitrate levels are distinctive for springs in the Ichetucknee Cluster. Data should not be compiled to determine overall median values or trends for springs.  Nitrate levels are over the SRA threshold (0.45 mg/L) for Blue Hole, Cedar Head, Ichetucknee Head, and Mission Springs.  Increasing and similar nitrate empirical trends exist for Blue Hole and Ichetucknee Head Springs. Ammonia levels were higher in Blue Hole Spring.  Stable nitrate empirical trends exist for Mission and Mill Pond Springs.  Elevated nitrates exist in the ground water in the springshed at “hot spots”. Nitrates were not correlated to well depths.  Dye studies suggested shallow ground water flow may account for the elevated nitrates found in Ichetucknee Head and Cedar Head Springs. Deeper regional ground water flow may account for the relatively stable trends found in Mission and Mill Pond Springs.  Decreasing ammonia and increasing nitrate empirical trends may be due to mineralization and nitrification and/or land use changes.  Spring run data will be assessed for further investigation.  Empirical trends shown in this prototype will be assessed for statistical significance.

FOR MORE INFORMATION CONTACT Debra Harrington GROUND WATER PROTECTION FLORIDA DEPARTMENT OF ENVIRONMENTAL PROTECTION TALLAHASSEE, FLORIDA