U.S. Department of the InteriorU.S. Geological Survey

Nitrate and Groundwater Flow to Springs in the Upper Floridan aquifer, Lower ACF

—Chipola Basin

by Christy Crandall

Objectives of Study—2007 through 20091) To quantify

• groundwater travel times

• areas contributing recharge

• hydrologic and geochemical processes occurring along flowpaths

2) Test 3 nitrogen management scenarios from 2002 through 2050 in areas contributing recharge to Jackson Blue, Baltzell Group, and Sandbag Springs.• Cessation of nitrogen input after 2001

• 4 percent decline per year of nitrogen input

• Maintain nitrogen input at 2001 levels

Study Area

Study Area

Lower ACF Basin

Elevation

Streams

Physiographic provinves

Floridan AquiferSystem

Named Springs

Mapped Closed-basin depressions

Confinement Status

Crack-in-the-woods Spring in the Chipola River Bed

Approximately 50 % of the Land Use is Agriculture

ACFB agricultural land use study -- trend data for nitrate

Regional Model

Sub-Models And Selected Groundwater sites

Results

STATION ID STATION NAME

WELL

DEPTH DO DOC FE NO3

as N N15/N14

305725085094102 MALONE No. 02115 6.6 <0.3 <6 6.43 3.46

305219085144901 JAPSTER00137 8.5 0.6 <6 6.39 3.85

304948085140501 BALTZELL SPRING GROUP -- 9.5 <0.2 <6 3.74 3.13

304746085223201 CITY OF COTTONDALE NO.3,128 3.0 0.6 30 0.99 7.36

304707085153301 HUTTON70 8.0 0.4 <6 0.37 7.62

304718085132000 SAND BAG SPRING -- 5.4 <0.3 <6 0.49 7.01

305137085060301 NWFWMD 8065 8.5 <0.4 <6 3.81 2.00

305025085082101 NWFWMD 8585 7.0 <0.3 <6 3.27 2.23

02358795 JACKSON BLUE SPRING  -- 10. <0.3 <6 3.24 2.31

Water Quality Results

AGE OF RECHARGE WATER AND PARTICLE TRACKING

RESULTS

Table __. Summary of apparent ages (averages) from Piston Flow model.

CFC-11 CFC-12 CFC-113 SF6 %youngc113/c11 ratio

Jackson Blue Modern Contam. 21 16Hutton Contam. Contam. Contam. 17Sandbag 12 Contam. 22 19Cottondale 32 Contam. 25 30 24Baltzell Contam. Contam. Contam. 16Baxter 25 19 20 16 82 15Hwy69-VISA 23 18 20 14 65 19JAPST001 24 18 20 21 73 18Malone #2 Contam. 15 22 13

Preliminary Age Dating Results

pART

Particle Age and Area Contributing Recharge to Springs

StatisticSandbag Jackson Baltzell

Maximum 50.69 78.23 45.65

Minimum 7.91 0.01 0.12

Average 21.11 9.82 17.54

Median 20.44 8.49 14.05

Standard Deviation 10.66 6.46 11.49

NITRATE IN THE UPPER FLORIDAN AQUIFER AND

SCENARIOS

Uncertainties of Fertilizer Data

Locations of use?

K

Jackson County, Florida, 1945 to 2001

Nitr

ate-

N in

mg/

L

Estimated changes in nitrate concentrations in Jackson Blue, Baltzell Group, and Sandbag Spring from 2002 through 2050 with 3 different management scenarios

• Cessation of nitrogen input after 2001

• 4 percent decline per year of nitrogen input

• Maintain nitrogen input at 2001 levels

Estimated changes in nitrate concentrations in Jackson Blue Spring from 2002 through 2050 with 3 different management scenarios

Estimated changes in nitrate concentrations in Baltzell Spring Group from 2002 through 2050 with 3 different management scenarios

Estimated changes in nitrate concentrations in Sandbag Spring from 2002 through 2050 with 3 different management scenarios

Future of Study

Future Directions--Large Objectives

Develop linked groundwater/surface water model to calculate daily stage, stream flux, and head, as a function of pumpage, rainfall, upstream conditions, climate events, and dam releases through 2050

Future Directions—my tasks Convert Current Model to transient flow model

Use more sophisticated unsaturated flow and streamflow routing to account for aquifer- stream interaction, evaporation and recharge in the surficial aquifer/residium.

Calibrate transient model for 1978 to 2008 recharge, stream and spring flow and pumpage conditions.