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# 37 Based on the potentiometric surface mapping conducted for this investigation, general flow directions on the karst plain are identified (Figure 25). Werner (2000) gives information on the position of a stagnation point within the Wakulla Springs conduit system. He notes that a separation between north-flowing and south-flowing waters is observable in the main conduit system and that it occurs at distances ranging between 2,100 ft and 7,500 ft south of the spring, depending on flow conditions. Data collected on and near the City of Tallahassee southeast sprayfield (SESF) indicate a southwesterly flow direction into the zone of high conductivity. Such an interpretation is counterintuitive, given the proximity of the sprayfield to the St. Marks River. St. Marks Rise (located near the Leon/Wakulla county line and about half the distance between the SESF and Wakulla Springs) is a significant source of ground water outflow from the Floridan Aquifer. Presumably, the drain effect of the St. Marks Rise should perturb Floridan Aquifer flow directions in southeast Leon County to the southeast. This does not seem to be the case, although the reason for this is not clear. A southwesterly flow direction near the sprayfield, while based in this instance on a limited number of wells is substantiated by previous potentiometric surface mapping at the sprayfield itself (Pruitt et al., 1988 and Berndt, 1990). Additional water level data along the lower St. Marks River would be of value in refining localized flow directions.

# Incorporated Areas Unconfined Semi-Confined U.S. Highways Conduit System Rivers 

# State/County Roads County Boundary Regional Ground Water Flow Direction 

# N GROUND WATER FLOW DIRECTIONS

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# Y # # 

# Newport Wakulla St. Marks Woodville



# Crawfordville LEON CO. WAKULLA CO. R i v 

## e 

# r 

# S t . M a 

# r k 

# W a k u

l l a R i v e 

# r 

# Wakulla Springs St. Marks Rise



# A P A L A C H E E B A Y Y LE

ON CO. W AKULLA CO.



# Y Spring

Creek
Miles 0 5
01-06-011 

# FIGURE 25

# 39 Surface Waters Wakulla Springs and River Wakulla Springs is a major Floridan Aquifer ground water discharge point within the St. Marks and Wakulla rivers basin. The output from the spring is sufficient to form the Wakulla River, which flows southeast about nine miles and discharges into the Gulf of Mexico. Based on USGS data, the period of record median flow from Wakulla Springs is 340 cfs (n=297, mean=397, stdev=266, Figure 26). The lowest observed flow was 25.2 cfs, on June 18, 1931. The largest observed flow, 1,910 cfs, occurred on April 11, 1973. Beneath the spring pool of Wakulla Springs lies an extensive network of large-diameter conduits. The main trunk of the conduit system lies more or less horizontally at depths ranging between 230 ft and 280 ft below sea level . This conduit system runs northeast and south away from the spring, consists of multiple branches, and has been extensively traversed and mapped by divers. Another large conduit system has been mapped by divers starting in the Leon Sinks Geologic Area. This system connects Big Dismal Sink on the north end, with Cheryl Sink, River Sink Group and Turner Sink on the south end (Werner, 2000). It also receives surface water inflow from Fisher Creek. River Sink Group is a collection of three tunnel collapse features that have a significant perennial flow. In each case, water emerges from the ground on the upstream end of the sink, flows along the length of the sink and disappears into the ground on the downstream end. Middle River Sink, which has been measured seven times, has a median discharge of 160 cfs, or about 47 percent of the median discharge of Wakulla Springs. Cave divers have explored several smaller conduit systems on the karst plain including Chip’s Hole, Indian Springs, Sally Ward Spring, McBride’s Slough (Werner, 2000). Though the Big Dismal-Turner Sink and Wakulla Springs systems have not been shown to connect through direct exploration, it is reasonable to presume some degree of interconnection. In the last 25 years, Wakulla Springs has experienced a significant increase in NO 3 

# concentrations (Figure 27). These data were gleaned from USGS and EPA STORET databases and represent a compilation of analyses for (1) NO 3 

# , total (as N); (2) NO 3 

# , dissolved (as N); (3) NO 2 

# +NO 3 

# , total (as N); (4) and NO 2 

# +NO 3 

# , dissolved (as N). These analyses were considered to yield relatively equivalent results for the purpose of illustrating the increase in NO 3 

# experienced at Wakulla Springs. Historically, there has been no measurable NO 2 

# in the ground waters of the study area and, presumably, all detectable NO 3 

# in ground water is dissolved. Based on data from 1971 through 1977, the median NO 3 

# concentration was 0.26 mg-N/L (n=22). Based on data from 1989 through 2000, the median concentration had increased to 0.89 mg-N/L (n=26). Concentrations appear to have peaked in the early 1990s and have declined slightly since. Over similar periods, the NO 3 

# concentration in Middle River Sink increased from a median of 0.06 mg-N/L (n=14) to 0.19 mg-N/L (n=3). The postulated increases are considered accurate, as the data from the 1970s are reported as NO 3 

# -N, total and the data from the 1980s and 1990s are reported as NO 3 

# -N, dissolved. Based on a median flow of 340 cfs (3.04x10 11 

# L/yr), and a median NO 3 

# concentration of 0.89 mg-N/L, the NO 3 

# load discharged from Wakulla Springs is 270,000 kg-N/yr. The difference in the NO 3 

# concentration histories of Wakulla Springs and Middle River Sink is of note. Both show increases with time. River Sink had what are generally considered background concentrations during the 1970s. Currently, River Sink nitrate concentrations are similar to what Wakulla Springs experienced 25 years previously. River Sink lies northwest of Wakulla Springs and, presumably, passes water to the spring from the western edge of the area contributing water to the spring. This water has a much lower nitrate concentration than40Figure 26. Wakulla Springs and Middle River Sink Spring Historic Discharge (data from USGS).04008001200160020001906 1920 1934 1947 1961 1975 1988Date 

# Discharge (cfs)Wakulla SpringsMiddle River Sink41Figure 27. Compilation of NO3-N and NO2+NO3-N Concentration Data for Wakulla Springs and Middle River Sink Spring.00.20.40.60.811.2197119761982198719931998Date 

# Concentration (mg/L)Wakulla SpringsMiddle River Sink

# 42 Wakulla Springs itself. If it is true that River Sink discharges to Wakulla Springs, and if the three recent River Sink nitrate concentration measurements are representative of current conditions, the source of elevated nitrates in Wakulla Springs must lie north and east of the Big Dismal— Turner Sink conduit system. If the flow through River Sink bypasses Wakulla Springs, the same conclusion is true. NO 3 

# concentrations in waters currently discharging from the spring are promoting the growth of undesirable vegetation. Hydrilla and filamentous algae are particularly problematic. According to the FDEP EcoSummary (FDEP, 2000) for Wakulla Springs, “nitrate-nitrite concentrations (ranging from 0.77-0.84 mg/L) at the sampling site were consistently higher than the values found in 90% of Florida streams.” Based on four determinations made during 2000, “the stream condition index (SCI) ranked the site ‘very poor’ once, ‘poor’ twice, and at the lowest end of ‘good’ category once” during 2000. The report further observes that the periphyton community is dominated by taxa that are tolerant of nutrient enriched conditions. Further, they conclude that “the poor macroinvertebrate health was related to the habitat and dissolved oxygen problems caused by Hydrilla , which in turn was due to high nitrate levels” (FDEP, 2000). Katz (2001) performed sampling and isotopic analysis of ground and surface waters from the Woodville Karst Plain, including Wakulla Springs, Fisher Creek, Lost Creek and Munson Slough. Water from most sampled wells and from Wakulla Springs had δ 15 

# N-NO 3 

# values ranging between 6.8 and 8.9 per mil, indicating that their NO 3 

# originates from a blend of organic and inorganic sources. Using 3 

# H/ 3 

# He age-dating techniques, Katz (2001) determined that the average residence time of ground water discharging from Wakulla Springs was 38.7 +/-1.07 years. He also concluded that surface water inflows from sinking streams contributed little NO 3 

# - N to ground waters on the karst plain. St. Marks River The St. Marks River is a second major source of Floridan Aquifer discharge on the Woodville Karst Plain. The St. Marks River originates in the Tallahassee Hills physiographic subdivision. The river headwaters were originally what are now the Lakes Miccosukee and Lafayette drainage basins. Erosion modified the headwater basins to the point where drainage became predominantly internal and the basins closed. Between these basins and the St. Marks River Rise, overland surface flows are intermittent, depending on the amounts of rainfall and overland runoff. In periods of low flow, the St. Marks Rise is the head of the perennial St. Marks River (Rosenau et al., 1977). Based on 42 years of record, the USGS St. Marks River gage (0.65 miles south of the rise) has the following statistics; Q 10 

# —1090 cfs; Q 50 

# —635 cfs; Q 90 

# —408 cfs. Median stage at this station is 8.9 ft, NGVD (Marvin Franklin, personal communication, 2001). Interaction between Wakulla Springs and Up-gradient Surface Water Features Ames Sink Ames Sink lies about 5.5 miles due north of Wakulla Springs and is within the capture zone of the spring. Accordingly, waters that enter Ames Sink eventually discharge from the spring. Ames Sink is on the downstream end of Munson Slough, which conveys surface waters from the lake to the sink. In turn, Lake Munson receives water from the urban drainage system that drains much of the southern part of the City of Tallahassee.

# 43 Conductivity data collected at Ames Sink and flow data collected on Munson Slough above Lake Munson are given in Figure 16. Collection of flow data at Ames Sink was beyond the scope of this investigation. Conductivity and flow data are given for the period 03/99 to 11/00, which includes the very dry summer of 2000. For much of this period, inflows at the sink were minimal to nonexistent. However, the water quality meter used to collect these data was continually submerged. Measured conductivity values ranged from 60 and 250 μ mhos/cm. Typically, conductivities dipped after rainfall events and rose during dry periods. It is possible that the elevated conductivities observed during dry periods reflect re-circulation of Floridan Aquifer waters into the sink in the absence of surface water inflows. Otherwise, conductivity decreases during rainy periods seem to reflect the inflow of stormwater derived from low conductivity rainfall. 1999 Surface Water Conductivity Data During 1999, specific conductivities of water from Wakulla Springs ranged between 275 and 340 μ mhos/cm (Figure 28). These data are typical of Floridan Aquifer conductivities found upgradient of Wakulla Springs. 238 conductance samples collected in Leon County between 1986 and 1999 had a median conductance of 247 μ mhos/cm (mean=241, stdev=62). Elevated conductivity is primarily due to dissolved carbonate from the limestone aquifer. As a function of time, the 1999 Wakulla Springs conductivity data exhibit relatively little variability. 1999 conductivities in the three other surface water features were lower (Figure 28). Fisher Creek is a black-water sinking stream whose watershed lies within the Apalachicola National Forest. During 1999, it had the lowest range of conductivity values, between 30 and 75 μ mhos/cm and exhibited little variability during the year. Fisher Creek conductivities were lowest during dry periods and (curiously) rose following rain events. Lowest observed values for Lost Creek (another black-water sinking stream draining the national forest) were similar to Fisher Creek, in the vicinity of 30 μ mhos/cm. However, during dry periods, conductivities in Lost Creek rose well above those of Fisher Creek, to about 170 μ mhos/cm. This increase is likely attributable to the discharge of Floridan Aquifer water into Lost Creek during low-flow periods. Conductivities in Ames Sink were typically higher than in either Fisher or Lost creeks. 2000 Surface Water Conductivity Data During much of 2000, conductivities in Wakulla Springs were similar (>300 μ mhos/cm) to the previous year (Figure 29). However, September rains were sufficient to perturb the prevailing pattern. During September a total of 19.29 inches of rain fell at the River Sink Station. Of this, 8.31 inches fell during the first week, 1.09 inches fell on September 17 and an additional 9.53 inches were associated with the passage of Tropical Storm Helene on September 22. During September, conductivities in Wakulla Springs declined rather sharply from 310 μ mhos/cm to 250 μ mhos/cm, or by about 20 percent. Within about three weeks of Tropical Storm Helene’s passage through the area, conductivities in the spring rebounded to 320 μ mhos/cm. Middle River Sink had a 2000 conductivity history similar to that of Wakulla Springs. During much of the year values varied through a small range (between 220 to 240 μ mhos/cm). These high values reflect the high proportion of Middle River Sink water originating in the Floridan Aquifer. Rains occurring around the first of September were sufficient to reduce the conductivity by about 20 percent. A precipitous decline followed Tropical Storm Helene (Figure 30). During a six-day period, conductivities fell from 220 μ mhos/cm to 60 μ mhos/cm. For a short period of time, flow through Middle River Sink consisted entirely of surface water, much of it undoubtedly originating from Fisher Creek. The high surface water inflow following rains associated with44Figure 28. 1999 Specific Conductivity and Rainfall versus Time for Fisher Creek, Ames Sink, Lost Creek and Wakulla Springs.050100150200250300350 

# 03/24/99 04/23/99 05/23/99 06/22/99 07/22/99 0

8/21/99 09/ 20/99 10/20 /99 11/19/9 9 12/19/99Date 

# Specific Conductivity (umhos/cm)012345 

# River Sink Station Rainfall (inches/day)RainfallWakulla SpringsLost CreekAmes SinkFisher CreekNo DataNo DataNo DataNo DataCalibration Drift Correction45Figure 29. 2000 Specific Conductivity and Rainfall versus Time for Fisher Creek, Ames Sink, Lost Creek, Middle River Sink andWakulla Springs.050100150200250300350 

# 1/20/00 2/19 /00 3/20 /00 4/19 /0

0 05/19/0 0 6/18 /00 7/18 /00 8 /17 /00 9/16 /00 10/16/00Dates 

# Specific Conductivity (umhos/cm)012345678910 

# River Sink Station Rainfall (inches/day)RainfallWakulla SpringsRiver Sink SpringLost CreekAmes SinkFisher CreekNo DataCalibration Drift CorrectionCalibration Drift46Figure 30. Specific Conductivity and Rainfall versus Time Prior to and Following Tropical Storm Helene, July-November, 2000.050100150200250300350 

# 7 / 1/00

7 / 3

1/

0

0

8 / 3

0 /0

0

9 / 2

9 /0

0

1 0/

2

9/00Date 

# Specific Conductivity (umhos/cm)012345678910 

# River Sink Station Rainfall (inches/day)RainfallWakulla SpringsMiddle River SinkLost CreekAmes SinkFisher CreekCalibration Drift CorrectionCalibration Drift Correction

# 47 Tropical Storm Helene completely overwhelmed the ground water component of Middle River Sink Spring. During this period, waters in Ames Sink, Fisher Creek, Middle River Sink and Lost Creek all had similar conductivities, on the order of 60 μ mhos/cm. By late October, Middle River Sink returned to its typical, Floridan Aquifer dominated flow regime. Wakulla Springs recovered to its typical conductivities over the same period. In Ames sink, Fisher Creek and Lost Creek, conditions during 2000 were similar to 1999. During the prolonged dry period that began around the first of April and ended around mid-July, conductivities in Lost Creek and Ames sink rose well above typical wet period values. For the year Fisher Creek had a fairly narrow range of values, between 30 and 90 μ mhos/cm. Surface Water Temperature Data Figures 31 and 32 give temperature versus time data for Fisher Creek, Ames Sink, Lost Creek, Middle River Sink, Spring Creek and Wakulla Springs for 1999 and 2000. The Wakulla Springstemperature data given in these figures were collected with the S4 meter inside A-tunnel. Meandaily air temperature data from the Tallahassee Airport are also given. For both years, the temperature profile of Wakulla Springs is virtually invariant. During the entire period the only perturbation followed Tropical Storm Helene and that disturbance was slight. Middle River Sink (for which only 2000 data was collected) is only slightly less invariant. The two most significant disturbances occurred in mid-January 2000, during a period of very cold air temperatures, and in September 2000, during periods of high rainfall. In contrast, temperature data for the surface water features closely follow the average daily air temperature, being cooler than Wakulla Springs in winter and warmer in summer. The invariant nature of the temperature data from Wakulla Springs partially substantiates the observation that the spring is deeply imbedded in the regional flow system. Likely, much of the seasonal temperature signal is removed from recharge water by the time it reaches the Floridan Aquifer. There are observations of seasonal temperature fluctuations in individual Floridan Aquifer wells on the order of 2 ° C. Wakulla Springs undoubtedly integrates waters over a wide range of temporal scales. In the process, any remaining seasonal (or other) temperature signals are almost completely removed. Wakulla Springs Velocity and Conductivity Data Specific conductivity and velocity data from Wakulla Springs are given in Figures 33 and 34 for 1999 and 2000. Specific conductivity data were collected from the data logger installed beneath the boat dock (Station #4, above). These data show a generally inverse relationship between conductivity and velocity. Inflows of relatively low conductivity rainfall via sinking streams will undoubtedly mix with and dilute Floridan Aquifer waters discharging from the spring, reducing conductivity in the process. Hurricane Floyd and Tropical Storm Helene passed through the area in September 1999, contributing to a monthly total rainfall of 13.31 inches at the Tallahassee Airport and 19.29 inches at the River Sink Station. In August, A-tunnel velocities were on the order of 8 cm/s and specific conductivities were on the order of 325 μ mhos/cm. In mid-September, tunnel velocities increased to

∼ 17 cm/s. Concurrently, the conductivity declined to ∼ 300 μ mhos/cm. The observed increase in velocity from 8 cm/s to 17 cm/s should represent roughly a doubling of the spring discharge. Assuming that 325 μ mhos/cm represents 100 percent Floridan Aquifer water and assuming a surface water conductivity of about 40 μ mhos/cm, a blending ratio of 93 percent Floridan Aquifer water to 7 percent surface water is required to reduce the conductivity from 325 to 300 μ mhos/cm. This mixing ratio is independent of spring flow.48Figure 31. 1999 Temperature and Rainfall versus Time for Fisher Creek, Ames Sink, Lost Creek and Wakulla Springs.5.0010.0015.0020.0025.0030.0035.00 

# 3/24/99

4/7/99 4/2 1/99 5/5/99 5/19/99

6/2/99 6/1 6/99 6/30/99 7/14/99 7/28/99 8/1 1/99 8/25/99

9/8

/99 9/22/99 10

/6/99 10/20 /99 11/3/99 11/17/99

12

/1/99 12/15 /99 1 2/29/99Date 

# Temperature (degrees C)012345 

# River Sink Station Rainfall (inches/ day)RainfallWakulla SpringsSpring CreekLost CreekAmes SinkFisher CreekAir TemperatureNo Data No Data49Figure 32. 2000 Temperature and Rainfall versus Time for Fisher Creek, Ames Sink, Lost Creek, Middle River Sink and WakullaSprings.5.0010.0015.0020.0025.0030.0035.00 

# 1/1

/00 1/3 1/00 3/1/00 3/3 1/00 4/3 0/00 5/3 0/00 6/

2

9/00 7/29/00 8/2 8 /00 9/2 7/00 10/27/00Date 

# Temperature (degrees C)012345678910 

# River Sink Station Rainfall (inches/ day)RainfallWakulla SpringsMiddle River SinkLost CreekAmes SinkFisher CreekAir Temperature50Figure 33. 1999 Wakulla Springs Velocity versus Specific Conductivity.051015202530 

# 0 6/18/99 07/

03/99 07/18/ 99 08/02/9 9 08/17/99 09/01/99 09/16/99 10/01/99 10/16/99 10/31/99 11

/15/99 11/

30/99 12/15/ 99 12/30/99Date 

# Velocity (cm/s)260270280290300310320330 

# Conductivity (umhos/cm)Velocity (cm/s)Conductivity (umhos/cm)Calibration Drift Correction51Figure 34. 2000 Wakulla Springs Velocity versus Specific Conductivity.0102030405060 

# 01

/01/00 01

/16/00 01

/31/00 02

/15/

00 03

/01

/00 03

/ 16/00 0 3 /31/00 04

/15/00 04

/30/00 05

/15/00 05

/30/0 0 06

/14

/00 06

/ 29/00 07/14/00 07

/29/00 08

/13/00 08

/28/00 09

/12/0 0 09

/27

/00 10

/1

2/00 10/27/00 1 1 /11/00Date 

# Velocity (cm/s)240250260270280290300310320330340 

# Conductivity (umhos/cm)Velocity (cm/s)Conductivity (umhos/cm)Calibration Drift Correction

# 52 The addition of surface water inflow from sinking streams is not sufficient to double discharge from the spring. Rather, the increase in flow is mostly accounted for by additional discharge from the Floridan Aquifer. The increase in Floridan Aquifer discharge through the spring results from a slight increase in Floridan Aquifer water levels attributable to short-term, relatively intense rainfall events. Given the extremely high hydraulic conductivity of the Floridan Aquifer, it is not surprising that small increases in hydraulic head result in a significant increase in discharge.

# 53 WATER QUALITY IN THE FLORIDAN AQUIFER Historic Nitrate Concentrations Two previous studies (1986 and 1997) by the Department of Health (DOH) provide insight into historic NO 3 

# concentrations in the Floridan Aquifer. Wells used in these studies are described in Table 5. One study performed in 1986 concentrated on Leon County. When these data were examined, it appeared that they had significant quality assurance problems. For this reason NO 3 

# data obtained by the DOH in 1986 were not mapped. The data are included in time series representations for several wells. The second DOH study, performed in 1997, focused on Wakulla County (Figures 35 and 36). Data from the FDEP GWIS data set, USGS databases and the City of Tallahassee were combined with the DOH data to produce data sets as complete as possible for 1997. The data represent a compilation of analyses for (1) NO 3 

# , total (as N); (2) NO 3 

# , dissolved (as N); (3) NO 2 

# +NO 3 

# , total (as N); (4) and NO 2 

# +NO 3 

# , dissolved (as N). These analyses were considered to yield relatively equivalent results for the purpose of illustrating NO 3 

# concentrations in the Floridan Aquifer. Historically, there has been no measurable NO 2 

# in the ground waters of the study area and, presumptively, all detectable NO 3 

# in ground water is dissolved. Results of the 1997 study show that NO 3 

# concentrations are quite variable over the study area. Most results from the semi-confined and unconfined areas are above detection limits, reflecting a widespread distribution of NO 3 

# from anthropogenic sources. There is a scattering of values below detection limits (BDLs) in the unconfined portions of Leon and Wakulla counties. BDLs are even more prevalent in Wakulla County where the Floridan Aquifer is under confined conditions (western half of county). This reflects the relatively low population density in this area and the greater degree of aquifer confinement. Project-specific Ground and Surface Water Sampling Six surface water sites and 41 Floridan Aquifer wells were sampling as part of the project (Figure 9, Appendix A, Table A3). A complete list of sampling results is presented in Table 7. Six of the sampled wells were constructed for the project. They, along with Middle River Sink and Wakulla Springs were sampled twice more—during low-flow and high-flow conditions—for various isotopes. Analytical results from these data collection efforts are described in greater detail in Katz et al. (in preparation). NO 2 

# +NO 3 

# The overall distribution of NO 2 

# +NO 3 

# -N (Figure 37) is consistent with the historical data—few BDL concentrations and a variable distribution on the karst plain, with concentrations below detection limits in the undeveloped eastern portion of Wakulla County and along the coast. Concentrations in ground water ranged from below the detection limit of 0.020 mg-N/L to 7.3 mg-N/L. The primary drinking water standard for nitrate is 10 mg/L. In surface water inflows (Lost Creek, Fisher Creek and Munson Slough) NO 2 

# +NO 3 

# -N concentrations are below detection limits. In surface water outflows (Wakulla Springs, Sally Ward Spring, Middle River Sink Spring, and McBride Slough) NO 2 

# +NO 3 

# -N concentrations ranged from 0.19 mg-N/L to 1.0 mg-N/L. The six wells constructed for the project, Middle River Sink and Wakulla Springs were sampled for nitrogen isotopes to obtain a δ 15 

# N-NO 3 

# value. δ 15 

# N-NO 3 

# values are helpful in distinguishing

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( X ( X ( X ( X ( X ( X

( X ( X

( X ( X ( X
( X

( X ( X ( X ( X ( X ( X

( X 

# ø ÷ 26

7 

# # 

# ( / 319 

# . - , 10 

# ( / 90 

# " !

20 

# " !

61 

# % g 365 

# ( / 319 

# ø ÷ 267 

# ( / 98 

# ( / 319



# ø ÷ 363 

# Quincy



# Newport Wakulla

Sopchoppy Midway Havana

St. Marks 

# Wildlife Refuge St. Marks National Apalachicola National Forest GADSDEN CO.SRWMDNWFWMD JEFFERSON CO. 

# Lake Iamonia Lake Miccosukee Lake Lake Lafayette



# A P A L A C H E E B A Y R

i v e r R



# i v 

# e r S t . M a r 

### k 

## s 

# O

c h l o c k o n e e 

# Jackson

Crawfordville 

# Tallahassee
Woodville W

a k u



# l l 

# a



# Panacea 

# L

a 

# k e 

# T



# a

l 

# q u

i n



# #

FRANKLIN CO. LIBERTY CO. LEON CO. WAKULLA CO. Lake Munson R i v 

### e 

## r



# Wakulla Springs

231 251 276 280 313 326 334 338 339

344 351 356 381 402

391 399 412 507 527 547 607 653 654 658 698

728 746 769 801 802 831 998

713

325 977

648 978 5851

1020 1233 1542 1569 2043 2106 2333 2375 2782 2863 2957 3181 3691

3946

7796 1103 1663

278 330 363 354 544 564 613 663 674 702 701 641

343 372 635 1165 1289 1056 1166 1156 1164 1240 1290 1511 2196 2377 2573 2621 2692 2707 2708 2990 3013 3028 3108 3379 3522

7223

7268

7269 7270 7285 2742

7832 7833 1512

710 

# 717 

# GEORGIA

1007 3021



# WAKULLA CO. LEON CO.

TAYLOR CO. Gretna

2706 

# LOCATION OF WELLS USED IN 1997 SAMPLING EVENT



# N Control Well Location ( X 

# U.S. Highways State/County Roads Major Lakes Rivers Incorporated Areas Public Lands 

# 0 51 0 

# Miles 01-06-013 

# FIGURE 35

# # S

# S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S

# S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S

# S # S # S # S # S

# S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S # S

# S # S

# S # S # S # S # S # S

# S # S # S

# S # S # S

# S

# S # S # S # S # S # S # S 

# Y 

# ø ÷ 26

7 

# # 

# ( / 319 

# . - , 10 

# ( / 90 

# " ! 20 

# " ! 61 

# % g 36

5 

# ( / 319 

# ø ÷ 26

7 

# ( / 98 

# ø ÷ 363 

# 0.4 0.06

0.26 1.20 0.43 0.32 0.07 0.14 0.22 0.69 0.58 0.84 0.26 0.58 0.55 0.38 1.60 1.20 1.30 0.68 0.71 0.22 0.48 5.29 6.59 0.02 4.63 0.71 6.26 0.89 0.47 0.47 0.50 0.50 0.68 0.23 0.28 0.30 0.32 0.37 0.57 0.30 0.11 0.44 0.40 0.05 0.41 0.23 0.50 0.22 0.27 0.21 0.13

0.27 1.70 5.78 3.65

5.23 5.49 0.27

0.89 0.51 1.01 5.87

0.19 3.10 0.18 1.04

12.00

BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.02) BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.02) BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.05) BDL (0.01)

BDL (0.05) BDL (0.02)

BDL (0.02) BDL (0.02) BDL (0.02)

0.74 5.87 0.32 0.29
8.35 13.7

BDL (0.05) Quincy



# Newport Wakulla

Sopchoppy Midway

St. Marks 

# Wildlife Refuge St. Marks National Apalachicola National

Forest GADSDEN CO. 

# Lake Lake Lafayette



# A P A L A C H E E B A Y R i v e r R



# i v 

# e r S t . M a 

### r 

## k 

# s 

# O

c h l o c k o n e e 

# Jackson

Crawfordville 

# Tallahassee
Woodville W

a k u



# l l 

# a



# Panacea 

# L

a 

# k

e 

# T



# a

l 

# qu i n

WAKULLA CO. 

# #

FRANKLIN CO. LIBERTY CO. LEON CO. WAKULLA CO. Lake Munson 

# WAKULLA C O . LEON CO. R i 

### v 

## e 

# r



# Wakulla Springs



# N Sampling Locations (Concentration mg-N/L) # S 

# U.S. Highways State/County Roads Rivers County Boundary Incorporated Areas Public Lands Major Lakes 

# 0 51 0 Miles BDL-Below Detection Limit

(Individual Detection Limit) 

# COMPILATION OF NO -N AND NO +NO -N CONCENTRATIONS IN THE FLORIDAN AQUIFER, 1997 3 3 2

01-06-014 

# FIGURE 36

# NO + NO - N CONCENTRATIONS, 1999 - 2000 2 3

% %% % %% % %% % % % %% % % % % % % % %%% % % % % %% % % % %% % % % % % % % % % % % %% % % % % % % %% % % %% % % % % % % %% % % %% %% % % % % % %% % %% % %%

% % % %% % % %%%% % % % % % % % % % % % % % % %% %%% % % % % %% % %% % % % % % % % % %% % % %% % %% % %% % % % % % % % %

% %% % % % % % % % % % % % %
% % %% % % % % % % % % % %% % % % % % % % % % % % %%
% % % %% % % %% % % %% % % % %% % %% % % %% % % % %%% % % % %% %% %% %% % % % %% %% % % % % % % %% % %% %%% % % % % % % % % %% % % %% % % % % % % % %% % % % % % % %% %% %% %% % % % %% %% % % % % % % %% % %% %%% % % % % % % %% % % % %%% % % %% %

% % %% % % % %

% % %% %% % % % % % % % % %% % % %

% %% %% %% % %%% %% % % % %%% %% % % % % % %% %% % % % % % % % %%% % % % % % % % %% % %% % % % % % %% % %% % %% % % % % % % % %% % % % %%% % % %% % % % % % %% % %%% % %% %% % % % % % % % %% % % % % %% % % %% % % % % %%% % % % % % % % % % % % % % % 

# Y Y # S

# S # S # S # S # S # S # S # S # S # S # S # S 

# $ T # S # S # S # S # S # S # S # S # S

# S # S # S

# S # S # S # S # S # S 

# $ T

# S # S # S # S 

# $ T # S # S # S



# $ T $ T $ T $ T


# #

R i 

### v 

## e 

# r



# LEON CO. WAKULLA CO. WAKULLA CO. LEON CO.



# FRANKLIN CO. Panacea Woodville Crawfordville

O

c h l o c k o n e e

S t . M a 

### r 

## k 

# s 

# R i v e r 

# GADSDEN CO.



# A palachicola N ational Forest Marks St. Midway

Sopchoppy Wakulla Newport W

a k u



# l l 

# a 

# Tallahassee

R 

# i v 

# e r 

# ø ÷ 363 

# ( / 98 

# ø ÷ 26

7 

# ( / 319 

# % g 36

5 

# " ! 61 

# ø ÷ 26

7



# St. Marks National Wildlife RefugeNWFWMDSRWMD JEFFERSON CO. 

# ( / 319 

# ( / 98 

# ( / 90 

# . - , 10 

# ( / 90 

# ( / 2 7

# L

a k

e T

a

l 

# q u



# i n



# A P A L A C H E E B A Y Lake Lafayette Lake Jackson

1.60

0.24 0.04 0.52 0.05 0.34

7.30 0.97 0.83 0.24 0.31 0.68 0.76 1.20 0.63 0.70 0.58

0.34 1.40 0.14
0.66 0.17 0.20

4.00 0.18 1.00 0.59 0.07 0.38

0.58

BDL (0.02) BDL (0.02) BDL (0.02) BDL (0.02) BDL (0.02)

BDL (0.02) BDL (0.02) BDL (0.02) BDL (0.02) BDL (0.02) BDL (0.02) BDL (0.02)

BDL (0.02) BDL (0.02) BDL (0.02) BDL (0.02) BDL (0.02)

BDL (0.02) 

# Wakulla Springs L. Miccosuk ee



# St. Marks

Rise 

# Lake Munson



# Y Spring

Creek 

# N BDL - Below Detection Limit (Individual Detection Limit) 

# 0 51 0 Miles (Concentration mg-N/L) SW Sampling Location $ T # S 

# GW Sampling Location Springs 

# Y District Boundary Lakes Incorporated Areas Public Lands County Boundary U.S. Highways Rivers Conduit System State/County Roads 01-06-016 

# FIGURE 37

# 57 between organic and inorganic sources of nitrate. Low values (0 to 3 per mil) indicate an inorganic nitrate source such as artificial fertilizer. Higher values (10 to 20 per mil) indicate an organic nitrate source such as septic tanks, waste disposal or manure spreading (Katz et al., 1999). With four of six wells constructed for the project having BDL NO 3 

# -N concentrations, four additional wells from the sampling network with elevated NO 3 

# -N concentrations were selected to replace them. Values for δ 15 

# N-NO 3 

# are shown below: Table 4. δ 15 

# N-NO 3 

# Values. Site name (NWF ID) δ 15 

# N-NO 3 

# (per mil) Wakulla Springs (749) 6.3 Middle River Sink (7757) 4.5 Nitrate #1 (7492) 4.6 Nitrate #5 (7498) 7.4 Claycomb (6493) 2.6 Johnson (674) 0.6 Garcia (663) 3.1 Blackstead (641) 7.6 Wakulla Springs data are consistent with previous sampling results (Katz, 2001) and indicate a mixture of nitrogen sources. Middle River Sink, Nitrate #1 and Garcia also indicate a mixing of sources, tending toward the inorganic. Claycomb and Johnson, both adjacent to agricultural land uses, have a strong inorganic source indication. Nitrate #5 and Blackstead indicate a mixture of sources. Previous δ 15 

# N analysis in the study area was perfomed by the USGS (Berndt, 1990) at the SESF. Sampling for δ 15 

# N analyses in Floridan and surficial aquifer was conducted during January 1988 and the reported median δ 15 

# N ratio was 7.2 per mil (n=13, mean=8.1, stdev=2.3, range=5.9 to 12.4). From this data, Berndt concluded that the application of inorganic fertilizer at the SESF was influencing N isotopic ratios in ground waters at the site. Dissolved Organic Carbon Dissolved organic carbon (DOC) values ranged from below a detection limit of 0.1 mg-C/L to 31.0 mg-C/L (Figure 38). Highest levels occurred in surface water inflows (Fisher Creek, Munson Slough and Lost Creek). Concentrations in ground water were generally low. However, some wells had concentrations sufficiently elevated to indicate a possible influence from surface water. Dissolved Oxygen Dissolved oxygen (DO) was determined as a field parameter at the time laboratory samples were collected. DO values ranged from zero mg-O/L (in one of the wells constructed for the project) to 11.9 mg-O/L (Figure 39). Surface water and ground water concentrations are scattered throughout this range, although the lowest values (<1.0 mg/L) are all from ground waters. pH Values for pH were measured in the field at the time of sample collection. Values ranged from 3.5 to 8.5 standard units (Figure 40). Surface water inflow sites (Fisher Creek, Munson Slough and Lost Creek) generally had low pH, ranging from 3.5 to 6.4 standard units (su). One ground water site (Seminole Golf Course) had a pH indicative of surface water influence (5.3 su).

# DISSOLVED ORGANIC CARBON CONCENTRATIONS, 1999 - 2000

% %% % %% % %% % % % %% % % % % % % % %%% % % % % %% % % % %% % % % % % % % % % % % %% % % % % % % %% % % %% % % % % % % %% % % %% %% % % % % % %% % %% % %%

% % % %% % % %%%% % % % % % % % % % % % % % % %% %%% % % % % %% % %% % % % % % % % % %% % % %% % %% % %% % % % % % % % %

% %% % % % % % % % % % % % %
% % %% % % % % % % % % % %% % % % % % % % % % % % %%
% % % %% % % %% % % %% % % % %% % %% % % %% % % % %%% % % % %% %% %% %% % % % %% %% % % % % % % %% % %% %%% % % % % % % % % %% % % %% % % % % % % % %% % % % % % % %% %% %% %% % % % %% %% % % % % % % %% % %% %%% % % % % % % %% % % % %%% % % %% %

% % %% % % % %

% % %% %% % % % % % % % % %% % % %

% %% %% %% % %%% %% % % % %%% %% % % % % % %% %% % % % % % % % %%% % % % % % % % %% % %% % % % % % %% % %% % %% % % % % % % % %% % % % %%% % % %% % % % % % %% % %%% % %% %% % % % % % % % %% % % % % %% % % %% % % % % %%% % % % % % % % % % % % % % % 

# Y # S

# S # S # S # S # S # S # S # S # S # S # S # S 

# $ T # S # S # S # S # S # S # S # S # S

# S # S # S

# S # S # S # S # S # S 

# $ T

# S # S # S # S 

# $ T # S # S # S



# $ T $ T $ T $ T 

# Y # R i 

### v 

## e 

# r



# LEON CO. WAKULLA CO. WAKULLA CO. LEON CO.



# FRANKLIN CO. Panacea Woodville Crawfordville

O

c h l o c k o n e e

S t . M a 

### r 

## k 

# s 

# R i v e r 

# GADSDEN CO.



# A palachicola N ational Forest Marks St. Midway

Sopchoppy Wakulla Newport W

a k u



# l l 

# a 

# Tallahassee

R 

# i v 

# e r 

# ø ÷ 363 

# ( / 98 

# ø ÷ 26

7 

# ( / 319 

# % g 36

5 

# " ! 61 

# ø ÷ 26

7



# B A Y A P A L A C H E E St. Marks National Wildlife RefugeNWFWMDSRWMD JEFFERSON CO. 

# ( / 319 

# ( / 98 

# ( / 90 

# . - , 10 

# ( / 90 

# ( / 2 7

# 0.2

9.0 0.5 1.5 0.6 7.5 0.2 0.5 0.3

0.3 0.6 5.8 0.2

0.2 0.5

1.9 1.8 1.0 1.6 0.6 0.7 2.6

0.5 1.6 0.5 0.3 0.1 1.5

31.0 BDL(0.10) BDL(0.10) BDL(0.10) 24.0 BDL(0.10) BDL(0.10) 6.6

BDL(0.10) BDL(0.10) BDL(0.10) BDL(0.10) BDL(0.10) BDL(0.10)

0.5 BDL(0.10)

0.1 0.2
0.20 

# Wakulla Springs BDL(0.10) L. Miccosuk ee 

# L

a k e T

a

l qu

i n



# St. Marks Rise 

# Lake Lafayette Lake Jackson

Lake Munson



# Y Spring

Creek 

# 0 51 0 Miles 

# N BDL - Below Detection Limit (Individual Detection Limit) (Concentration mg-C/L) SW Sampling Location $ T # S 

# GW Sampling Location Springs 

# Y District Boundary County Boundary U.S. Highways Rivers Conduit System State/County Roads Lakes Incorporated Areas Public Lands 01-06-017 

# FIGURE 38