L-31N Seepage Management Field Test

Transcription

1 Miami-Dade Limestone Products Association N.W. 118 th Avenue Miami, FL L-31N Seepage Management Field Test The Performance of a Partially Penetrating Seepage Barrier along the L-31N Canal July 2011 Prepared on behalf of the Miami-Dade Limestone Products Association by MacVicar, Federico & Lamb, Inc. West Palm Beach, Florida

2 L-31N Seepage Management Field Test Lake Belt Seepage Management Demonstration Project Background Recent investigations by the U.S. Geological Survey and the South Florida Water Management District have documented distinct layering within the Biscayne Aquifer and identified preferential flow zones within specific layers in the area of the L-31N Canal, which defines the northern portion of the eastern boundary of Everglades National Park (ENP). One of the high flow layers is the Miami limestone, which makes up the top 5 to 10 feet of the aquifer in the vicinity of the canal. It is this top layer of porous rock that appears to serve as a conduit allowing water from the wetlands within ENP to flow into the L-31N Canal. The proposed field test of a partially penetrating seepage barrier was described in an earlier report produced in February The proposal was presented to the Lake Belt Mitigation Committee, as well as technical staff at Everglades National Park and the South Florida Water Management District. The SFWMD issued a right of way permit for the construction of the test project, including monitoring wells, on the berm between the L-31N Levee and Canal at a location one mile south of Tamiami Trail. The goal of the test was to document the performance a of partially penetrating flow barrier in reducing groundwater interception by the canal. The test consisted of constructing a cement-bentonite flow barrier in a narrow trench extending through the Miami limestone layer of the aquifer just west of the L-31N Canal. The test barrier was located with its midpoint adjacent to the northern cluster of monitoring wells installed as part of the L-31N Seepage Management Pilot Project. (Figure 1) Site Layout Figure 2 shows the geologic cross section at the monitoring well cluster from USGS Scientific Investigations Report (Cunningham, et al). The Biscayne Aquifer in this area is generally considered to consist of the Miami oolite in the upper section and the Ft. Thompson formation below. Below the Ft. Thompson is the lower permeability Tamiami Formation, which is not considered to be part of the Biscayne Aquifer. At this location, the Miami oolite, shown as the uppermost light blue layer in Figure 2, is 6 to 8 feet thick and is classified as a conduit flow zone with very high permeability. The salmon colored layer below the Miami oolite is classified as a leaky, low permeability layer in the USGS report. A two foot thick layer of fine sediment has accumulated on the bottom of the canal impeding hydraulic interaction between the canal and the aquifer directly below the canal. It is likely that the Miami oolite layer is a significant source of groundwater flow from ENP to the L-31N Canal. This test was designed to help determine the extent to which a seepage barrier through the top layer of the aquifer would reduce the unwanted diversion of water from ENP to the adjacent canal. A one thousand linear feet long cementbentonite seepage barrier, 28 inches wide and 18 feet deep, was constructed in the canal right-of- way between the L-31N Canal and Levee. July

3 L-31N Seepage Management Field Test Figure 1. Project location. July

4 L-31N Seepage Management Field Test Figure 2. Schematic diagram of test area cross-section. Well core and layer coloring are taken from USGS Scientific Investigations Report (Cunningham, et al, 2006). The Miami oolite (top blue layer) is categorized as a conduit flow zone in that report. Monitoring Well Instrumentation The wells shown in Figure 3 were equipped with instruments to allow the continuous recording of water level, flow direction, flow velocity and water temperature. It was expected that by constructing the barrier with the midpoint adjacent to the monitoring wells, the impact of the barrier on groundwater flow would be detected. Changes in both the velocity and direction on flow in the shallow groundwater well were predicted to occur. However, the data produced by the instrumentation to detect velocity and direction proved difficult to interpret in the heterogeneous, complex flow paths through the rock in that location. The most informative data seemed to be the simple water level readings collected in each well, with the flow direction in the wells near the end of the test wall also proving useful. Figure 3. Location of seepage barrier within the L-31N Canal right-of-way and sketch of monitoring well placement. July

5 L-31N Seepage Management Field Test Monitoring Results For the purpose of providing an initial look at the impacts of installing the barrier, the data set was divided into pre-and post-construction periods of 30 days each. With the high transmissivity of the aquifer, any changes to the groundwater flow as a result of the test barrier were expected to be subtle, and difficult to detect. The plot of the stage data in Figure 4 shows a greater stage difference between the canal and the recording wells on the west side of the barrier after the slurry wall was constructed. However it is impossible to tell whether the difference is caused by the barrier or simply by changing conditions in the area. The L-31N Canal is actively managed during the wet season to keep the stage within a narrow range, while the wet season rainfall tends to increase the stage in the Park. Both of these conditions are noticeable from the data collected after the wall was installed. 8.0 Water Level Data Before and After Barrier Installation Center Well D Center Well C Well 425 Well 475 L-31N Stage ENP Stage Stage Barrier Installed 5.5 7/4 7/18 8/1 8/15 8/29 9/12 9/26 10/10 Figure 4. Water level data from monitoring wells, L-31N Canal and adjacent wetland in ENP. To try to isolate the effect of the test barrier, plots were developed of the stage difference between the wells just west of the barrier and the canal for 30-day periods just prior to and after the construction of the barrier. Figure 5 is the plot of the stage difference between the shallow groundwater well about 25 feet west of the barrier and the canal stage about 30 feet to the east. The plot shows an increase in the stage difference after construction and also a decrease in the r-squared value of the relationship between the groundwater and the canal. Both of these would indicate that the wall had the desired effect of separating the canal from the shallow groundwater. However, a similar plot, Figure 6, for a station about a mile to the south exhibits similar characteristics, and this location could not be affected by the test barrier. With the extremely high transmissivity July

6 L-31N Seepage Management Field Test of the aquifer in this location, a significant impact on the stage either in the surface water or the shallow groundwater was not expected. The changes seen in these data from before and after the construction are more likely a response to the changing conditions than to the impact of the barrier itself. That is not to say that the barrier would not be effective at reducing groundwater flow to the canal, only that the stage data alone do not provide definitive evidence of the success or failure of the concept. Figure 5. Well D is the shallow groundwater stage just west of the midpoint of the slurry wall. The L-31N Canal is just east of the wall. The difference in the relationship between the two data groups is a function of the changing hydrologic conditions as well as the construction of the wall Pre and Post Slurry Wall Construction: NESS20-29 Site 6.50 R² = Enp Stage (NESS20-29) R² = prior to construction after construction L-31N Canal Stage Figure 6. Site NESS20-29 is a groundwater stage about 500 feet west of the L-31N Canal and about a mile south of the test wall. The presence of the test wall has no effect on this site. July

7 L-31N Seepage Management Field Test In addition to the ground and surface water stage data, information on groundwater flow velocity and direction was also collected. The flow velocity and direction data is difficult to interpret and no definitive conclusions regarding the performance of the barrier could be derived from the data set. Barrier installed Figure 7. Data collected from the velocity sensor before and after wall construction. July

8 L-31N Seepage Management Field Test Additional Testing Due to the uncertainties in determining the effectiveness of the seepage barrier, the following additional testing/evaluations were performed during 2010 and 2011: Groundwater stage analysis Groundwater temperature changes Groundwater tracer test Canal flow measurement analysis Barrier physical integrity testing Groundwater stage measurements In preparation for the tracer test, a total of 40 shallow and deep monitoring wells were installed in the vicinity of the seepage barrier and at a control site (without the seepage barrier) approximately 500 feet to the south (Figure 8). The well locations and depths (with the exception of four shallow wells at the ends of the barrier) were identical. Figure 8. Tracer test monitoring locations. The top of the low permeability freshwater limestone layer (Q4 marker bed) between the Miami oolite and the Ft. Thompson formation was identified at a depth of approximately 14 feet below land surface at the site. The shallow monitoring wells were installed both east and west of the barrier and completed in the Miami oolite above the Q4 layer (with a total depth of 11 feet and well screen between 7 and 11 feet). The deep monitoring wells were installed only west of the barrier and completed in the Ft. Thompson formation below the Q4 layer (with a total depth of 40 feet and well screen between 20 and 40 feet). July

9 L-31N Seepage Management Field Test Groundwater stage data were collected periodically in the 6 shallow upgradient tracer test dye introduction wells and the associated downgradient shallow and deep monitoring wells (Appendix 1). In addition, stage data in the USGS monitoring well (G-3576) located one mile west of the barrier and in the L-31N Canal (AVM-1) were obtained from the USGS website. At the southern monitoring site (with no barrier), the flow at the project site was from the west (from ENP to the L-31N Canal) during the west season and from both the west (ENP) and east (canal) during the dry season (Figure 9). Figure 9. Average water levels at the southern control site without the barrier. The groundwater stage in the vicinity of the barrier also varied seasonally (Figure 10). The top graph shows that the average groundwater stages in the deep and shallow monitoring wells at the control site were essentially identical, suggesting minimal flow between the Miami oolite and the Ft. Thompson formation. However during the wet season, the deep water levels at the barrier site are higher, suggesting some upward flow due to the installation of the barrier. Similarly, the bottom graph shows that the average water level in the shallow west and east wells at the control site are similar (with a slight positive gradient towards the canal during the wet season). The wells are approximately 20 feet apart and the slight gradient reflects the overall westerly flow from ENP to the L- 31N Canal. During the wet season, the water levels in the west wells at the barrier site are noticeably higher than the east wells, suggesting that the barrier is interrupting the shallow flow resulting in higher upgradient water levels. July

10 L-31N Seepage Management Field Test Figure 10. Comparison of water level differences in the tracer test monitoring wells. Prior to these measurements, it was unclear whether the 1000-foot barrier would influence groundwater stages because of the high permeability of the Biscayne aquifer and groundwater flow around the barrier. However, the seasonal changes observed indicate that the barrier does affect both lateral and vertical groundwater flow. Groundwater temperature measurements Temperature data were collected periodically in the 6 shallow upgradient tracer test dye introduction wells and the associated downgradient shallow monitoring wells, as well as in the marsh and L-31N canal immediately west and east of the middle of the barrier wall (Appendix 1). As would be expected, the temperatures in the marsh and canal varied seasonally, while the temperature changes in the shallow monitoring wells were less significant (Figure 11). During the wet season, the average temperatures in the wells near the barrier wall were lower than the temperatures at the control site suggesting that the groundwater adjacent to the barrier was perhaps more stagnant (with the lower temperatures reflecting temperatures from the cooler dry season). July

11 L-31N Seepage Management Field Test Figure 11. Seasonal changes in average temperatures. This is also suggested from the changes in temperature between the monitoring events (for example between August and October Figure 12). The temperatures decreased in the marsh and canal during this period. The temperatures at the control site monitoring wells show similar (but smaller) decreases. However, the monitoring wells adjacent to the barrier did not show a temperature change. Figure 12. Temperature changes between monitoring events. July

12 L-31N Seepage Management Field Test Tracer Test The tracer test was designed by Tom Aley of the Ozark Underground Laboratory (OUL) in Missouri, which has extensive experience in conducting tracer tests in karst environments. All of the laboratory dye analyses were also performed by OUL. Mr. Aley s analysis of the preliminary results and all of the test results are included in Appendix 2. As shown in Figure 8, a total of 40 shallow and deep monitoring wells were installed in the vicinity of the seepage barrier and at a control site (without the seepage barrier) approximately 500 feet to the south. Six of the shallow upgradient wells were used to introduce the dye into the Miami oolite above the Q4 layer. In addition, a total of 40 canal monitoring stations with the sampler suspended at approximately the same depth as the shallow monitoring wells were established at both sites. The canal stations were installed in groups of four (50 feet upstream of the dye introduction well and 0, 50, and 100 feet downstream). The relative locations and depths of the wells and canal stations relative to the barrier wall and the site geology are shown in Figure 12. Figure 12. Geologic cross-section showing monitoring locations. The dye concentrations were analyzed using activated carbon samplers, which provide an integrated concentration for the period during which they are suspended in water. The activated carbon continually adsorbs and accumulates the dye, which is eluted and quantified in OUL s lab after collection. Two sets of carbon packs were placed in the wells and canal prior to dye introduction on October 13, 2010 to check for potential dye interferences (there were none). Carbon packs were collected from the wells and canal on day 1, 2, 4, 7, 14, 21, 28, 35, 49, 63, and 77 after introduction of the tracer. Three dye introductions were performed at both the control and barrier sites, with Rhodamine WT July

13 L-31N Seepage Management Field Test in the north and south wells and Fluorescein in the center wells. The different dyes were utilized to be able to potentially identify flow paths. Results 1. Dye was detected in both the canal and shallow downgradient well samples at both the barrier and control sites in the first set of samples collected approximately 24 hours after dye introduction. The dye could initially be identified as entering the canal at several discrete locations, but over time due to canal flow and wind, the dye spread over a much larger area. Figure 13 shows the Fluorescein distribution two days after dye introduction at the center location at the barrier and control sites. Figure 13. Fluorescein detections after two days barrier (left) and control (right) sites. 2. Four months after dye introduction, water samples were obtained from the dye introduction wells. Dye could still be visually identified at the introduction wells at the barrier site, while no dye was visible at the control site (Figure 14). These results suggested that the groundwater flow was influenced in the vicinity of the barrier. Figure 14. Dye introduction wells at completion of tracer test (four months after introduction). 3. The influence of the barrier was also suggested by the cumulative dye concentrations in the shallow downgradient monitoring wells (Figure 15). The wells at the barrier site had higher cumulative concentrations than the wells at the control site, suggesting more stagnant flow conditions in the vicinity of the barrier. The low concentrations in the northern well at the control site can be explained by the observation that the July

14 L-31N Seepage Management Field Test dye, rather than moving directly east to the canal, moved to the southeast and missed both the shallow monitoring well and canal station east of the introduction well Cumulative Dye Concentration Wall N40 No-Wall S40 Day 1 Day 2 Day 4 Day 7 Day 14 Day 21 Day 28 Day 35 Day 49 Cumulative Dye Concentration Wall N41 No-Wall S41 Day 1 Day 2 Day 4 Day 7 Day 14 Day 21 Day 28 Day 35 Day Cumulative Dye Concentration Wall N42 No-Wall S42 Day 1 Day 2 Day 4 Day 7 Day 14 Day 21 Day 28 Day 35 Day 49 Figure 15. Cumulative tracer concentrations measured in downgradient shallow wells. 4. The cumulative canal results were more variable than those for the wells. The cumulative concentrations for each dye introduction location were calculated by adding the concentrations in the 4 canal stations associated with the dye introduction, minus four times the concentration of the dye detected at the nearest upstream canal station. The dye moved downstream in the canal during the testing period and the purpose of subtracting the concentration at the upstream station was to eliminate any dye that originated from an upstream dye introduction. There was not a consistent relationship between the cumulative concentrations at the barrier and control sites (Figure 16). Higher concentrations were detected in the southern canal station group at the control site (relative to the barrier site), which is what would be expected as a result of greater groundwater flow at the control site. The same relationship might have been detected at the northern canal station group, but at the control site it was observed that the dye was entering the canal south of the canal station directly east of the introduction well and therefore the overall control group concentration was lower. However, the center canal station group showed the opposite relationship with a higher cumulative concentration at the barrier site. This result raised the question of whether there was potentially a wall construction issue (perhaps due to a bad seam) in the center of the barrier. July

15 L-31N Seepage Management Field Test Cumulative Dye Concentration Wall 250 No-Wall 250 Day 1 Day 2 Day 4 Day 7 Day 14 Day 21 Day 28 Day 35 Day Cumulative Dye Concentration Wall 500 No-Wall 500 Day 1 Day 2 Day 4 Day 7 Day 14 Day 21 Day 28 Day 35 Day 49 Cumulative Dye Concentration Wall 750 No-Wall 750 Day 1 Day 2 Day 4 Day 7 Day 14 Day 21 Day 28 Day 35 Day 49 Figure 16. Cumulative tracer concentrations measured in canal samples. 5. With one exception (the northern well at the control site), dye was not detected in the deep downgradient wells at either the barrier or control sites during the wet season. This confirms the water level data which suggested slight upward flow at the barrier site during the wet season. Once the deep and shallow water levels became similar during the dry season, dye was detected in all of the deep downgradient wells. 6. A series of shallow monitoring wells were constructed upgradient of the barrier wall to potentially be able to identify flow around the barrier. Dye was detected in only one upgradient well (N7), which is located 50 feet north of the southern dye introduction well at the barrier site. Dye was first detected at low levels on Day 28, with much higher concentrations in all of five samples through Day 119. The potential flow to the north is considered anomalous, because it was anticipated that flow would be to the south in response to the regional southeasterly gradient. The shallow upgradient wells were constructed only 5 feet to the west of the barrier wall (because of the location of the levee) and it is thought that perhaps there were not additional upgradient detections because of low flow conditions immediately behind the barrier. Canal Flow Measurements The USGS monitors a group of acoustic velocity meters (AVM) in the L-31N Canal. These meters are located at distances 1, 3, 4, 5, and 7 miles south of Tamiami Trail. At AVM-1 and AVM-4, monitoring wells were installed immediately and one mile west of the L-31N Levee in order to define the water level gradient from the marsh to the canal. AVM-1 and the associated monitoring wells are located in the middle of the barrier wall. July

16 L-31N Seepage Management Field Test The daily seepage flows into the L-31N Canal between Tamiami Trail and AVM-3 (which includes the barrier) and between AVM-3 and AVM-5 (2-4 miles south [downstream] of the barrier) were calculated using data before and after construction of the barrier in August The seepage flows were plotted vs. the stage differences between the marsh and canal at AVM-1 and AVM-4, respectively (Figures 17 and 18). The data suggest lower seepage rates in the northern section of the canal (which includes the barrier) after the barrier was constructed. By comparison, the seepage flows in the southern section of the canal are similar for the same time periods before and after construction of the barrier. These data suggest that the barrier may be influencing the seepage rate into the northern section of the L-31N Canal. Stage Difference vs. Seepage Flow, Pre and Post-Wall L-31N Canal AVM3-Upstream Flow vs. G3576-AVM1 Water level 700 Seepage Rate (cfs) Seepage calculated from S-335 to AVM3 Before 8/15/2009 After 8/30/ G Stage Difference (ft) 1.5 AVM G-3576 AVM3-Upstream Flow vs. G3574-AVM1 Water level 700 Before 8/15/2009 After 8/30/2009 Seepage Rate (cfs) Stage Difference (ft) 28 Figure 17. Pre and post-barrier stage difference vs. seepage flow at AVM-1. Stage Difference vs. Seepage Flow, Pre and Post-Wall at AVM-4 L-31N Canal AVM5-AVM3 Flow vs. G3578-AVM4 Water level 300 Seepage rate (cfs) Seepage calculated from AVM3 to AVM 5 Before 8/15/2009 After 8/30/ No Wall G AVM Stage diffeence (ft) G-3578 AVM5-AVM3 Flow vs. G3577-AVM4 Water level 300 Before 8/15/2009 After 8/30/2009 Seepage rate (cfs) Stage difference (ft) Figure 18. Pre and post-barrier stage difference vs. seepage flow at AVM-4. July

17 L-31N Seepage Management Field Test Barrier integrity testing As a result of the tracer test results (rapid detection of dye in the L-31N Canal and the variability in the cumulative dye concentrations at the different canal station groups), it was decided to investigate the integrity of the barrier wall. The initial investigation was performed using a cone penetrometer (CPT) at 13 different locations along the barrier. The cone penetrometer uses a steel probe, which includes sensors to measure tip resistance, sleeve friction, and pore pressure with depth as the probe was pushed into the barrier. These measurements were used to estimate the soil type. The Ardaman & Associates report, which includes the profiles for the 13 locations, is included in Appendix 3. The tip resistance was low and uniform (suggesting a clay material) to an average depth of approximately 13.4 feet for the 13 locations. The sleeve friction and pore pressure measurements were also uniform to a similar depth. At deeper depths, the tip resistance increased until the operator stopped advancing the probe at a tip resistance of approximately 100 tons/square foot. This refusal depth was reached at an average depth of approximately 16.7 feet for the 13 locations. The deeper high tip resistance measurements suggest sandier material. Figure 19 shows representative cone penetrometer depth profiles for CPT-3 (350 feet from the south end of the barrier), CPT- 13 (150 feet from the north end) and CPT-12B (250 feet from the north end). The cone penetrometer measurements suggested uniform clay material to depths ranging from approximately 10 feet in CPT-13 to 17 feet in CPT-12B and refusal depths ranging from approximately 12.5 feet in CPT-13 to 18 feet in CPT-3. The barrier wall was proposed to a depth of 18 feet, so it would be deeper than the low permeability hard layer at approximately feet. Measurements taken during barrier construction indicated that the trencher cut the trench to a depth of greater than 18 feet and that the excavator removed the cuttings in the trench to a depth of at least 18 feet during emplacement of the cement-bentonite slurry. The CPT results suggest that the cement-bentonite barrier does not extend down to the design depth of 18 feet. As a result of the cone penetrometer tests, borings were drilled through the barrier wall at the locations of CPT-3 and CPT-13 (Figure 20). In both borings, the barrier showed consistent cement-bentonite slurry properties to depths of approximately 8 feet, with good to poor properties between approximately 8 and 14.5 feet, and a non-functional seepage barrier at depths below 14.5 feet. Several of the CPT holes remained open to the depth where the tip resistance began to increase (and presumably collapsed at deeper depths). Water levels were measured in the CPT holes and the depth-to-water was found to be at the same depth as the surrounding aquifer. These measurements suggest that the bottom of the barrier is acting as a porous connection to the aquifer. The depth measurement summary for each CPT location and the borings descriptions are included in Appendix 3. July

18 L-31N Seepage Management Field Test Figure 19. Cone penetrometer measurements within the barrier. July

19 L-31N Seepage Management Field Test CPT CPT Figure 20. Borings within the barrier adjacent to the CPT locations. July

20 L-31N Seepage Management Field Test Conclusions The primary objective of the seepage barrier test was to document the potential effectiveness of a partially penetrating barrier along the eastern boundary of Everglades National Park. The barrier was shown to be effective in affecting groundwater flow based on the following: Water level differences upgradient and downgradient of the barrier Presence of dye remaining upgradient of the barrier at the end of the test Changes in stage vs. AVM flow data before and after construction of the barrier Tracer test cumulative mass balance differences in the canal and well samples at the barrier site vs. the control site. Changes in temperature at the barrier site vs. the control site The following tracer test and barrier integrity results indicate that the cement-bentonite barrier does not extend to the design depth of 18 feet. At the two borings locations, the barrier was shown to not have been reliably installed at depths below 14 feet. Early dye detections in the canal during the tracer test Non-uniform cone penetrometer measurements at depth Borings within the barrier. July

21 Appendix 1 Groundwater stage and temperature measurements

22 L-31N Water Level Data Station number Name Depth to Water Survey elevation 8/31/ /5/ /12/ /10/ /29/2010 2/9/2011 NORTH N11 North end NIN1 Injection well - 250' NIN2 Injection well - 500' NIN3 Injection well - 750' N40 Shallow downgradient -250' N14/15 Deep downgradient -250' N41 Shallow downgradient -500' N16/17 Deep downgradient -500' N42 Shallow downgradient -750' N18/19 Deep downgradient -750' N13 South end SOUTH SIN1 Injection well - 250' SIN2 Injection well - 500' SIN3 Injection well - 750' S40 Shallow downgradient -250' S14/15 Deep downgradient -250' S41 Shallow downgradient -500' S16/17 Deep downgradient -500' S42 Shallow downgradient -750' S18/19 Deep downgradient -750' Water level (NGVD29) Station ti Survey number Name elevation 8/31/ /5/ /12/ /10/ /29/2010 2/9/2011 NORTH N11 North end NIN1 Injection well - 250' NIN2 Injection well - 500' NIN3 Injection well - 750' N40 Shallow downgradient -250' N14/15 Deep downgradient -250' N41 Shallow downgradient -500' N16/17 Deep downgradient -500' N42 Shallow downgradient -750' N18/19 Deep downgradient -750' N13 South end SOUTH SIN1 Injection well - 250' SIN2 Injection well - 500' SIN3 Injection well - 750' S40 Shallow downgradient -250' S14/15 Deep downgradient -250' S41 Shallow downgradient -500' S16/17 Deep downgradient -500' S42 Shallow downgradient -750' S18/19 Deep downgradient -750' G G L-31N canal USGS AVM-1 website

23 L-31N Temperature Data Station number Name 7/30/2010 8/31/ /5/2010 2/9/2011 NORTH (barrier) N11 North end NIN1 Injection well - 250' NIN2 Injection well - 500' NIN3 Injection well - 750' N40 Shallow downgradient -250' N41 Shallow downgradient -500' N42 Shallow downgradient -750' N13 South end SOUTH (no wall) SIN1 Injection well - 250' SIN2 Injection well - 500' SIN3 Injection well - 750' S40 Shallow downgradient -250' S41 Shallow downgradient -500' S42 Shallow downgradient -750' ENP staff gauge L-31N canal USGS AVM-1 walkway

24 Appendix 2 Tom Aley (2011) Preliminary Results Analysis of Dye Tracing Results from a Slurry Wall Test, Miami, Florida Tracer Test results summary

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37 Ozark Underground Laboratory L-31N Seepage Project MacVicar, Federico and Lamb Table 1. Results for charcoal samplers analyzed for the presence of fluorescein and rhodamine WT (RWT) dyes. Peak wavelengths are reported in nanometers (nm); dye concentrations are reported in parts per billion (ppb). OUL Station Station Name Date/Time Date/Time Date Fluorescein Results RWT Results # # Placed Recovered Recovered Peak nm Conc. ppb Peak nm Conc. ppb U1131 N1 Shallow well-200' 8/24/ /31/ /31/2010 ND ND U1124 N9 Shallow well-850' 8/24/ /31/ /31/2010 ND ND U1129 N14 Deep well-250'-22' 8/24/ /31/ /31/2010 ND ND U1130 N15 Deep well-250'-39' 8/24/ /31/ /31/2010 ND ND U1126 N18 Deep well-750'-22' 8/24/ /31/ /31/2010 ND ND U1127 N19 Deep well-750'-39' 8/24/ /31/ /31/2010 ND ND U1132 N21 Canal-0' 8/24/ /31/ /31/2010 ND ND U1125 N37 Canal-1000' 8/24/ /31/ /31/2010 ND ND U1128 N41 Shallow well -500' 8/24/ /31/ /31/2010 ND ND U1122 S1 Shallow well-200' 8/24/ /31/ /31/2010 ND ND U1114 S9 Shallow well-850' 8/24/ /31/ /31/2010 ND ND U1119 S14 Deep well-250'-22' 8/24/ /31/ /31/2010 ND ND U1121 S15 Deep well-250'-39' 8/24/ /31/ /31/2010 ND ND U1116 S18 Deep Well-750'-22' 8/24/ /31/ /31/2010 ND ND U1117 S19 Deep well-750'-39' 8/24/ /31/ /31/2010 ND ND U1123 S21 Canal-0' 8/24/ /31/ /31/2010 ND ND U1115 S37 Canal-1000' 8/24/ /31/ /31/2010 ND ND U1118 S41 Shallow well-500' 8/24/ /31/ /31/2010 ND ND U1772 N1 Shallow well-200' 10/5/ /12/ /12/2010 ND ND U1765 N9 Shallow well-850' 10/5/ /12/ /12/2010 ND ND U1770 N14 Deep well-250'-22' 10/5/ /12/ /12/2010 ND ND U1771 N15 Deep well-250'-39' 10/5/ /12/ /12/2010 ND ND U1767 N18 Deep well-750'-22' 10/5/ /12/ /12/2010 ND ND U1768 N19 Deep well-750'-39' 10/5/ /12/ /12/2010 ND ND U1773 N21 Canal-0' 10/5/ /12/ /12/2010 ND ND U1766 N37 Canal-1000' 10/5/ /12/ /12/2010 ND ND U1769 N41 Shallow well -500' 10/5/ /12/ /12/2010 ND ND U1782 S1 Shallow well-200' 10/5/ /12/ /12/2010 ND ND U1774 S9 Shallow well-850' 10/5/ /12/ /12/2010 ND ND U1779 S14 Deep well-250'-22' 10/5/ /12/ /12/2010 ND ND U1781 S15 Deep well-250'-39' 10/5/ /12/ /12/2010 ND ND U1776 S18 Deep Well-750'-22' 10/5/ /12/ /12/2010 ND ND U1777 S19 Deep well-750'-39' 10/5/ /12/ /12/2010 ND ND U1783 S21 Canal-0' 10/5/ /12/ /12/2010 ND ND U1775 S37 Canal-1000' 10/5/ /12/ /12/2010 ND ND U1778 S41 Shallow well-500' 10/5/ /12/ /12/2010 ND ND U1922 N1 Shallow well-200' 10/12/ /14/ /14/2010 ND ND U1917 N2 Shallow Well-300' 10/12/ /14/ /14/2010 ND ND U1916 N3 Shallow Well-350' 10/12/ /14/ /14/2010 ND ND U1915 N4 Shallow Well-450' 10/12/ /14/ /14/2010 ND ND U1911 N5 Shallow Well-550' 10/12/ /14/ /14/2010 ND ND U1910 N6 Shallow Well-600' 10/12/ /14/ /14/2010 ND ND U1909 N7 Shallow Well-700' 10/12/ /14/ /14/2010 ND ND U1905 N8 Shallow Well-800' 10/12/ /14/ /14/2010 ND ND U1904 N9 Shallow well-850' 10/12/ /14/ /14/2010 ND ND U1923 N10 Shallow well-(-5) 10/12/ /14/ /14/2010 ND ND U1924 N11 Shallow well-(-15') 10/12/ /14/ /14/2010 ND ND U1903 N12 Shallow Well-1005' 10/12/ /14/ /14/2010 ND ND U1902 N13 Shallow Well-1015' 10/12/ /14/ /14/2010 ND ND U1919 N14 Deep well-250'-22' downgradient 10/12/ /14/ /14/2010 ND ND U1921 N15 Deep well-250'-39' downgradient 10/12/ /14/ /14/2010 ND ND U1913 N16 Deep Well-500'-22' downgradient 10/12/ /14/ /14/2010 ND ND U1914 N17 Deep Well-500'-39' downgradient 10/12/ /14/ /14/2010 ND ND U1907 N18 Deep well-750'-22' downgradient 10/12/ /14/ /14/2010 ND ND Page 1 of 19

38 Ozark Underground Laboratory L-31N Seepage Project MacVicar, Federico and Lamb Table 1. Results for charcoal samplers analyzed for the presence of fluorescein and rhodamine WT (RWT) dyes. Peak wavelengths are reported in nanometers (nm); dye concentrations are reported in parts per billion (ppb). OUL Station Station Name Date/Time Date/Time Date Fluorescein Results RWT Results # # Placed Recovered Recovered Peak nm Conc. ppb Peak nm Conc. ppb U1908 N19 Deep well-750'-39' downgradient 10/12/ /14/ /14/2010 ND ND U1966 N20 Canal-(-50') 10/12/ /14/ /14/2010 ND ND U1965 N21 Canal-0' 10/12/ /14/ /14/2010 ND ND U1964 N22 Canal-50' 10/12/ /14/ /14/2010 ND ND U1963 N23 Canal-100' 10/12/ /14/ /14/2010 ND ND U1962 N24 Canal-200' 10/12/ /14/ /14/2010 ND ND U1961 N25 Canal-250' 10/12/ /14/ /14/2010 ND U1961D N25 Canal-250' 10/12/ /14/ /14/2010 ND U1959 N26 Canal-300' 10/12/ /14/ /14/2010 ND U1958 N27 Canal-350' 10/12/ /14/ /14/2010 ND U1957 N28 Canal-450' 10/12/ /14/ /14/ U1956 N29 Canal-500' 10/12/ /14/ /14/ ,460 ND U1956D N29 Canal-500' 10/12/ /14/ /14/ ,650 ND U1955 N30 Canal-550' 10/12/ /14/ /14/ U1954 N31 Canal-600' 10/12/ /14/ /14/ U1953 N32 Canal-700' 10/12/ /14/ /14/ U1952 N33 Canal-750' 10/12/ /14/ /14/ U1952D N33 Canal-750' 10/12/ /14/ /14/ U1951 N34 Canal-800' 10/12/ /14/ /14/ U1950 N35 Canal-850' 10/12/ /14/ /14/ U1949 N36 Canal-950' 10/12/ /14/ /14/ U1948 N37 Canal-1000' 10/12/ /14/ /14/ U1947 N38 Canal-1050' 10/12/ /14/ /14/ U1946 N39 Canal-1100' 10/12/ /14/ /14/ U1918 N40 Shallow Well-250' downgradient 10/12/ /14/ /14/2010 ND U1912 N41 Shallow well 500' downgradient 10/12/ /14/ /14/ ,280 ND U1906 N42 Shallow Well-750' downgradient 10/12/ /14/ /14/2010 ND U1901 S1 Shallow well-200' 10/12/ /14/ /14/2010 ND ND U1896 S2 Shallow Well-300' 10/12/ /14/ /14/2010 ND ND U1895 S3 Shallow Well-350' 10/12/ /14/ /14/2010 ND ND U1894 S4 Shallow Well-450' 10/12/ /14/ /14/2010 ND ND U1890 S5 Shallow Well-550' 10/12/ /14/ /14/2010 ND ND U1889 S6 Shallow Well-600' 10/12/ /14/ /14/2010 ND ND U1888 S7 Shallow Well-700' 10/12/ /14/ /14/2010 ND ND U1884 S8 Shallow Well-800' 10/12/ /14/ /14/2010 ND ND U1883 S9 Shallow well-850' 10/12/ /14/ /14/2010 ND ND U1898 S14 Deep well-250'-22' downgradient 10/12/ /14/ /14/2010 ND ND U1899 S15 Deep well-250'-39' downgradient 10/12/ /14/ /14/2010 ND ND U1892 S16 Deep Well-500'-22' downgradient 10/12/ /14/ /14/2010 ND ND U1893 S17 Deep well-500'-39' downgradient 10/12/ /14/ /14/2010 ND ND U1886 S18 Deep Well-750'-22' downgradient 10/12/ /14/ /14/2010 ND ND U1887 S19 Deep well-750'-39' downgradient 10/12/ /14/ /14/2010 ND ND U1945 S20 Canal-(-50') 10/12/ /14/ /14/ ND U1944 S21 Canal-0' 10/12/ /14/ /14/ ND U1943 S22 Canal-50' 10/12/ /14/ /14/ ND U1942 S23 Canal-100' 10/12/ /14/ /14/ U1941 S24 Canal-200' 10/12/ /14/ /14/ ND U1939 S25 Canal-250' 10/12/ /14/ /14/ U1939D S25 Canal-250' 10/12/ /14/ /14/ U1938 S26 Canal-300' 10/12/ /14/ /14/ U1937 S27 Canal-350' 10/12/ /14/ /14/ U1936 S28 Canal-450' 10/12/ /14/ /14/ U1935 S29 Canal-500' 10/12/ /14/ /14/ , U1935D S29 Canal-500' 10/12/ /14/ /14/ , Page 2 of 19

39 Ozark Underground Laboratory L-31N Seepage Project MacVicar, Federico and Lamb Table 1. Results for charcoal samplers analyzed for the presence of fluorescein and rhodamine WT (RWT) dyes. Peak wavelengths are reported in nanometers (nm); dye concentrations are reported in parts per billion (ppb). OUL Station Station Name Date/Time Date/Time Date Fluorescein Results RWT Results # # Placed Recovered Recovered Peak nm Conc. ppb Peak nm Conc. ppb U1934 S30 Canal-550' 10/12/ /14/ /14/ U1933 S31 Canal-600' 10/12/ /14/ /14/ U1932 S32 Canal-700' 10/12/ /14/ /14/ U1931 S33 Canal-750' 10/12/ /14/ /14/ U1931D S33 Canal-750' 10/12/ /14/ /14/ U1930 S34 Canal-800' 10/12/ /14/ /14/ U1929 S35 Canal-850' 10/12/ /14/ /14/ U1928 S36 Canal-950' 10/12/ /14/ /14/ U1927 S37 Canal-1000' 10/12/ /14/ /14/ U1926 S38 Canal-1050' 10/12/ /14/ /14/ U1925 S39 Canal-1100' 10/12/ /14/ /14/ U1897 S40 Shallow Well-250' downgradient 10/12/ /14/ /14/2010 ND ND U1891 S41 Shallow well-500' downgradient 10/12/ /14/ /14/ ND U1885 S42 Shallow Well-750' downgradient 10/12/ /14/ /14/2010 ND U2170 N1 Shallow well-200' 10/14/ /15/ /15/2010 ND ND U2166 N2 Shallow Well-300' 10/14/ /15/ /15/2010 ND ND U2165 N3 Shallow Well-350' 10/14/ /15/ /15/2010 ND ND U2164 N4 Shallow Well-450' 10/14/ /15/ /15/2010 ND ND U2159 N5 Shallow Well-550' 10/14/ /15/ /15/2010 ND ND U2158 N6 Shallow Well-600' 10/14/ /15/ /15/2010 ND ND U2157 N7 Shallow Well-700' 10/14/ /15/ /15/2010 ND ND U2153 N8 Shallow Well-800' 10/14/ /15/ /15/2010 ND ND U2152 N9 Shallow well-850' 10/14/ /15/ /15/2010 ND ND U2171 N10 Shallow well-(-5) 10/14/ /15/ /15/2010 ND ND U2172 N11 Shallow well-(-15') 10/14/ /15/ /15/2010 ND ND U2151 N12 Shallow Well-1005' 10/14/ /15/ /15/2010 ND ND U2150 N13 Shallow Well-1015' 10/14/ /15/ /15/2010 ND ND U2168 N14 Deep well-250'-22' downgradient 10/14/ /15/ /15/2010 ND ND U2169 N15 Deep well-250'-39' downgradient 10/14/ /15/ /15/2010 ND ND U2162 N16 Deep Well-500'-22' downgradient 10/14/ /15/ /15/2010 ND ND U2163 N17 Deep Well-500'-39' downgradient 10/14/ /15/ /15/2010 ND ND U2155 N18 Deep well-750'-22' downgradient 10/14/ /15/ /15/2010 ND ND U2156 N19 Deep well-750'-39' downgradient 10/14/ /15/ /15/2010 ND ND U2214 N20 Canal-(-50') 10/14/ /15/ /15/2010 ND ND U2213 N21 Canal-0' 10/14/ /15/ /15/2010 ND ND U2212 N22 Canal-50' 10/14/ /15/ /15/2010 ND ND U2211 N23 Canal-100' 10/14/ /15/ /15/2010 ND ND U2210 N24 Canal-200' 10/14/ /15/ /15/2010 ND ND U2209 N25 Canal-250' 10/14/ /15/ /15/2010 ND U2209D N25 Canal-250' 10/14/ /15/ /15/2010 ND U2208 N26 Canal-300' 10/14/ /15/ /15/2010 ND U2207 N27 Canal-350' 10/14/ /15/ /15/2010 ND U2206 N28 Canal-450' 10/14/ /15/ /15/ U2205 N29 Canal-500' 10/14/ /15/ /15/ , U2205D N29 Canal-500' 10/14/ /15/ /15/ , U2204 N30 Canal-550' 10/14/ /15/ /15/ U2203 N31 Canal-600' 10/14/ /15/ /15/ U2202 N32 Canal-700' 10/14/ /15/ /15/ U2201 N33 Canal-750' 10/14/ /15/ /15/ U2199 N34 Canal-800' 10/14/ /15/ /15/ U2198 N35 Canal-850' 10/14/ /15/ /15/ U2197 N36 Canal-950' 10/14/ /15/ /15/ U2196 N37 Canal-1000' 10/14/ /15/ /15/ U2195 N38 Canal-1050' 10/14/ /15/ /15/ Page 3 of 19

40 Ozark Underground Laboratory L-31N Seepage Project MacVicar, Federico and Lamb Table 1. Results for charcoal samplers analyzed for the presence of fluorescein and rhodamine WT (RWT) dyes. Peak wavelengths are reported in nanometers (nm); dye concentrations are reported in parts per billion (ppb). OUL Station Station Name Date/Time Date/Time Date Fluorescein Results RWT Results # # Placed Recovered Recovered Peak nm Conc. ppb Peak nm Conc. ppb U2194 N39 Canal-1100' 10/14/ /15/ /15/ U2167 N40 Shallow Well-250' downgradient 10/14/ /15/ /15/2010 ND ,490 U2161 N41 Shallow well -500' downgradient 10/14/ /15/ /15/ ND U2154 N42 Shallow Well-750' downgradient 10/14/ /15/ /15/2010 ND ,920 U2149 S1 Shallow well-200' 10/14/ /15/ /15/2010 ND ND U2145 S2 Shallow Well-300' 10/14/ /15/ /15/2010 ND ND U2144 S3 Shallow Well-350' 10/14/ /15/ /15/2010 ND ND U2143 S4 Shallow Well-450' 10/14/ /15/ /15/2010 ND ND U2138 S5 Shallow Well-550' 10/14/ /15/ /15/2010 ND ND U2137 S6 Shallow Well-600' 10/14/ /15/ /15/2010 ND ND U2136 S7 Shallow Well-700' 10/14/ /15/ /15/2010 ND ND U2132 S8 Shallow Well-800' 10/14/ /15/ /15/2010 ND ND U2131 S9 Shallow well-850' 10/14/ /15/ /15/2010 ND ND U2147 S14 Deep well-250'-22' downgradient 10/14/ /15/ /15/2010 ND U2148 S15 Deep well-250'-39' downgradient 10/14/ /15/ /15/2010 ND U2141 S16 Deep Well-500'-22' downgradient 10/14/ /15/ /15/2010 ND ND U2142 S17 Deep well-500'-39' downgradient 10/14/ /15/ /15/2010 ND ND U2134 S18 Deep Well-750'-22' downgradient 10/14/ /15/ /15/2010 ND ND U2135 S19 Deep well-750'-39' downgradient 10/14/ /15/ /15/2010 ND ND U2193 S20 Canal-(-50') 10/14/ /15/ /15/ U2192 S21 Canal-0' 10/14/ /15/ /15/ U2191 S22 Canal-50' 10/14/ /15/ /15/ U2190 S23 Canal-100' 10/14/ /15/ /15/ U2189 S24 Canal-200' 10/14/ /15/ /15/ U2188 S25 Canal-250' 10/14/ /15/ /15/ U2188D S25 Canal-250' 10/14/ /15/ /15/ U2187 S26 Canal-300' 10/14/ /15/ /15/ U2186 S27 Canal-350' 10/14/ /15/ /15/ U2185 S28 Canal-450' 10/14/ /15/ /15/ U2184 S29 Canal-500' 10/14/ /15/ /15/ , U2184D S29 Canal-500' 10/14/ /15/ /15/ , U2183 S30 Canal-550' 10/14/ /15/ /15/ U2182 S31 Canal-600' 10/14/ /15/ /15/ U2181 S32 Canal-700' 10/14/ /15/ /15/ U2179 S33 Canal-750' 10/14/ /15/ /15/ ,830 U2179D S33 Canal-750' 10/14/ /15/ /15/ ,470 U2178 S34 Canal-800' 10/14/ /15/ /15/ U2177 S35 Canal-850' 10/14/ /15/ /15/ U2176 S36 Canal-950' 10/14/ /15/ /15/ U2175 S37 Canal-1000' 10/14/ /15/ /15/ U2174 S38 Canal-1050' 10/14/ /15/ /15/ U2173 S39 Canal-1100' 10/14/ /15/ /15/ U2146 S40 Shallow Well-250' downgradient 10/14/ /15/ /15/2010 ND ND U2139 S41 Shallow well-500' downgradient 10/14/ /15/ /15/ ND U2133 S42 Shallow Well-750' downgradient 10/14/ /15/ /15/2010 ND ,930 U2086 N1 Shallow well-200' 10/15/ /17/ /17/2010 ND ND U2082 N2 Shallow Well-300' 10/15/ /17/ /17/2010 ND ND U2081 N3 Shallow Well-350' 10/15/ /17/ /17/2010 ND ND U2079 N4 Shallow Well-450' 10/15/ /17/ /17/2010 ND ND U2075 N5 Shallow Well-550' 10/15/ /17/ /17/2010 ND ND U2074 N6 Shallow Well-600' 10/15/ /17/ /17/2010 ND ND U2073 N7 Shallow Well-700' 10/15/ /17/ /17/2010 ND ND U2069 N8 Shallow Well-800' 10/15/ /17/ /17/2010 ND ND U2068 N9 Shallow well-850' 10/15/ /17/ /17/2010 ND ND Page 4 of 19