Mr. Jim Christiansen August 17, 2009 Page 2 BACKGROUND

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2 Mr. Jim Christiansen August 17, 2009 Page 2 BACKGROUND In October 2000, during semi-annual monitoring, benzene and vinyl chloride were detected above the Chapter , FAC Primary Drinking Water Standard (PDWS) in detection monitoring well MW-15 at the BRL. In June 2002, the FDEP requested that OLI begin quarterly monitoring at monitoring well MW-15 (Figure 2, Attachment A). Groundwater assessments (listed below) found that the landfill was the most likely source for the benzene and vinyl chloride detections and also is the source for the relatively higher concentrations of sodium and chloride observed at MW-15. Groundwater Quality Evaluation Report, Monitoring Well MW-15. Prepared by Globex Engineering and Development for the Okeechobee Landfill, Inc., March June 2004 Geoprobe Investigation, Groundwater Quality Evaluation. Prepared by Globex Engineering and Development for the Okeechobee Landfill, Inc., August OLI identified engineering-related issues in the area of MW-15, and completed repairs and upgrades to the landfill in this area in 2004 to mitigate potential groundwater impacts. The work included upgrades to the leachate collection system (LCS), the leachate force main, and attaching the cap to the liner. OLI subsequently conducted a number of assessments of the groundwater quality in the vicinity of monitoring well MW-15. These assessments consisted of groundwater geochemical analysis, documentation of the engineering improvements, direct push assessment, and the installation of the hydraulically downgradient piezometer, P-15. The assessments concluded at that time that the upgrades effectively repaired the engineering-related issues that were identified in the area of MW-15 that caused the groundwater impacts. Two other wells in the vicinity of MW-15 (MW-7 and MW-16R) are included in the quarterly monitoring and are discussed in this report. MW-7, located approximately 500 feet west of MW- 15, was added to the quarterly monitoring of MW-15 due to a verified benzene detection in April MW-16R, located approximately 500 feet east of MW-15, was added due to a verified benzene detection in Monitoring well MW-16R replaced monitoring well MW-16 after veneer slide slope failures occurred following the 2004 hurricane season. MW-16R was placed into the evaluation monitoring program as a result of benzene, sodium, and chloride exceedances of their respective primary and secondary drinking water standards. These exceedances were likely related to upgradient issues near MW-15, but may also have been caused by the veneer slide slope failures. On July 25, 2008 a small leachate release occurred between leachate sumps 9/10 and 11/12 (in the general area of MW-15), which was reported to the FDEP on July 29, As a result, OLI evaluated the leachate collection system on the north side of the landfill. The release was traced back to the leachate force main. The evaluation indicated that a patch on the secondary

3 Mr. Jim Christiansen August 17, 2009 Page 3 containment piping (likely from a previous repair in the area) had failed. Additionally, the evaluation indicated that there likely was a leak in the main pipe from inadequately sealed joints. Though it is not possible to verify, it is possible that a slow leak may have existed in this area for some time prior to the recent failure. This is a possible cause for the continuing detections in the immediate area of MW-15, but not at P-15. Once identified, the affected area was immediately vacuumed and over excavated. Leachate did not reach the perimeter storm water ditch and appeared not to have reached shallow groundwater. Excavated leachate-impacted soil was placed back in the landfill. The entire section of the primary pipe between the two leachate sumps (9/10 and 11/12) was replaced and the secondary pipe was repaired at the affected area. QUARTERLY MONITORING EVENT As requested by FDEP, OLI has been closely tracking the VOC and indicator parameters in groundwater quality at monitoring well MW-15, nearby piezometer P-15, and monitoring wells MW-7 and MW-16R. Piezometer P-15 is located on the northern side of the site, approximately 50 feet from the limit of waste, to the northeast and side gradient of well MW-15. Monitoring well MW-7 is hydraulically upgradient from MW-15, and monitoring well MW-16R is hydraulically downgradient of MW-15. Locations of these monitoring sites, which bracket MW- 15, are shown on Figure 2, Attachment A. Due to the limited number of wells that are monitored during the quarterly monitoring event, a groundwater contour map was not prepared for this report. Rather, groundwater contour maps are included in the semi-annual monitoring reports that measure all site monitoring wells and provide a comprehensive snapshot of site water levels. Concentrations for the parameters of concern (benzene, vinyl chloride, sodium, and chloride) are listed in Table B-1, Attachment B. Time series plots for benzene, sodium, and chloride are included in Attachment C for MW-7, MW-15, MW-16R, and P-15. Sampling and Analysis The current monitoring program requires the quarterly sampling of monitoring wells MW-7, MW-15, MW-16R, and piezometer P-15 for the field and laboratory parameters listed below. The 2009 First Quarterly Sampling data were obtained during sampling conducted January 21, Field Parameters Static water level before purging Specific conductivity ph Dissolved oxygen

4 Mr. Jim Christiansen August 17, 2009 Page 4 Turbidity Temperature Color and sheens by observation Laboratory Parameters Chloride Sodium Benzene Vinyl Chloride Attachment B includes the laboratory analytical data and field forms. Attachment C includes Table C-1 listing current and historical groundwater quality detections and exceedances for benzene, vinyl chloride, sodium, and chloride. Exceedances are concentrations in excess of the PDWS, Chapter , FAC, Secondary Drinking Water Standards (SDWS), or Chapter , FAC, Groundwater Cleanup Target Levels (GCTLs). Attachment D includes the laboratory analytical report (i.e., data and field forms). Attachment E includes a CD containing a PDF copy of the report and the electronic data deliverable (EDD) files in the ADaPT format. Analytical Results for Monitoring Well MW-7 During the July 2009 quarterly sampling event, benzene was detected in monitoring well MW-7 above the laboratory method detection limit but below its PDWS. The concentration of benzene detected at this well has not exceeded the PDWS since sampling in April of A time series plot of benzene concentrations is shown on Plot C-1, Attachment C. Vinyl chloride has not been detected at monitoring well MW-7 above the laboratory method detection limit since monitoring of the well began in October Sodium concentrations (Plot C-2, Attachment C) were below the PDWS of 160 milligrams per liter (mg/l) in monitoring well MW-7 (50 mg/l) and have remained below the PDWS since at least October Chloride concentrations (Plot C-2, Attachment C) at MW-7 were below the SDWS of 250 mg/l in monitoring well MW-7 (110 mg/l) and have remained below the SDWS since at least as early as October Analytical Results for Monitoring Well MW-15 Benzene concentrations (Plot C-3, Attachment C) exceeded the PDWS of 1 µg/l in monitoring well MW-15 (3.0 µg/l) for the July 2009 quarterly sampling event. In general, benzene concentrations have been fluctuating above the PDWS since monitoring began in October 2000 with concentrations ranging between approximately 1 and 4 µg/l since Following the October 2008 event concentrations of benzene have declined.

5 Mr. Jim Christiansen August 17, 2009 Page 5 Vinyl chloride (Plot C-4, Attachment C) was not detected above the practical quantitation limit (PQL) in monitoring well MW-15 during the January 2009 monitoring event. Vinyl chloride concentrations have been at or below the PDWS of 1.0 µg/l since January 2004 with the exception of a slight exceedance of 1.1 µg/l in October Sodium concentrations (Plot C-5, Attachment C) were below the PDWS of 160 mg/l in monitoring well MW-15 (86 mg/l). In 2004 OLI identified engineering related issues in the area of MW-15 and completed repairs and upgrades to the landfill in this area to mitigate potential impacts to groundwater. As a result, the concentrations of sodium have decreased after Chloride concentrations (Plot C-5, Attachment C) were below the SDWS of 250 mg/l in monitoring well MW-15 (140 mg/l). In general, the concentrations of chloride have decreased since The decline in concentrations of benzene, sodium, and chloride since 2004 indicates that the 2004 and 2008 repairs to the LCS have resulted in improved groundwater quality in this area. The groundwater quality is anticipated to continue to improve in time as a result of the recent repairs to the LCS. Analytical Results for Piezometer P-15 Benzene (Plots C-6 and C-7, Attachment C) was not observed in piezometer P-15 above the laboratory practical quantitation limit in the current sampling event and has been below the PDWS of 1.0 µg/l since October 2007, with the exception of the April 2009 monitoring event. The April 2009 value was not confirmed during the July 2009 monitoring event. A time series plot is shown on Plot C-6, Attachment C. The decrease in concentration of benzene at P-15 shows that the current area with benzene above the PDWS is limited to the area around MW-15. Vinyl chloride (Plot C-8, Attachment C) was not observed in piezometer P-15 above the laboratory method detection limit. Vinyl chloride concentrations have been at or below the PDWS of 1.0 µg/l since May 2004 with the exception of a slight exceedance of 1.1 µg/l in April Sodium concentrations (Plot C-9, Attachment C) were below the PDWS of 160 mg/l in piezometer P-15 (19 mg/l) and have remained below the PDWS since monitoring of the piezometer began in October These results have remained relatively consistent since November 2004 and are lower than those detected in monitoring well MW-15. Chloride concentrations (Plot C-9, Attachment C) were below the SDWS of 250 mg/l in piezometer P-15 (22 mg/l) and have remained below the SDWS since monitoring of the piezometer began in October Similar to sodium, these results have remained consistent since November 2004 and are significantly lower than those detected in upgradient monitoring well MW- 15.

6 Mr. Jim Christiansen August 17, 2009 Page 6 Analytical Results for Monitoring Well MW-16R The benzene concentration (Plot C-10, Attachment C) in monitoring well MW-16R during the current sampling event was below the PDWS with an estimated concentration of 0.40 I µg/l. Benzene concentrations have been at or below the PDWS of 1.0 µg/l since January In general, the concentrations of benzene exhibit a decreasing trend since June Vinyl chloride was not observed in monitoring well MW-16R above the laboratory method detection limit. Vinyl chloride concentrations have been at or below the PDWS of 1.0 µg/l since at least as early as Sodium concentrations were below the PDWS of 160 mg/l in monitoring well MW-16R (95 mg/l). In general, the concentrations of sodium exhibit a decreasing trend since April A time series plot is shown on Plot C-11, Attachment C. Chloride concentrations were below the SDWS of 250 mg/l in monitoring well MW-16R (170 mg/l). Similar to sodium, the concentrations of chloride exhibit a decreasing trend since June A time series plot is shown on Plot C-11, Attachment C. The analytical results show that the groundwater quality has been improving at MW-16R since June The initial exceedances of the PDWS and SDWS at MW-16R (benzene, sodium, and chloride) were likely related to upgradient issues in the MW-15 area, but may have been related to the veneer slide slope failure that occurred following the 2004 hurricane season. Groundwater quality has been improving since repairs to the MW-15 area and the adjacent slide slopes, and benzene, vinyl chloride, sodium, and chloride concentrations are now below the PDWS and SDWS. CONCLUSIONS Overall, the concentrations of benzene, vinyl chloride, sodium, and chloride remain below historical highs and have trended generally downward over time. These trends suggest that the corrective measures implemented in 2004 and 2008 to address the exceedances continue to be effective. Levels of benzene at MW-15 above the PDWS remain limited to area around MW-15. Evaluation of the MW-15 area will continue with the quarterly monitoring events. In other affected wells, concentrations of benzene, vinyl chloride, sodium and chloride have consistently declined after the initial remedial measures and remain below the applicable standards. The sampling of monitoring wells MW-7, MW-15, well MW-16R, and piezometer P-15 for benzene, vinyl chloride, sodium, and chloride will continue on a quarterly basis.

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8 ATTACHMENT A FIGURES

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11 ATTACHMENT B TABLES OF EXCEEDANCES AND DETECTIONS

12 TABLE B-1. SUMMARY OF HISTORICAL GROUNDWATER QUALITY ANALYTICAL RESULTS (BENZENE, VINYL CHLORIDE, SODIUM, AND CHLORIDE ONLY) BERMAN ROAD LANDFILL, OKEECHOBEE COUNTY, FLORIDA MW-7 MW-15 P-15 MW-16/MW-16R* Benzene 1 Vinyl Chloride 1 Sodium 1 Chloride 2 Benzene 1 Vinyl Chloride 1 Sodium 1 Chloride 2 Benzene 1 Vinyl Chloride 1 Sodium 1 Chloride 2 Benzene 1 Vinyl Chloride 1 Sodium 1 Chloride 2 Parameter (µg/l) (µg/l) (mg/l) (mg/l) (µg/l) (µg/l) (mg/l) (mg/l) (µg/l) (µg/l) (mg/l) (mg/l) (µg/l) (µg/l) (mg/l) (mg/l) MCL /20/ U 5 U U 1 U NI NI NI NI 1 U 1 U /20/ U 1 U NI NI NI NI /27/ U 1 U U 1 U NI NI NI NI /7/ U 1 U NI NI NI NI 1 U 1 U /26/ U 1 U U 1 U NI NI NI NI 1 U 1 U /24/ U 1 U NI NI NI NI 1 U 1 U /30/ NI NI NI NI /10/ U 1 U NI NI NI NI 1 U 1 U /25/ NI NI NI NI /18/ U 1 U NI NI NI NI /20/ NI NI NI NI 1 U 1 U /16/ U 1 U NI NI NI NI 1 U 1 U /31/ NI NI NI NI /30/ U 1 U NI NI NI NI 1 U 1 U /25/ NI NI NI NI /9/ U 1 U NI NI NI NI 1 U 1 U /21/ NI NI NI NI /10/ NI NI NI NI U /28/ U 1 U U /19/ U /20/ U U U 1 U /25/ U /15/ /3/ U U U 1 U /13/ U 1 U U U 1 U /13/ U 1 U U U /18/ U U U U 1 U /1/ U 1 U U U /18/ U U U U /18/ U 1 U U U /14/ /21/ U 1 U U U /2/ /5/ U 1 U U U U /6/ I 1.0 U I /6/ /3/ I I I U /24/ I 1 U I U /2/ U 1 U I I 1 U U /25/ I 1 U 65 I I 87 I I 1U 24 I U /1/ I 1 U U I 1U I 1 U /31/ U 1 U 48 V I 92 V U 1 U I 1 U 140 V /8/ U 1 U U 1 U U 1 U /21/ I 1 U U U 1 U I 1 U /7/ I 0.4 U U U 25 V I 0.4 U /14/ I 0.4 U U I 0.4 U I 0.4 U NOTES: 1 Parameter maximum concentration limit (MCL) is a Primary Drinking Water Standard ( F.A.C.). 2 Parameter MCL is a Secondary Drinking Water Standard ( F.A.C.) = Parameter not analyzed. 4. mg/l: milligrams per liter. 5. µg/l: micrograms per liter. 6. Yellow Shaded values indicate parameter concentrations exceeded primary or secondary Drinking Water Standards. 7. U=Analyte concentration was below the laboratory detection limit (value shown). 8. NI = Location not installed. 9. I = Analyte detected above detection limt but below quanitiation limit. 10. * = Monitoring well MW-16R was installed in October 2005.

13 ATTACHMENT C TIME SERIES PLOTS

14 Berman Road Landfill Plot C-1. Benzene Time Series Plot for MW ug/l Year Nondetect Benzene 1 Prepared by: SCS Engineers

15 Berman Road Landfill Plot C-2. Chloride and Sodium Time Series Plot for MW mg/l Year Nondetect Chloride Sodium 1 Prepared by: SCS Engineers

16 Berman Road Landfill Plot C-3. Benzene Time Series Plot for MW ug/l Year Nondetect Benzene 1 Prepared by: SCS Engineers

17 Berman Road Landfill Plot C-4. Vinyl Chloride Time Series Plot for MW ug/l Year Nondetect Vinyl chloride 1 Prepared by: SCS Engineers

18 Berman Road Landfill Plot C-5. Chloride and Sodium Time Series Plot for MW mg/l Year Nondetect Chloride Sodium 1 Prepared by: SCS Engineers

19 Berman Road Landfill Plot C-6. Benzene Time Series Plot for P ug/l Year Nondetect Benzene 1 Prepared by: SCS Engineers

20 Berman Road Landfill Plot C-7. Benzene, Chloride, and Sodium Time Series Plot for P ug/l mg/l Year Nondetect Benzene Chloride Sodium 1 Prepared by: SCS Engineers

21 Berman Road Landfill Plot C-8. Vinyl Chloride Time Series Plot for P ug/l Year Nondetect Vinyl chloride 1 Prepared by: SCS Engineers

22 Berman Road Landfill Plot C-9. Chloride and Sodium Time Series Plot for P mg/l Year Nondetect Chloride Sodium 1 Prepared by: SCS Engineers

23 Berman Road Landfill Plot C-10. Benzene Time Series Plot for MW-16R ug/l Year Nondetect Benzene 1 Prepared by: SCS Engineers

24 Berman Road Landfill Plot C-11. Chloride and Sodium Time Series Plot for MW-16R mg/l jan jul jan jul jan jul jan jul jan jul jan Month / Year Nondetect Chloride Sodium 1 Prepared by: SCS Engineers

25 ATTACHMENT D LABORATORY ANALYTICAL REPORT

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102 ATTACHMENT E CD OF REPORT & ADaPT FILES