CSXT Former Lakeland Yard The Use of Innovative and Iterative Assessment Techniques to Reduce Potential Redevelopment Costs

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1 CSXT Former Lakeland Yard The Use of Innovative and Iterative Assessment Techniques to Reduce Potential Redevelopment Costs CSX Samuel Ross Geosyntec Consultants John Spencer (St. Louis) and Matt Wissler (Tampa)

2 Site Information Site Location: o One mile west of downtown Lakeland, FL Site Acreage: o Main parcel 83.4 acres o Adjacent parcels 58.3, 10.5, & 8.4 acres Site History: o Railroad switching and maintenance yard dating back to early 1900 s. o Site decommissioned and all structures removed in o The Lakeland City Commission on April 3, 2001, designated the former CSX rail yard as a brownfields site. o Currently, the site is undeveloped and fenced. Active tracks border the site on the north/east and south sides and residential areas border the site to the west.

3 Summary of Environmental Investigations Petroleum (Soil/Groundwater) 1987: Initial Soil and Groundwater Investigation Identified 9 areas of hydrocarbon releases on the property and enrolled in the Florida Department of Environmental Protection (FDEP) petroleum Early Detection Incentive (EDI) program. Active remediation was performed in several areas. 2000: Evaluation of petroleum impacts in soil an groundwater. Hydrocarbons were not present in soils and groundwater impacts were minimal. Groundwater remediation was stopped. Present: Site Conditions The site is currently enrolled in the EDI program and is eligible for the Low Site Score Initiative (LSSI) program.

4 Summary of Environmental Investigations cont. Arsenic (Soil) 2000: Site Investigation Over 450 soil samples were collected across the site (~100 ft spacing). 39% of the samples contained arsenic concentrations greater that the state residential soil cleanup level 48% of the samples contained concentrations above the industrial soil cleanup target level. Arsenic concentrations were focused in the upper 2 ft interval.

5 Analysis of Soil Arsenic Concentrations using the 95% Upper Confidence Limit (UCL) For a site to reach no further action (NFA) with controls, FDEP allows for risk management (options II and III) within Florida Administrative Code (F.A.C.). The risk management options allow for the estimation of the concentrations of contaminants using a conservative estimate. The conservative estimate commonly used is the upper limit of a one-sided 95% confidence interval for the concentration mean (95% UCL). Geosyntec utilized the FDEP UCL program (FLUCL version 1.0) to calculate the UCL for the and ft bls intervals

6 Analysis of Soil Arsenic Concentrations using the 95% Upper Confidence Limit (UCL) The 95% UCL calculator was used to perform a virtual remediation scenario to reduce the average arsenic concentration to below the Industrial Soil Cleanup Target Level (I-SCTL). Through an iterative process, the virtual removal of sample locations with arsenic concentrations above 36 mg/kg were removed and replace with clean backfill until UCLs below the I- SCTL were reached. The selective removal of arsenic samples in this manner would meet the criteria for an NFA under RMO III, while limiting the volume of soil to be removed

7 Summary of Environmental Investigations cont. Aluminum (Groundwater) 2000: Site investigation Identified concentrations of aluminum above the state designated groundwater cleanup target level (GCTL). Aluminum was not identified as a material in any site processes. No release of aluminum was documented or reported at the site. Review of water quality data indicated sporadic elevated concentrations of aluminum regionally.

8 Analysis of Aluminum Concentrations in Site Groundwater Analysis of site water quality and aquifer matrix attributed aluminum concentrations to the oxidation of sulfide minerals by precipitation with high dissolved oxygen levels which decreases the ph, thereby resulting in the dissolution of the alumino-silicate aquifer matrix.

9 Analysis of Aluminum Concentrations in Regional Groundwater Geosyntec conducted a regional groundwater analysis to determine if elevated concentrations of aluminum are anthropogenic. The monitoring network consisted of site wells and three background wells The background wells were previously installed by the City of Lakeland and the Southwest Florida Water Management District (SWFWMD)

10 Development of Alternative GCTLs Geosyntec conducted a groundwater quality assessment in accordance with FDEP s guidance document Guidance for Comparing Background and Site Chemical Concentrations in Groundwater (2009) The groundwater background assessment entailed quarterly sampling of the monitoring network for a period of 1 year. Quarterly monitoring provided an alt-gctl of (880 µg/l) which was more than four times the GCTL of 200 µg/l. Using the developed alt-gctl of 880 µg/l indicated that site conditions met the criteria for closure with conditions via Risk Management Option III under (3) F.A.C

11 Closure Arsenic (soil) o Use of the 95% UCL calculator was able to reduce the excavation footprint and the overall volume of soil required to be removed Aluminum (groundwater) o Development of an alt-gctl by completing a background water quality study provided a pathway to complete the groundwater assessment and meet the criteria for site closure. The use of innovative and iterative assessment techniques allowed CSX to work closely with the regulator (FDEP) while exploring various options within the site cleanup framework to reduce cost while expediting site closure which in turn will enhance the possibility for redevelopment.