Fort Walton Beach Ordinance — 1467--Sale of Excess Real Property--S&P Mgt — reading text

from this depth were 2.60 ppm, 0.083 ppm, 24.3 ppm, and 0.023 ppm. Although spent bullets in the flat areas appeared to be limited to the upper few inches of soil and in low amounts, they were evident over large areas estimated at 13,000 and 16,000 square feet in the South and North ranges, respectively. Sieve analysis was not performed within these areas, but sixteen soil samples were collected for total lead analysis from a depth of 2.0 feet below grade from the flat areas within both ranges. Lead was reported above detection limits in only one sample (PB-28) with a concentration of 1.27 ppm. A total of nine groundwater samples were collected to assess impact to lead from the shooting range. Lead was reported above detection limits in only one sample (PW-5) with a concentration of 0.012 ppm. The maximum contaminant level (MCL) for lead in drinking water is 0.015 ppm. PW-5 was installed adjacent to the south of the north wall of the North Range. A summary of the soil and groundwater analytical results from the shooting range investigation are presented in Tables A-3 and A-4, respectively, in Attachment A. The soil and groundwater sampling location are shown in draft Figure 4, located in Attachment B. 4.0 CONCLUSIONS Based on the findings of this investigation, PPM presents the following conclusions: e There is minimal evidence of impact to soil and groundwater from petroleum hydrocarbons in the former fire training area that would warrant remedial action. TRPH concentrations in soil and groundwater were considerably below state clean-up levels. Although a concentration of toluene (0.097 ppm) was reported above the GCTL of 0.040 ppm in MW-1, the result is suspect for the following reasons: the toluene was not found in association with other petroleum constituents and MW-1 is located approximately 240 feet from the apparent source of petroleum hydrocarbons. PPM recommends that this well be re-sampled before reacting to these results. © Prior to initiation of this investigation it was known that spent bullets would most likely require mitigation if the berms are demolished. This investigation confirms that if bullet fragments larger than sand size were to be segregated, total lead concentrations 10/17/01, Phase Ii and Phase I, Fort Walton Beach Pistol Range, Project No. 231201-ESAT Mr. Pat James October 17, 2001 Page 7 in the remaining berm material exceeds FDEP's clean-up level of 400 ppm at some locations and to some depth. This investigation also confirmed that some of this material will exhibit characteristics of a hazardous waste. » Although leachable lead is present in the berm material, there does not appear to be a significant impact to groundwater from lead. 5.0 REMEDIAL COST ESTIMATE The remedial cost estimates presented in Attachment C are based on the following assumptions: e Remedial activities will not be required for petroleum hydrocarbons in the former fire training area. e Remedial activities will not be required for groundwater in the shooting range area. « Remedial activities will not be required for the exterior walls of the shooting range berms. e Remedial activities will not be performed for soils in the shooting range where bullet fragments wete not observable at the surface. e Remedial action will be required at a minimum where bullet fragments are observed at the surface. Tables C-1 and C-2 provide estimates of the total recoverable lead within the south and north ranges, respectively. Recoverable lead is defined as lead that is greater than sand size (i.e. will not pass through a No. 10 Sieve). It is estimated that the majority of the recoverable lead at the site is in the upper 3 to 6 inches of soil. An exception is in Row 3 of the north wall within the North Range where soils up to an average depth of 2.0 feet may contain recoverable lead. The total weight of recoverable lead estimated to be at the site ranges from 49 to 118 tons. Based on contractor quotations it is estimated that the breakeven quantity that would start to make lead recovery cost effective (versus landfilling everything) is 132 tons; therefore, lead recovery costs are not included in the cost estimates. Tables C-3 and C-4 provide estimates of the tons of soil impacted with total lead concentrations above 400 ppm, but would qualify as non-hazardous waste. This estimate does not include soils that may have total lead below 400 ppm, but may fail SCLP analysis thereby still requiring disposal as non-hazardous waste. Tables C-5 and C-6 provide estimates of the tons of soil that will require disposal as hazardous waste. The two greatest variables in the soil estimates are the volume of soil falling within the prescribed parameters and the conversion factor used for converting soil volume to soil tonnage. Tonnage is the only disposal parameter that can be directly measured (i.e. on 10/17/01, Phase Il and Phase Ill, Fort Walton Beach Pistol Range, Project No. 231201-ESATI Mr, Pat James October 17, 2001 Page 8 scales at the landfill) and will be the basis for unit disposal costs. In general, soil excavation contractors use a conversion factor of 1.4 tons per cubic yard (tons/cy); however, since recoverable lead will not be segregated from the soil, the conversion factor must also take into account (at least in shallow soils) that lead is 4.35 times heavier than sand. Therefore, an alternative multiplier based on the percentage of recoverable lead in surficial soils was also used. The average multiplier resulting from this estimate (1.87 tons/cy) was used to calculate the upper tonnage estimate, The standard multiplier (1.4 tons/cy) was used to calculate the lower tonnage estimate. The estimate of hazardous soil volume assumed that the excavation would require removal of hazardous soil to a depth of 1.0 to 3.0 feet deeper than the surface or 2-foot deep sample that appeared to exhibit hazardous characteristics. Soils in areas that were tested for total lead, but not TCLP, were assumed hazardous if their total concentration were similar to a sample with a elevated TCLP result. Likewise, soils that were not tested for total lead were assumed hazardous if their recoverable lead levels were similar to a sample with a elevated TCLP result. The total cubic yards of hazardous soils were estimated at 709 cubic yards or between 992 and 1,379 tons (average 1,186 tons). The estimate of non-hazardous soil volume assumed that the excavation would require some over-digging of soil below the layer of hazardous soil and at a minimum would include all soil scraped from the berm walls and ground surface to remove spent bullets. The total cubic yards of hazardous soils were estimated at 766 cubic yards or between 1,073 and 1,743 tons (average 1,408 tons). Table C-7 provides upper, middle, and lower remedial cost estimates of the entire shooting area based on the upper, average, and lower tonnage estimates, respectively. These estimates are also based on periods of 15, 12, and 10 working days estimated to be necessary to conduct excavation activities for the decreasing amounts of soil. The unit costs are based on a quotation provided by a local excavation contractor with experience in shooting range mitigation. The resulting cost to remediate the site ranges from $269,383 to $381,723. Table C-8 provides a similar breakdown of remedial costs if performed only on those portions of the shooting range that are physically on the proposed purchase. The resulting area encompasses Columns W, X, Y, and Z of the North Range and approximately 10 percent of the flat ground areas in both ranges that may require bullet removal. Due to minimal evidence of visable lead, no soil sampling was conducted during the investigation within Columns Y and Z. The lower tonnage of soil was based on what was measured in Columns W and X plus its share of the flat area. The upper tonnage assumed that the impact to soils in Columns Y and Z are the same as in W and X. This assumption is considered to be very conservative. The middle tonnage is an average of the upper and lower tonnages and may represent a more realistic upper estimate. The resulting cost to remediate the purchase area only ranges from $91,269 to $174,302 with a middle estimate of $133,688. 10/17/01, Phase If and Phase I1J, Fort Walton Beach Pistol Range, Project No. 231201-ESAM Mr, Pat James . October 17, 2001 Page 9 A final report, which will provide figures, boring logs, and laboratory analytical reports will follow this summary report. If you have any questions or need additional information, please contact us at (251) 990- 9000, , Sincerely, oye Gregéry P. Stover, P.G. GPS/erg Attachments 10/17/01, Phase i and Phase {{1, Fort Walton Beach Pistol Range, Project No. 231201-ESAII ATTACHMENTS ATTACHMENT A ANALYTICAL RESULT SUMMARY TABLES TABLE A-1 SOIL ANALYTICAL RESULTS FORMER FIRE TRAINING AREA Soil Boring| SampleID | Benzene Toluene {Etylbenzene Xylenes PAH TRPH PB-9 PB9-1 BDL BDL BDL BDL BDL 2.42 PB-10 PB10-1 BDL BDL BDL BDL BDL 11.4 PB-11 PRil-1 BDL BDL BDL BDL BDL 5.45 PB-12 PBI2-1 BDL BDL BDL BDL BDL 8.94 PB-13 PBi3-1 BDL BDL BDL BDL BDL 10.2 PB-14 PB1i4-1 BDL BDL BDL BDL BDL 3.64 PB-15 PB15-1 BDL BDL BDL BDL BDL 15.0 PB-16 PB16-1 BDL BDL BDL BDL BDL 15.1 SCTL 0.007 0.600 | 0.500 | 0.200 : 340 Notes: All concentrations reported in parts per million (ppm) BTEX analysis per EPA Method 80218 PAH analysis per EPA Method 8270C TRPH per FL-PRO (F. lorida Petroleum Residual Organics) Method BDL = Below Detection Limits SCTL = Soil Cleanup Target Levels (most stringent) TABLE A-2 GROUNDWATER ANALYTICAL RESULTS FORMER FIRE TRAINING AREA Sampling Location | Benzene | Toluene |Etylbenzene Xylenes PAH TRPH MW-1l BDL 0.097 BDL BDL BDL BDL: MW-2 BDL BDL BDL BDL BDL BDL MW-3 BDL BDL BDL BDL BDL BDL MW-4 BDL BDL BDL BDL BDL 0.608 MW-5 BDL BDL BDL BDL BDL BDL P-2 BDL BDL BDL BDL BDL BDL P-4 BDL BDL BDL BDL BDL BDL P-5 BDL BDL BDL BDL BDL BDL GCTL 0.001 0.040 0.030 0.020 | - §,000 Notes: All concentrations reported in parts per million (ppm) BTEX analysis per EPA Method 80218 PAH analysts per EPA Method &2 70C TRPH per FL-PRO (Florida Petroleum Residual Organics) Method BDL = Below Detection Limits GCTL = Groundwater Cleanup Target Levels (most stringent) T UP - Tene ity Channctenstic lerel i Ss Pre coke, TABLE A-3 SOIL ANALYTICAL RESULTS SHOOTING RANGE Sample Surface Depth 2’ BGS Location | TotalPb | TCLP Pb TotalPb | TCLP Pb A2 56 1,36 C2 719 2.47 E2 2299 28.5 2.91 G2 7674 49.9 1.24 12 836 2.93 K2 277 21.2 Pl 50 1,69 P2 49.8 1.09 P3 3821 §2.0 1255 2.60 $1 38 1260 82 3753 60.1 1093 0.083 $3 1416 1059 Ul 88.8 1229 U2 4916 48.0 42.9 U3 1822 1264 24.3 Wi 7136 0.022 4.22 0.023 W2 549 477 W3 2084 26230 PB-17 BDL PB-18 BDL PB-19 BDL PB-20 BDL.- PB-21 BDL PB-22 BDL PB-23 BDL PB-24 BDL PB-25 . BDL PB-26 BDL PB-27 BDL PB-28 1.27 PWS-2 ‘ BDL PWS-5 BDL PWS-6 BDL PWS-7 BDL Actionlevel] _ 400 5 | 400 5 | Notes: All concentrations reported in parts per million (ppm) Total Lead analysis per EPA Method 3050/60108 TCLP Lead analysis per EPA Method 13] 1/7421] Bold type Indicates Total Lead concentration exceeds Florida Clean-up Standard of 400 ppm or TCLP Lead concentration exceeds hazardous waste threshald of 5.0 ppm TABLE A-4 GROUNDWATER ANALYTICAL RESULTS SHOOTING RANGE Sampling Location | Total Lead PW-l BDL PW-2 BDL PW-3 BDL PW-4 BDL PW-5 0.012 PW-6 BDL PW-7 BDL PW-8 BDL MW-6 BDL | MCL 0.015 Notes: All concentrations reported in parts per nullion (ppm) Total Lead analysis per EPA Method 239.2 MCL = Maximum contaminant level in drinking water ATTACHMENT B DRAFT FIGURES WW ia) a +e < Z* 3 “oc z2 a& oF i S= 7 'S \ Fe o 2 T wo yee {2- #! con Neat > x6 v Fg ' IN 2) 2 2 @' (CONRETE wep 8 x 32' CONCRETE 4° x 4" WOOO RAIL FENCE, 3 2-AIGH * APPROXIMATE CENTERLINE OF DITCH want 2 Biwi! esas N ak te | +s te! \ us aM, \y POST OFFICE BOX 2478 - DAPHNE, AL 36526 BEER UATIVI A Ce » CENTERLINE , ORMDITCH ‘ ‘ 4s