f+vu>~ 00%] FINAL PHASE FIELD SAMPLING PLAN FOR II (a) GUN AND MORTAR POSITIONS OF THE CAMP EDWARDS IMPACT AREA GROUNDWATER QUALITY STUDY MASSACHUSETTS MILITARY RESERVATION CAPE COD, MASSACHUSETTS Prepared for NATIONAL GUARD BUREAU ARLINGTON, VIRGINIA Prepared by OGDEN ENVIRONMENTAL AND ENERGY SERVICES 239 Littleton Road, Suite IB Westford, Massachusetts 01886 MMR-0904.doc 01/07/00 - Jonathan Bourne Public Library X 19 Sandwich Rd. MA FV>»irn«, 02&32 Final Phase (a) Gun/Mortar FSP II DISCLAIMER: This document has been prepared pursuant to a government administrative order (U.S. EPA Region I SDWA Docket No. 1-97-1019) and is subject to approval by the U.S. Environmental Protection Agency. The opinions, findings, and conclusions expressed are those ofthe authors and not necessarily those ofthe Environmental Protection Agency. MMR-0904.doc i 01/07/00 7 1 Final Phase (a) Gun/Mortar FSP II a m TABLE OF CONTENTS Page INTRODUCTION 1.0 1 2.0 INSTALLATION AND SAMPLING METHODS FOR MONITORING WELLS 5 3.0 SAMPLING & ANALYSIS METHODS FOR SOILS 6 4.0 SAMPLE IDENTIFICATION 9 4.1 Groundwater Profile Samples 9 4.2 SoilSamples 10 REFERENCES 5.0 10 Tables Table 1. Coordinates forGun and Mortar Positions (Stateplane, NAD83, Zone 4151, meters) 2 Table 2. Estimated WaterTable Depths for Gun/Mortar Position Borings 6 Figures Figure 01. Gun and Mortar Position Locations.... Figure 02. Proposed So Sample Grid Locations for Old Gun Position 1 14 Figure 03. Proposed So Sample Grid Locations forGun Position 2 15 Figure 04. Proposed So Sample Grid Locations forOld Gun Positions 2 and 3 along Herbert Road 16 Figure 05. Proposed So Sample Grid Locations forOld Gun Positions 3 and 4 along Howe Road 1 Figure 06. Proposed So Sample Grid Locations forOld Gun Position 4 offofTurpentine Road 18 Figure 07. Proposed So Sample Grid Locations forGun Position 5 19 Figure 08. Proposed So Sample Grid Locations forGun Position 6 20 Figure 09. Proposed So Sample Grid Locations for Gun Position 8 21 Figure 10. Proposed So Sample Grid Locations for Gun Position 10 22 Figure 1 1. Proposed So Sample Grid Locations for Gun Position 1 23 Figure 12. Proposed So Sample Grid Locations for Gun Position 12 24 Figure 13. Proposed So Sample Grid Locations forGun Position 14 25 Figure 14. Proposed So Sample Grid Locations forOld Gun Position 15 26 Figure 15. Proposed So Sample Grid Locations forGun Position 17 27 Figure 16. Proposed So Sample Grid Locations forOld Gun Position 19 28 Figure 17. Proposed So Sample Grid Locations for Gun Position 20 29 Figure 18. Proposed So Sample Grid Locations for Gun Position 22 30 Figure 19. Proposed So Sample Grid Locations for Gun Position 24 31 Figure 20. Proposed So Sample Grid Locations for Mortar Position 1 32 Figure 21. Proposed So Sample Grid Locations for Old Mortar Position 1 33 Figure 22. Proposed So Sample Grid Locations for Mortar Position 2 34 Figure 23. Proposed So Sample Grid Locations forOld Mortar Position 2 35 MMR-0904.doc 11 01/07/00 . Final Phase (a) Gun/Mortar FSP II Figure 24. Proposed Soil Sample Grid Locations forOld Mortar Position 3 36 Figure 25. Proposed Soil Sample Grid Locations for Mortar Position 4 37 Figure 26. Proposed Soil Sample Grid Locations for Mortar Position 7 38 Figure 27. Proposed Soil Sample Grid Locations for Mortar Position 9 39 Figure 28. Proposed Soil Sample Grid Locations forOld H Range Mortar Position 40 Figure29. Locations ofExisting and Proposed Control Grids 41 Figure 30. Locations ofFiring Positions forGroundwater Investigations 42 Figure 31 Proposed Monitoring well location for MP-3 43 Figure 32. Proposed Soil Sampling Grid Locations for Former F Range 44 Figure 33. Plan ofSoil Sampling Grid 45 Figure 34. Proposed Soil Sampling Grid Locations forGun Position 16 46 Attachments Attachment A. Regulatory Agency Comments 47 MMR-0904.doc 111 01/07/00 Final Phase (a) Gun/Mortar FSP II 1.0 Introduction The following text was extracted from the Phase 11(a) Workplan (Ogden, 1998a) and Change 1 to the Phase 11(a) Workplan (Ogden, 1999a). Phase I ofthe IAGS included investigation ofrepresentative gun and mortar positions in accordance with the final Action Plan (ETA, 1997) and the Final FSP for Gun and Mortar Positions (Ogden, 1998c). The locations investigated were selected, based on records ofthe quantities ofrounds fired, to be representative of positions in either low, medium, or high use. The Phase I results indicate that there is no evidence ofmunitions-related contaminants at mortar positions (Ogden, 1998b). At gun positions, the results indicate the presence ofpropellants in shallow soil, at frequencies proportional to the amount ofgun position use. ... EPA has requested additional sampling in light ofthe limited number ofpositions sampled in Phase I. The following text from the Phase 11(a) Workplan describes the investigation approach (Ogden, 1999a). To evaluate the previous soil composite sampling scheme, the previously sampled high use gun position (Area 16 or GP-16) will be resampled. The nine-point grid with the highest PEP concentrations from Phase I will be overlaid with two five- point grids, each measuring 22.3x22.3 feet. The two five-point grids will have all five subsamples separately homogenized and split into two subsamples, one used for the composite and the other analyzed as a discrete sample. The composite results from this round ofsampling will be compared with the previous Phase I sampling results for assessment ofthe compositing method in relation to the gun and mortar positions. In addition, the individual discrete results for each depth and grid will be averaged and compared with the composite results to evaluate the effect ofheterogeneity and the utility ofthe compositing method. Additional soil investigations will be conducted at the remaining mortar and gun positions following the conceptual sampling approach employed in Phase I. That is, composite samples will be collected and analyzed for Phase I parameters from the firing locations and at downwind and downrange locations. Also, groundwater investigations will be performed at the four gun and mortar positions which appear to have been used the heaviest, based on rounds fired and propellant burned. The use data that are currently available indicate that these eight positions consist ofGP-6 (highest propellant), GP-16 (highest rounds), GP-20 MMR-0904.doc 1 01/07/00 Final Phase (a) Gun/Mortar FSP II (2nd highest propellant), GP-14 (2nd highest rounds), MP-3 (highest propellant), MP-8 (highest rounds), MP-4 (2nd highest propellant and rounds), and MP-1 (3rd highest propellant) (Ogden, 1998c). No additional data have become available regarding firing point utilization since the Phase II (a) Workplan and Change 1 document were prepared. Therefore, the above locations for groundwater investigations are still appropriate. The locations offiring positions for gun and mortar are shown in Figure 1. A list ofavailable coordinates for the firing positions is provided in Table 1. Table 1 also shows the priority ranking for investigation ofeach position, as indicated in an 8 September 1999 letter from EPA. The CS-18 study ofGP-9 (1994 and before) concluded that there is no imminent threat to human health from this site. Regulatory concerns, however, are focused on the protection ofa sole source aquifer used for public drinking water. To answer all the regulatory issues, additional work is being proposed for CS-18 under the IRP prior to regulatory concurrence on site close out. The study will be conducted in 2000 and includes obtaining a more definitive characterization ofsoils, a current characterization of groundwater quality and groundwater movement, and preparation ofan updated screening level risk evaluation for both human health and ecological receptors. The IRP recommendation for additional work or No Further Action will follow these studies. Table Coordinates for Gun and Mortar Positions (Stateplane, NAD83, Zone 4151, meters) 1 . EPA Gun & Mortar Position ID Easting (x- Northing (y- Area Priority coordinates) coordinates) Gun Positions 19 GP-l-OLD 278105.97 825582.38 50 30 GP-2 277976.19 828752.44 51 31 GP-2-OLD 278440.22 825533.94 52 32 GP-3-OLD 278661.63 825490.38 53 14 GP-3-OLD 278848.84 826276.31 63 15 GP-4-OLD (Howe) 278648.91 826270.50 55 18 GP-4-OLD (Turpentine) 279655.70 826117.01 56 13 GP-5 278446.03 826364.63 57 9 GP-6 279237.50 826818.13 58 Phase I GP-7 278978.31 826870.56 17 -> GP-8 278454.09 826963.06 59 IRP CS-18 GP-9 279387.97 826210.94 3 GP-10 279232.88 826232.56 60 4 GP-11 278979.69 826244.69 61 MMR-0904.doc 01/07/00 Final Phase (a) Gun/Mortar FSP II m a m a Table 1. Coordinates for Gun and Mortar Positions (Stateplane, NAD83, Zone 4151, meters) EPA Gun & Mortar Position ID Easting (x- Northing (y- Area Priority coordinates) coordinates) 33 GP-12 278344.88 833265.94 62 5 GP-14 277806.72 833719.88 54 16 GP-15-OLD 278323.69 827471.75 64 Phase GP-16 277610.63 833662.31 16 I 20 GP-17 279615.41 834303.63 65 Phase GP-18 279418.34 834197.81 18 I 34 GP-19-OLD 277345.42 832756.43 66 10 GP-20 279135.94 833589.19 67 22 GP-22 280526.88 833929.94 68 25 GP-24 277073.47 828826.13 69 Mortar Positions 8 MP-1 279828.22 827005.31 70 26 MP-1-OLD 278452.56 828886.38 71 27 MP-2 279325.44 827090.69 72 23 MP-2-OLD 276887.75 830391.69 73 Phase MP-3 278496.47 828067.13 20 I 24 MP-3-OLD 277113.03 831499.30 74 6 MP-4 278487.72 828367.06 75 Phase MP-5 278515.34 828820.69 21 I Phase MP-6 278516.97 828877.94 20 I 28 MP-7 278570.22 828969.88 76 Phase I MP-8 278507.28 829024.81 19 29 MP-9 282976.85 831031.13 77 12 Former F Range 278913.03 825575.06 78 Former H Range 281679.96 827699.35 79 1 Table 1 includes most ofthe known current and former firing positions for artillery and mortar, as identified in the U.S. Army Corps ofEngineers (USACE) Archives Search Report (March 1999). The IBC Range and Former R Range are locations where mortar, as well as other munitions, were fired. Considering the multi-purpose nature ofthese ranges, investigations ofthese locations are being proposed through the Phase II (b) Workplans. The remainder ofthis FSP provides information for field personnel engaged in soil and groundwater investigations as indicated above. The groundwater investigation consists of MMR-0904.doc 01/07/00 Final Phase (a) Gun/Mortar FSP II installing eight monitoring well nests at selected gun and mortar positions, as described in Section 2 below. The soil investigation initially consists ofsampling GP-16 using the revised sampling approach described in Section 3 below. The soil investigation will be expanded to include other gun and mortar positions when the results from sampling GP- 16 are available and have been discussed with the EPA and MADEP. Soil sampling locations at the other gun and mortar positions are indicated in Figures 2 to 28, 31, and 32. These locations were chosen using the Phase I sampling approach of focussing on the cleared firing position, and including samples downwind and downrange ofthe position. The numbers ofsamples per position were determined based on the size ofthe cleared area and using a sampling density ofapproximately three grids per acre. The figure showing each position uses the aerial photograph for the year showing the largest apparent clearing. The aerial photos available for this FSP were from 1943, 1955, 1966, 1977, 1986, 1991, and 1994. Detailed sampling procedures for these locations will be based on the GP-16 results and will be documented in an addendum. Sampling is also proposed at four new "control areas" as indicated in Figure 29. Control areas were defined in Phase I as areas outside the probable influence ofa potential contaminant source. Control areas were sampled in Phase I to characterize a nearby "clean" area for comparison with the focal area samples. Ten control grids were included in Phase I sampling, including five for gun positions and five for mortar positions. Locations ofthese grids are also shown in Figure 29. Grid BGHMAA, located at the center ofGP-16, had the highest 2,4-dinitrotoluene (2,4- DNT) concentration (600 ug/kg) during Phase I sampling, and is the grid at GP-16 that is selected for initial sampling. The only sample having a higher detected explosive concentration was BGHCAA. reported to have pentaerythritol tetranitrate (PETN) present at a concentration of36,000 ug/kg. Photo Diode Array (PDA) data for this sample were not reviewed during Phase I to confirm the results. Subsequent review ofthe Phase I PDA data indicates that the PETN detection was a false positive. The explosive 2,4-DNT was detected in five out often locations at GP-16. MMR-0904doc 4 01/07/00