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SDMS Document 115555 TRANSMITTAL To: Ms. Caroline Kv^ran From: John Virgie and Edward Nemecek Date: 6/20/97 ^ Subject: Draft Remedial Investigation Work Plan Addendum - Phase III Virgin Island Chemical Site St. Croix, U.S. Virgin Islands Project Number:35241.7.2 Enclosed is the Draft Remedial Investigation Work Plan Addendum - Phase III (7 bound copies and 1 unboimd copy) for the subject site. If you have any questions or require additional information, please call John Virgie or Ed Nemecek at (609) 936-0700. T V ^ '^Lj cc:Distribution Harding Lawson Associates - - — ^ Engineering and Environmental Services 1 1 14 Washington Road, Building 7 Princeton Junction, New Jersey 08550 - (609) 936-0700 - Fax (609) 936-1020 302232 s Draft Remedial Investigation Work Plan Addendum • Phase 111 Virgin island Chemical Site St. Croix, U. S. Virgin islands Prepared for Island Chemical Company HLA Project No. 35241 7.2 DRAFT John S. Virgie, P.G. Senior Geologist DRAFT Edward A. Nemecek, R.G., CPG Principal Hydrogeologist Regional Geosciences Manager June 20, 1997 Harding Lawson Associates f P f ^ T l Engineering and Environmental Services " 14 Washington Road, Building 7 Princeton Junction, NJ 08550 - (609) 936-0700 302233 DRAFT CONTENTS 1.0 BACKGROUND 1 1.1 Introduction 1 1.2 Site Description 1 1.2.1 Site Location 1 1.2.2 Site Structures ; 1 1.2.3 Site Setting 1 1.3 Previous Activities and Data Needs 2 1.4 Objective 3 2.0 WORK PLAN TASKS 5 2.1 AST Area Investigation 5 2.1.1 Soils 5 2.1.2 Groundwater 5 2.2 Former Drum Area Investigation 6 2.2.1 Soils 6 2.2.2 Groundwater 6 2.3 Onsite Storm Drain Sediment and Soil Sampling 6 2.4 Offsite River Gut and Bethlehem Gut Sampling 6 2.5 Groundwater Sampling 7 2.6 Evaluation of Groundwater Flow Direction and Aquifer Characteristics 7 2.7 Data Validation 7 2.8 Data Evaluation and Reporting 7 2.9 Meetings, Progress Reports, and Presentations to EPA 7 2.10 Management and Disposal of Investigation-Derived Wastes 7 3.0 SUPPLEMENTAL REMEDIAL INVESTIGATION TASKS 8 3.1 Field Sampling Program 8 3.1.1 Soil and Groundwater Investigation at AST Area 8 3.1.2 Site-Wide Groundwater Quality Sampling 12 3.1.3 Onsite Groundwater Elevation Monitoring 12 3.1.4 Evaluate Groundwater Flow Direction In Deep Water-Bearing Zone 12 3.1.5 Onsite Storm Drain Sediment and Soil Sampling 13 3.1.6 Offsite River and Bethlehem Gut Samphng 14 . 3.2 Data Validation 15 3.3 Data Evaluation 15 g:\3524i\phaselll\wpadd.DOC Harding Lawson Associates i IA) O IO to GJ DRAFT 3.4 Update/Track ARARs 16 3.5 Project Meetings and Reporting 16 3.5.1 Meetings with EPA 16 3.5.2 Monthly Progress Reports 16 3.6 Management of Investigation-Derived Waste 16 4.0 ANTICIPATED SCHEDULE 17 TABLES 1 Summary of Proposed Samples FIGURES 1-1 Site Location Map 1-2 Location of Monitoring and Production Well and Preliminary Assessment Soil Boring 1-3 Regional Geologic Map 2-1 Flow Chart 3-1 Proposed Sampling Locations - AST Area 3-2 Double-Cased Monitoring Well Construction Diagram 3-3 Approximate Location of Offsite Production Wells 3-4 Proposed Sampling Locations - Onsite and River Gut APPENDIXES A CONTAINERS, PRESERVATION, PACKAGING, AND SHIPPING REQUIREMENTS B HELD SAMPLING PLAN ADDENDUM C QUALITY ASSURANCE PROJECT PLAN ADDENDUM DISTRIBUTION o to to U) g:\3524i\phaselll\wpadd.DOC Harding Lawson Associates DRAFT 1.0 BACKGROUND 1.1 introduction Harding Lawson Associates (HLA) has prepared this Remedial Investigation Work Plan Addendum on behalf of Island Chemical Corporation (ICC) as part of the Remedial Investigation (RI) of the Virgin Island Chemical site (site) located in St. Croix, U.S. Virgin Islands. This RI Work Plan Addendum is intended to address issues discussed and agreed to during the meetings on October 17, 1996 and May 12, 1997, with the U.S. Environmental Protection Agency, Region II (EPA) and comments presented in EPA's letter dated December 23, 1996. The work described in this document will be performed in accordance with the project Sampling and Analysis Plan (SAP), Health and Safety Plan (HASP), and Quality Assurance Project Plan (QAPP) provided with the Remedial Investigation Work Plan (Work Plan), dated March 17, 1994 and revised August 5, 1994 (HLA, 1994). Addenda to these documents are included as Appendixes. 1.2 Site Description 1.2.1 Site Location The site occupies approximately 3 acres in south central St. Croix, U.S. Virgin Islands (Figme 1-1). The site is located on Melvin Evans Highway (Route 66), approximately 1,500 feet north ofthe Alexander Hamilton Airport. The property is located on Plot 13Q of Estate Bethlehem Middle Works at 17°42'35" north latitude, 64°47'26" west longitude. The site is bordered to the northeast and southeast by an intermittent stream identified as the River Gut. It is bordered to the west by an undeveloped lot and to the southwest by Route 66. A concrete batch plant and two automobile repair shops are located to the east of the site, across the River Gut. An asphalt paving company is located north-northwest of the site across the River Gut. 1.2.2 Site Structures The facility is currently abandoned. The current layout of the facility is shown in Figure 1-2. Major onsite structures include the following: Laboratory and Warehouse Building Maintenance Building Above-Ground Storage Tank (AST) Farm Concrete Pads adjacent to AST Farm (former AST locations) Loading Dock Concrete Storage Pad Centrifuge and Dryer Building Reactor Process Area Former Process Pit (filled during previous work at this site) Generator Building Pump Building 250,000-Gallon Fire Water AST 1.2.3 Site Setting U) The site is located in a valley. Surface elevations at the site range from approximately 30 to 40 feet o above mean sea level (MSL). Land to the southwest (approximately 200 feet) and to the east ^ (approximately 1,000 feet) of the site slopes steeply upward to roughly 150 to 200 feet above MSL. (^j g:\3524i\phaselII\wpadd.DOC Harding Lawson Associates DRAFT The ground surface slopes gently across the site from southwest to northeast. Ground surface just beyond the northern and eastern fence lines slopes steeply downward approximately 12 to 15 feet into the River Gut. An earthen berm, approximately 4 feet high, partially separates the AST farm in the westem part of the facility from the remainder of the site. On the western side of the berm, runoff drains from southwest to northeast. Surface drainage on the eastern portion of the site is controlled by the buildings, concrete paved areas, and two storm drains that channel runoff along the southeastern site boundary (Figure 1-2). Flow in the River Gut is intermittent and generally occurs only as a result of sufficient precipitation during the rainy season, between September and December. The Caribbean Sea is located approximately 4,500 feet south of the site. Based on previous investigations, shallow soils beneath the site consist of alluvium. The geology and hydrogeology of St. Croix were discussed in detail in the Work Plan and in the Draft Data Summary Report (DSR), dated August 15, 1995 (HLA, 1995). Figure 1-3 presents a generalized geologic map of the island. 1.3 Previous Activities and Data Needs Between September 1984 and March 1986, Enviro-Science, Inc. (ESI) performed a series of investigations of selected portions of the site. In September 1985 and March 1986, EPA collected several samples from the site. Between March 1989 and April 1991, EPA performed a preliminary assessment and a drum removal action. In February 1991, NUS Corporation (NUS) collected groundwater, soil and sediment samples as part of a Preliminary Assessment'Site Investigation, performed on behalf of EPA. Data generated during these activities were summarized in the Remedial Investigation Work Plan (HLA, 1994). From October 1994 to August 1995, HLA implemerited the EPA-approved Remedial Investigation Work Plan. Results of work performed through August 1995 were summarized in the Data Summary Report (DSR) (HLA, 1995). The key findings of that investigation were: • Volatile organic compounds (VOCs) were detected in soils and shallow groundwater samples collected at monitoring well MW-1 in the vicinity of Tanks 8 and 9 in the above-ground storage tank (AST) area. • The two primary constituents of concern identified in previous investigations, pyridine and chloroform, were not detected in any soil or groundwater samples collected during HLA's 1995 investigation. • The visual reconnaissance performed after site clearing revealed no evidence of additional potential' source areas. Following EPA's review of the DSR, HLA prepared a proposal (April 12, 1996) and a draft Phase II RI Work Plan (May 15, 1996) to address the following as requested by EPA: • Obtain additional information on shallow groundwater flow direction(s) over time through the use of automated water level recorders. • Characterize the extent of impacted soil and groundwater identified in the vicinity of Tanks 8 and 9 in the AST area. • Obtain groundwater quality data near the center of the site (Former Process Pit Area) by installing and sampling monitoring well MW-2 well as originally proposed in the RI Work Plan (HLA, 1994). to o to From May through August 1996, HLA implemented the EPA-approved Phase II RI Work Plan. Results ; to of the work performed during the completion of Phase II activities were summarized in the Draft ^ g:\3524i\phaseimwpadd.DOC Harding Lawson Associates DRAFT Supplemental Data Summary Report, dated September 13, 1996 (HLA, 1996). The key findings of that investigation were: • The lateral and vertical extent of VOCs in soils at the AST area were defined to the north, east, and south^ of the identified source area, but not to the west (offsite). The extent of VOCs in groundwater was not defined in a locally downgradient (western) direction. • Chloroform was detected above the Federal Maximum Contaminant Level (MCL) in shallow groundwater in the vicinity of the former process pit area (Monitoring Well MW-2). • Based on several months of continuous groundwater level monitoring, a shallow groundwater divide trending north-south is interpreted to exist at the site. The groundwater flow direction across the majority of the site west of the divide is to the west and northwest, and the flow direction in the easternmost portion of the site east of the divide is to the east and northeast. On October 17, 1996 and May 12, 1997, EPA met with the respondents' and HLA to discuss the findings of the Supplemental Data Summary Report (HLA, 1996). EPA suggested that several data needs still remained and that they be addressed through supplemental investigative activities. HLA is currently performing preliminary Phase III site assessment activities from June 9 through June 20, 1997. These activities were agreed upon at the May 12 meeting and documented in HLA's correspondence to EPA dated May 19, 1997. HLA used the available data generated during the preliminary Phase III assessment in conjunction with results of the previous phases of this Remedial Investigation (RI) to develop a focused revised RTWPA for the subject site. Objectives of the Phase III RIWPA are discussed below. 1.4 Objective The objective of this phase (Phase III) of the RI is to address the following data needs identified during the October 17, 1996 and May 12, 1997, meetings with EPA which are necessary for evaluation of remedial alternatives justified by risk assessment. • Further evaluate the lateral and vertical extent (onsite and offsite) of toluene, ethylbenzene, and xylene (TEX) previously detected in soils and groundwater related to the small area near Tanks 8 and 9 in the AST area. • Evaluate background metals concentrations in onsite soils. • Estimate hydrogeologic properties (specifically hydraulic conductivity) of the shallow and deep water-bearing zones onsite. • Further evaluate the local flow direction(s) in the deeper portion of the water-bearing zone. • Install three deep monitoring wells in the vicinity of MW-2, MW-6, and a third location to be determined once the water level data from the preliminary assessment activities have been evaluated. EPA approval of the location of this well will be obtained prior to its installation. • Collect groundwater samples from all new and existing onsite monitoring and production wells to further evaluate the extent of Target Compound List (TCL) VOCs, semivolatile organic compounds (SVOCs), and Target Analyte List (TAL) metals, in groundwater. At the meeting on October 17, 1996, EPA's contractor, CDM Federal Programs, disputed that the extent of VOCs in soils had been defined lo the south of the presumed source area, because VOCs had been detected in samples from southernmost boring SBB2. HLA noted that continuous field screening of soils from 0 to 18 feet at SBB2 did not detect VOCs. The presence of VOCs in soil samples from 20 to 22 feet and 22 to 24 feet at SBB2 is attributed to capillary effects and/or fluctuating water levels associated with underlying groundwater. g:\3524i\phaselll\wpadd.DOC , Harding Lawson Associates U) o to to U) 00 DRAFT Further evaluate the possible presence of TCL VOCs, SVOCs and TAL metals in soils in one additional location onsite and TCL SVOCs and TAL metals concentrations in sediments in the River and Bethlehem guts. Update and further evaluate baseline ecological assessment information concerning potential ecological receptors and exposure pathways associated with the River Gut from the vicinity of the site to the confluence with the Bethlehem Gut. Preliminarily evaluate the potential applicability of soil vapor extraction (SVE) and/or bioventing as possible remedial altematives for soil in the AST area. Obtain available water quality data which should be routinely collected from the Fairplains Well Field supply wells from the Virgin Island Water and Power Authority. The tasks described in this RI Work Plan Addendum are designed to achieve these objectives. Following completion of these tasks, HLA will evaluate the findings of the RI and present results. o to g;\3524i\phaseimwpadd.DOC Harding Lawson Associates DRAFT 2.0 WORK PLAN TASKS Figure 2-1 presents a flow chart which summarizes the proposed tasks to be implemented to address the data needs identified in Section 1.4. The tasks are explained in detail in Section 3.0. The tasks to be completed are as follows: 2.1 AST Area Investigation 2.1.1 Soils • Install soil borings offsite (west) of previous boring SBB17/MW-6 to assess the vertical and horizontal extent of toluene, ethylbenzene, and xylene (TEX) in soils associated with the AST source area in the vicinity of monitoring wells MW-1 and MW-6. • At the request of EPA, HLA installed four additional soil borings (SBAST 1 through SBAST 4, Figure 1-2) within the general AST area during preliminary Phase III site assessment activities (conducted in June 1997) to evaluate the possible presence of additional source(s) within the AST area. Analytical data from these borings will be evaluated to determine if additional soil borings are needed to assess additional source area(s), if present in the AST area,. The EPA will be contacted to discuss the locations of additional boring(s) in the AST area, if needed. Data from previous soil boring SBEl, which was installed near the former concrete pad (Figure 3-1), will also be used in this evaluation. • Preliminarily evaluate the applicability of SVE and/or bioventing as remedial alternatives by collecting and analyzing soil samples for analysis of grain size, moisture, total organic carbon, porosity, biological numeration, and nutrients. 2.1.2 Groundwater • Evaluate the lateral extent of TEX in shallow groundwater offsite to the west of the AST area by collecting and analyzing groundwater samples in the field. Temporary wells will be installed at multiple locations. A single, offsite shallow monitoring well will be installed near the downgradient extent of the plume as determined by data collected from the temporary wells; access restrictions may limit the final well location. • Evaluate the vertical extent of TEX in groundwater beneath the AST source area by installing a double-cased monitoring well adjacent to monitoring well MW-6 (Figure 3-1). A pilot soil boring will be advanced to approximately 5 feet below the encountered water table at the location. No soil sampling will be performed in this boring (soil sampling was already performed in these areas during previous RI investigations). A steel casing will then be grouted in place at that depth to prevent cross-contamination during deeper drilling. After the grout has set for at least 24 hours, a pilot boring will be advanced through the grout. Depth-discrete Hydropunch® groundwater samples will then be collected at 10-foot intervals (starting at the interval 5 feet below the steel casing). When the targeted sample depth is reached, depth- discrete Hydropunch® groundwater samples will be collected and analyzed in the field for VOCs using the onsite field gas chromatograph (GC). Co-located samples (collected in 40 mL VOA vials with no headspace) will be obtained for laboratory analysis at a rate of one sample for every ten screening samples, or more frequently as deemed necessary. The borings will be advanced to a depth where the field determined concentration of any individual chemical does not exceed its MCL. The boring will then be advanced 10 feet below this depth, reamed to 8 inches in diameter and a 4-inch diameter , ^ monitoring well with 10 feet of screen will be installed using the procedures outlined in the SAP. (^ to • If needed, and pending the results of any additional soil investigations, shallow monitoring wells ^ may be installed dining a subsequent phase to evaluate the lateral and vertical extent of TCL VOCs, , % g:\3524i\phaseimwpadd.DOC Harding Lawson Associates 5 DRAFT SVOCs, and TAL metals in shallow groundwater in the AST area. Installation of these wells will be based on analytical results of soil samples collected from borings installed in the AST area during the preliminary Phase III assessment activities. 2.2 Former Drum Area Investigation 2.2.1 Soils • Three former drum areas were tentatively identified using the February 13, 1971 aerial photograph contained in the U.S. Environmental Photographic Interpretation Center's document entitled Site Amalysis; Island Chemical Company, St. Croix, Virgin Islands dated April 1987. At the request of EPA, three borings were installed onsite at the possible former location of 238 drums. Two borings were installed onsite at the possible former location of 64 drums. One boring was installed onsite at the possible former location of 8 drums. These borings were installed and sampled (Figure 1-2) during preliminary Phase III site assessment activities to evaluate the possible presence of additional source(s) within these former drum areas. Analytical data from soil samples collected from these borings will be evaluated to determine if additional soil borings are needed to assess the additional source area(s) in the former drum areas, if present. The EPA will be contacted to discuss the locations of additional boring(s) in the former drum areas, if needed. 2.2.2 Groundwater • If needed, additional monitoring well(s) may be installed to evaluate the lateral and vertical extent of TCL VOCs, SVOCs, and TAL metals in shallow groundwater in the former drum areas. Installation of these wells will be based on analytical results of soil samples collected from borings installed in the former drum areas during the preliminary Phase III assessment and other soil borings installed during a subsequent phase. 2.3 Onsite Storm Drain Sediment and Soil Sampling • Collect seven sediment samples within the onsite drainage system and two soil samples from one onsite boring in the central drainage system(Figure 3-4). The sediment samples will be analyzed for TCL SVOCs, TAL metals, total organic carbon, particle grain size, pH, redox, percent moisture and conductivity. The soil samples will be analyzed for TCL VOCs, SVOCs and TAL metals. 2.4 Offsite River Gut and Bethlehem Gut Sampling • Secure access to collect samples from offsite locations in River Gut. Collect two samples from each of three borings in River Gut and fourteen sediment samples within the River Gut (Figure 3-4). Sampling in River Gut will be conducted upstream, across from, and downstream of the site. These data will be evaluated with data from previous sampling activities; access restrictions may limit the number of samples to be collected. The sediment samples will be analyzed for TCL SVOCs, TAL metals, total organic carbon, particle grain size, pH, redox, percent moisture and conductivity. The samples from the borings will be analyzed for TCL VOCs, SVOCs and TAL metals. • Six samples will be reserved for collecting sediments from the portions of the River Gut bank at surrounding commercial facilities such as the Golden Grove Correctional Facility, Meridian Engineering, Virgin Islands Asphalt Products Company and Charlie's Concrete in areas of observed waste material not already targeted by this investigation. A total of three sediment samples will be collected from the Bethlehem Gut starting at the confluence of the River and Bethlehem Guts. One •' (jj sample will be collected at the confluence with the River Gut, one sample will be collected 500 feet ; o upstream from the confluence and one sample will be collected 1,000 feet upstream from the ^ confluence (Figure 3-3). The samples will be analyzed for TCL SVOCs, TAL metals, total organic ; rf^ carbon, particle grain size, pH, redox, and conductivity. I-* g:\3524i\phaselII\vvpadd.DOC Harding Lawson Associates DRAFT • If needed, additional monitoring well(s) may be installed to evaluate the lateral and vertical extent of TCL VOCs, SVOCs, and TAL metals in shallow groundwater beneath the River Gut or Bethlehem Gut. Installation of these wells will be based on analytical results of soil samples from these guts during this phase and installed in the next phase, if needed. 2.5 Groundwater Sampling • Evaluate site-wide distribution of TCL VOCs, SVOCs and TAL metals in groundwater by collecting groundwater samples from onsite and offsite wells including the newly installed shallow well(s), newly installed deep wells, shallow monitoring wells, and deep former production wells using low- flow purging techniques. 2.6 Evaluation of Groundwater Flow Direction and Aquifer Characteristics • Perform downhole video surveys to evaluate the screen intervals and the integrity of onsite former production wells Pi and P2. • Measure the water level in the new deep wells and existing onsite and accessible offsite production/monitoring wells to evaluate flow direction in the deep portion of the water-bearing zone. HLA will attempt to obtain construction details and driller or geologic logs of the onsite and offsite production/monitoring wells from sources on St. Croix. • Estimate the hydrogeologic properties of the shallow and deep water-bearing zones by performing slug tests at one onsite shallow monitoring well (MW-2) and one onsite deep monitoring well (MW- 2D) and by monitoring water level responses in nearby monitoring wells during development of the newly installed monitoring wells. 2.7 Data Validation • Confirmation level laboratory data generated for investigative samples will be validated as discussed in the Work Plan. 2.8 Data Evaluation and Reporting • Interpret, evaluate and summarize the results of the proposed supplemental investigation, incorporate the results with previous investigations, and prepare a Supplemental Data Summary Report for submittal to the EPA. 2.9 Meetings, Progress Reports, and Presentations t o EPA • One meeting with EPA will be requested following receipt, interpretation, and validation of data generated during the implementation of this RI Work Plan Addendum and prior to preparation of a final Draft Data Summary Report Addendum (DSRA) or preparation of the RI report, whichever is appropriate. At that time, the findings will be discussed along with the format for the final report. Additional meetings with EPA may be conducted as needed or upon request. • Monthly progress reports will continue to be submitted to EPA on the 15th day of each month (or first business day thereafter). The monthly progress reports will be prepared in accordance with the Administrative Order on Consent and the Work Plan. ^ to 2.10 Management and Disposal of Investigation-Derived Wastes f^ to • Investigation-derived waste (IDW) will be managed in accordance with procedures outlined in the Work Plan. g;\3524i\phaseIII\wpadd.DOC Harding Lawson Associates DRAFT 3.0 SUPPLEMENTAL REMEDIAL INVESTIGATION TASKS The tasks to be completed during this phase of the RI are discussed below. Specifics of well locations, wells to be sampled, soil sample locations, analytical parameters, and other activities may be modified based on possible legal access restrictions, physical restrictions and on the findings of various phases of each task. A summary of the proposed samples to be collected is presented in Table 1. EPA will be notified of any substantive changes. These changes, if necessary, will be discussed with and approved by EPA prior to implementation. Work will be conducted following the procedures outlined in the previously approved Work Plan and associated supporting documents. 3.1 Field Sampling Program 3.1.1 Soil and Groundwater Investigation at AST Area 3.1.1.1 Property Access and Well Permits ICC representatives have secured the majority of offsite property access agreements necessary for this investigation. Prior to mobilization, ICC will make its best efforts to secure necessary property access to offsite sediment, soil and groundwater sampling locations described in this Work Plan. Prior to mobilization, HLA or the drilling contractor will obtain the appropriate permits from the Virgin Island Department of Planning and Natural Resources to install the proposed monitoring wells. 3.1.1.2 Soil Sampling AST Area Soil sampling will be performed to: • Investigate the lateral and vertical extent of TEX in soil offsite and adjacent to Tanks 8 and 9 (west of boring SBB17) • Assess the potential for other potential source areas in the general AST area • Collecfpreliminary data regarding the applicability of soil vapor extraction and bioventing in the AST area as a possible remedial alternatives Proposed boring locations are shown on Figure 3-1. Three soil borings will be installed approximately 20 feet west, west-northwest, and northwest of previous boring SBB17. Additional offsite borings may be installed based on photoionization detector (PID) field screening results and field observations. Four borings (SBAST-1 through SBAST-4) were installed and sampled onsite during the preliminary Phase in site assessment activities conducted in June 1997. These borings were located within the AST area (Figure 1-2) north and south of the previously defined impacted area to investigate the possibility of other source areas. Analytical data from soil samples collected from these borings will be evaluated to determine if additional sampling is necessary to assess the extent of impact in the AST area. The EPA will be contacted to discuss the locations of additional boring(s) in the AST area, if needed. The results from soil boring SBE-1 (installed during Phase I activities adjacent to former Tank 20) will be used in conjunction with data from the four new borings to evaluate the general AST area (no PID readings were measured and no VOCs were detected above the detection limit in soil samples collected from the boring installed at this location). - OJ o Soil sampling will follow the detailed procedures described in the EPA-approved Work Plan and to supporting documents and which have been implemented by HLA in previous phases of this RI. At t*^ each boring, soil samples will be collected continuously from ground surface to the water table using a g:\3524i'phaselll\wpadd.DOC Harding Lawson Associates 00 DRAFT split-spoon. Upon opening the split-spoon, the sample will be physically scored and screened for the presence of organic vapors using a PID. A sample from each 2-foot interval will then be immediately placed into a laboratory-prepared container sealed and stored in a cooler. Additional sample volume from each interval if available, will be placed into resealable plastic bags and screened in the field for headspace organic vapors using the procedures described in the Work Plan. Procedures for sample handling, management, and shipping will be implemented as described in the Work Plan. Two soil samples from each boring will be analyzed: one from directly above the water table and one from the sample interval with the highest PID reading. If no PID readings are observed, sample intervals will be based on lithology as described in the RI Work Plan. Soil samples will be analyzed for TCL VOCs. Shelby tube samples will be collected from two of the onsite borings for analysis of grain size, moisture, total organic carbon (TOC), and porosity to preliminarily evaluate the applicability of SVE as a remedial alternative for soil in the AST area. These samples will be collected using 3-inch outside diameter Shelby tubes. The Shelby tubes will be constructed of stainless steel tubing or equivalent materials. The lower end is beveled to form a tapered cutting edge. The upper end of the Shelby tube is fastened to a check valve that helps hold the sample in place as it is being withdrawn. The Shelby tube is positioned at the upper portion of the interval to be sampled, and advanced the length of the tube (typically 2 feet). The advancement of the Shelby Tube is performed smoothly and steadily by the application of hydraulic pressure from the drill rig to the drilling rod connected to the Shelby tube. The Shelby tube is extracted using the same mechanisms operated in reverse. Storage, shipping and handling of these samples is described in the revised draft SAP. The analysis of the Shelby tube soil samples will be performed by Raytheon Environmental Services Laboratory located in Boothwyn, Pennsylvania. Two soil samples will be collected from two separate onsite soil borings for analysis of total heterotrophic plate count and a hydrocarbon utilizer (HCU) bacteria count to preliminarily evaluate the applicability of bioventing as a remedial alternative for soil in the AST area. These two soil samples will also be submitted for analysis to evaluate the available nutrient levels. The nutrient profile will include analysis of TOC, alkalinity, iron, ammonia, sulfate, sulfide, nitrate, nitrite, pH, and ortho phosphorus. One of the soil sampling locations for the bacteria counts will be collected from a soil sampling interval which exhibits relatively high PID readings. The remaining sample will be collected from a sampling interval which exhibits moderate PID readings. Analysis of total heterotrophic plate count and an HCU bacteria count samples will be performed by HLA, if approved by EPA. Former Drum Areas Three former drum areas were tentatively identified using the February 13, 1971 aerial photograph contained in the U.S. Environmental Photographic Interpretation Center's document entitled Site Analysis; Island Chemical Company, St. Croix, Virgin Islands dated April 1987. At the request of EPA, three borings were installed onsite at the possible former location of 238 drums. Two borings were installed onsite at the possible former location of 64 drums. One boring was installed onsite at the possible former location of 8 drums. These borings (Figure 1-2) were installed and sampled during preliminary phase III site assessment activities to evaluate the possible presence of additional source(s) within these former drum areas. Analytical data from soil samples collected from these borings will be evaluated to determine if additional soil borings are needed to assess the former drum areas. The EPA will be contacted to discuss the locations of additional boring(s) in the former drum areas, if needed. Background Areas Three background samples (Figure 3-4) will be collected from areas on the site that have not been impacted by site operations to evaluate the background concentrations of metals in onsite soil. These to samples will be collected from the O-to-6-inch depth interval and will be analyzed for TAL metals. , "^ g:\3524i\phaselll\vvpadd.DOC Harding Lawson Associates 00 o to • DRAFT 3.1.1.3 Shallow Groundwater Investigation AST Area The purpose of this task is to characterize determine the areal extent of the dissolved TEX in groundwater, where the TEX concentrations exceed their respective MCL. Groundwater samples will be collected at the water table at three locations (Figure 3-1) approximately 50 feet west, west- northwest, and northwest of MW-6 using temporary monitoring wells. The temporary monitoring wells will be constructed of 2-inch diameter PVC screen and riser. A 5-foot long screen will be positioned across the static water level. A 6.5-inch diameter boring for the temporary wells will be advanced using hollow-stem auger drilling methods to a depth approximately 4 feet below the water table. The water table will be located by evaluating split-spoon samples collected from the borehole. The temporary well will be installed through the auger and the augers will be removed. The water level measuring points will be marked and later surveyed to allow for groundwater elevation calculations. An oil-water interface probe will be used to measure static water levels and monitor for the presence of liquid phase hydrocarbons in each temporary well. Once the water level in the boring has remained constant for at least 15 minutes, a Teflon® bailer will be lowered into the well to retrieve a groundwater sample which will be transferred to laboratory-cleaned 40-mL glass vials. The groundwater sample will be analyzed onsite as soon as possible using a portable GC calibrated for TEX. The data collected through field GC screening will be classified as screening level data. Further investigation, if necessary, will be guided by the results of the onsite GC analysis of groundwater samples from the three temporary wells. If TEX concentrations exceed their respective MCLs, additional temporary wells will be installed and sampled using the above procedures at incremental 50-foot radial locations (i.e., approximately 100 feet from MW-6). If the results of all three of the first groundwater samples collected from the initial temporary well are below MCLs, then a 4- inch diameter monitoring well will be installed at the furthest downgradient or western location. The well will be installed and developed as described in the RIWP. The well screen will be 10 feet long, have a slot size of 0.020 inches, and extend approximately 5 feet below the encountered water table depth. Development water will be placed in 55-gallon drums and staged onsite pending disposal or stolen. The temporary wells will be removed within 2 weeks after their installation. The PVC screen and riser will be extracted and the borings will be abandoned as described in the RIWP. Former Drum Areas If needed, additional monitoring well(s) will be installed to evaluate the lateral and vertical extent of TCL VOCs, SVOCs, and/or TAL metals in shallow groundwater in the former drum areas. Installation of these wells will be based on analytical results of soil samples collected from borings installed in the former drum areas during the preliminary Phase III assessment activities. The EPA will be contacted to discuss the locations of additional monitoring well(s) in the former drum areas, if needed. 3.1.1.4 Onsite Deep Groundwater Investigation The vertical extent of TCL VOCs in groundwater onsite will be evaluated by installation of double-cased monitoring wells to be located near MW-2, MW-6 and a third location to be determined once the water level data from the preliminary assessment activities can be evaluated. EPA approval of the location of this well will be obtained prior to it's installation. A pilot soil boring will be advanced to approximately 5 feet below the encountered water table at each location. No soil sampling will be performed in these borings (soil sampling was already performed in these areas during previous RI investigations). A steel Ui casing will then be grouted in place at that depth to reduce the potential for cross-contamination during o deeper drilling. The steel casing will be installed as follows. The pilot boring will be reamed to a ^ diameter of 12-inches to the designated depth using mud rotary drilling techniques. An 8-inch ' j ^ diameter steel casing with welded joints will then be lowered to the bottom of the boring and centered. ^ Cement grout will then be emplaced in the annular space around the casing via a tremie pipe from the g;\3524i\phaselIl\vvpadd.DOC Harding Lawson Associates 10 DRAFT • bottom up. The drilling fluid in the annular space will be displaced by the grout, the drilling equipment will be decontaminated and the drilling fluid inside the casing will be circulated thoroughly with potable water until visible drilling fluids have been removed and relatively clear water remains inside the casing. After the grout has set for at least 24 hours, a pilot boring will be advanced through the grout. Depth- discrete Hydropunch® samples will be collected at 10-foot intervals (starting at the interval 5 feet below the steel casing). The Hydropunch® sampler is a specialized tool designed to obtain groundwater samples within the saturated zone without the installation of a monitoring well. It is constructed of stainless steel and Teflon with viton O-rings. The Hydropunch® sampler is designed to be driven by the slide hammer commonly used for obtaining split-spoon samples. The Hydropunch® sampler will be removed from the boring between each sampling interval and decontaminated using procedures described in the SAP. When the targeted sample depth is reached, the Hydropunch® sampler is opened by pulling back the outside sleeve of the tool. Soil friction holds the drive cone in place as the sleeve moves up. Once opened, groundwater flows through the dedicated disposable screen into the tool from the surrounding formation. After allowing sufficient time for groundwater to fill the sample chamber, a Teflon bailer will be lowered into the borehole to retrieve a groundwater sample which will be transferred to laboratory-prepared 40-mL glass vials. These samples will be analyzed for VOCs using the onsite field GC. Co-located confirmation samples (collected in 40 mL VOA vials with no headspace) will be obtained for laboratory analysis at a rate of one confirmation sample for every ten screening samples. Samples will be analyzed for TCL VOCs by CLP methodology. These confirmation samples will be preserved and handled as described in Section A2.8 of the RIWP. The borings will be advanced to a depth where concentrations of any individual chemical do not exceed MCLs. The boring will then be advanced 10 feet below this depth, reamed to 8 inches in diameter and a 4-inch diameter monitoring well with a 10-foot screen will be installed, using the procedures outlined in the SAP. A diagram of the proposed double-cased well is provided as Figure 3- 2. Automated water level devices (e.g., TUBERs or equivalent) will be installed in each of the newly installed deep monitoring wells. 3.1.1.5 Aquifer Testing Preliminary information on the hydrogeologic properties of the shallow and deep portions of the water- bearing zone will be obtained by conducting the following activities. During development of the newly installed wells, water levels will be continuously monitored in the well being developed and in the nearest wells using an automated data logger-pressure transducer system. This will provide information regarding possible hydraulic communication between the shallow and deep portions of the water- bearing zone. Monitoring of recovery of water levels in selected onsite wells after development will also provide information on relative hydraulic conductivity between the upper and lower portions of the aquifer. Slug tests will also be performed at one onsite shallow monitoring well and one deep monitoring well to supplement the data collected during well development. 3.1.1.6 Survey The location and elevation of the temporary wells, soil borings and new wells will be surveyed as specified in the Work Plan. The horizontal and vertical position will be surveyed with respect to the Puerto RicarvVirgin Islands plane coordinate system (North American Datum of 1983, or NAD 83) to the nearest tenth of a foot. The well locations will be converted from plane coordinates to latitude and ' Jo longitude. The vertical position of the temporary wells, soil borings, and new wells will be surveyed 'j;;^ with respect to Mean Sea Level (MSL) to the nearest hundredth of a foot. Well elevations to be surveyed include the top of inner casing, top of outer casing, and adjacent ground surface. The location g:\3524i\phaselli\wpadd.DOC Harding Lawson Associates 11 OJ o 1 ^ . DRAFT of the inner casing elevation measurement will be permanently marked for future water level measurements. Temporary well elevations to be surveyed include the top of casing and adjacent ground surface. The ground surface at each of the soil borings will also be surveyed. 3.1.2 Site-Wide Groundwater Quality Sampling After installation and development of the new wells in the AST area, groundwater samples will be collected from the onsite and offsite monitoring wells and the deep production wells (P-1 and P-2). The site-wide groundwater sampling will be conducted to further evaluate groundwater quality at the site. Specifically, objectives of the site-wide groundwater sampling are (1) to evaluate the extent of TEX compounds related to the AST area, and (2) to assess the presence of chloroform previously reported at MW-2. Groundwater sampling will be conducted approximately 2 weeks after installation and development of the new wells. HLA will supply precipitation data for the two-week period prior to groundwater sampling activities are implemented. At the request of EPA, low-flow (minimal drawdown) groundwater sampling procedures (as described in Puis and Barcelona, 1995) will be utilized in lieu of the procedures described in the Work Plan. A 2- inch diameter Grundfos® Redi Flo 2 submersible sampling pump or a bladder pump will be utilized for purging and sampling. As recommended by Puis and Barcelona (1995), HLA will purge and sample using a flow rate not to exceed 0.5 liters per minute. Water quality probes will be used to measure key indicator parameters (temperature, pH, specific conductance, redox, dissolved oxygen, and turbidity) during purging. After stabilization of the water quality indicator parameters, groundwater samples will be collected directly from the pump discharge line. Sample containers, preservation, shipping, and chain-of-custody procedures will be implemented as described in the Work Plan. Groundwater samples will be analyzed for TCL VOCs using CLP protocols. As requested by EPA, local precipitation records for the two-week period prior to each groundwater sampling event will be submitted with the groundwater analytical data. 3.1.3 Onsite Groundwater Elevation Monitoring Groundwater elevations have been monitored at the site using automatic water level recorders (TUBERs) installed at MW-1 and MW-3 in August 1995 and at MW-4 and MW-5 in April 1996. Four recorders are currently installed. The most recent data (since June 1997) will be downloaded from these recorders during the upcoming field program. These data will be combined with water levels which will be measured manually from all wells prior to the site-wide groundwater sampling event. Groundwater contour maps mil be prepared for selected dates using the water table elevations calculated from the manual and automated measurements. 3.1.4 Evaluate Groundwater Flow Direction In Deep Water-Bearing Zone HLA has recently received documents from the U.S. Geological Survey (USGS) entitled Water Resources Data Puerto Rico and the U.S. Virgin Islands Water Year 1992, USGS Water-Data Report PR-92-1,1993 and Water Wells on St. Croix, U.S. Virgin Islands, Open File Report 91-503, 1994 . HLA has also requested the most recent Water Resources Data report and any other relevant information concerning water level data on St. Croix from the USGS. HLA will utilize these data in conjunction with information obtained from the onsite and offsite deep wells, as described below, to estimate the regional flow direction of the deeper portion of the water-bearing zone. 3.1.4.1 Onsite Deep Wells The onsite deep production wells (P-1 and P-2) will be evaluated using a video television camera to OJ assess well integrity and screen intervals. After the survey, water levels will be measured at P-1 and P- ^ 2. These data will be combined with water level data from the new onsite deep wells to assess onsite lo flow direction in portions of the deep water-bearing zone. 1 ^ -J g:\3524i\phaselII\wpadd.DOC Harding Lawson Associates 12 DRAFT 3.1.4.2 Offsite Deep Wells The purpose of this task is to measure groundwater levels in the offsite production wells to aid in evaluation of regional flow direction in the deep water-bearing zone in the vicinity of the site. The existence of these wells was field verified during the preliminary Phase III assessment activities. The locations have been plotted based on existing records and aerial photograph review. The offsite production wells from which water level measurements will be collected include (see Figure 3-3): • Former WAPA well directly south of site • Well at Charlie's Concrete Company (east of site) • Well at Meridian Engineering (northwest of site) • Virgin Islands Port Authority (VIPA) Wells 1 and 2 (west of site) • U.S. Geological Survey wells downstream of the site near confluence with Bethlehem Gut • Well at Carr's. • Well at Zenon Construction ICC has secured access agreements for the above wells. Prior to mobilization for the field sampling program, HLA will attempt to obtain relevant information regarding the construction, usage, and status of these wells. Groundwater levels will then be measured at the wells using the procedures outlined in the Work Plan. The groundwater elevations calculated from the offsite and onsite deep wells will be used to evaluate flow direction in the deep portion of the water-bearing zone. Water level contour map(s) will be prepared. 3.1.5 Onsite Storm Drain Sediment and Soil Sampling 3.1.5.1 Sediment Sampling Samples of sediments will be collected at onsite locations shown in Figure 3-4. Samples SDl, SD2, and SD3 will be collected from the central storm drain system. Samples SD4 and SD7 will be collected from sediments, if present, in the southern storm drain system. These samples will only be collected if sufficient material exists for analytical purposes. The locations may be modified in the field to nearby depositional areas where adequate sediment volumes are available. Sample SDl will be collected from the storm drain at a point approximately 25 feet below the process area. Sample SD2 will be collected from the junction of the lines forming the central storm drain system. Sample SD3 will be collected from the settling basin which collects drainage from the central storm drain system before discharging to the River Gut. Sample SD4 will be collected from within the southern storm drain system at a point approximately 10 feet upgradient of the point where this system discharges to River Gut. Sample SD7 will be collected from sediments, if present, within the southern storm drain system at a point approximately 50 feet upgradient of SD4. The samples will be analyzed for TCL SVOCs, 'TAL metals, total organic carbon, particle grain size, pH, redox, and conductivity. 3.1.5.2 Soil Sampling As requested by the EPA, one boring was to be installed at the approximate location where elevated photoionization detector (PID) field screening results were detected during the excavation of the former central storm drain constructed of 55-gallon drums attached end to end. Historical information and reports concerning the removal of the 55-gallon discharge line do not indicate the exact locations where elevated PID readings were detected. Therefore the mid-point along the discharge line was chosen as a the soil boring location. ^ to Two soil samples from each boring will be analyzed: one from directly above the water table and one '^ from the sample interval with the highest PID reading. If no PID readings are observed, sample QQ g;\3524i\phasellI\wpadd.DOC Harding Lawson Associates 13 DRAFT intervals will be based on Uthology as described in the RI Work Plan. Soil samples will be analyzed for TCL VOCs, SVOCs and TAL metals. 3.1.6 Offsite River and Bethlehem Gut Sampling Samples RGlA through RGll will be collected from the River Gut stream channel. • Samples RGlA, RGlB, and RGlC will be selected in the field at locations upstream of the abandoned railroad bridge, and upstream of drainage from the bulldozed area adjacent to the site 25 feet of each other in the River Gut. These samples will be evaluated as background sediment samples. • Sample RG2 will be collected approximately 100 feet upstream of the site boundary, just downstream of the abandoned railroad bridge. Sample RG2 will be collected from the northeastern stream bank in an area of waste material observed in the fill. Sample location RG2 is located at a seep of petroleum-like material, if still present (visually identified by HLA in 1995 during ecological investigation activities), in the fill material on the northern bank of the River Gut. • Sample RG3 will be collected from the depositional area of the stream bed upstream of the former lab drain discharge. • Sample RG4 will be collected from depositional areas of the stream bed below the former lab drain. • Sample RG5 will be collected from the depositional areas of the stream bed approximately 100 feet downstream from RG4. • Sample RG6 will be collected in an area of waste material observed, if still present (visually identified by HLA in 1995 during ecological investigation activities), in the fill on the northeastern side of the River Gut bank. • Sample RG7 will be collected from the River Gut stream bed at a point approximately 50 feet upstream of the discharge of the central storm drain system. • Sample RGS will be collected from the stream bed at a point where the central storm drain system from the site discharges to River Gut. • Sample RG9 will be will be collected from the stream bed at the point where southern storm drain system from the site discharges to River Gut. • Sample RGlO will be collected from sediment deposits on the upgradient side of the berm located in the River Gut channel near the site. • Sample RGll will be collected from sediment deposits on the upstream side of the sheet piling installed in the River Gut stream channel, downstream of the site. • Samples RG12 through RG17 will be reserved for collecting sedinients from the portions of the River Gut bank adjacent to the Golden Grove Correctional Facility, Meridian Engineering, Virgin Islands Asphalt Products Company and Charlie's Concrete in areas of observed waste material not already targeted by this investigation. • Samples RG18 through RG20 will be collected from the Bethlehem Gut starting at the confluence of OJ o to the River and Bethlehem Guts. One sample will be collected at the confluence, one sample will be to collected 500 feet upstream from the confluence and one sample will be collected 1,000 feet J^ upstream from the confluence. g:\3524i\phaselll\wpadd.DOC Harding Lawson Associates 14 DRAFT The sediment samples will be analyzed for TCL SVOCs, TAL metals, total organic carbon, particle grain size, pH, redox, percent moisture and conductivity. If physical access is possible and health and safety issues are not compromised, one boring will be installed in the River Gut at each of the locations SBRG-1, SBRG-2, and SBRG-3 (Figure 3-4), as requested by the EPA. Two samples from each boring will be analyzed: one from directly above the water table and one from the sample interval with the highest PID reading. If no PID readings are observed, sample intervals will be based on lithology as described in the RI Work Plan. River Gut samples will be analyzed for TCL VOCs, SVOCs and TAL metals. Additional onsite and offsite borings may be installed based on PID field screening results and field observations. Additional samples in the vicinity of the samples collected from borings installed in the River Gut may be collected based on analytical results of the samples collected during this phase. If needed, additional monitoring well(s) may be installed to evaluate the lateral and vertical extent of TCL VOCs, SVOCs, and TAL metals in shallow groundwater beneath the River Gut. Installation of these wells will be based on anal\rtical results of River Gut samples collected from the borings during this phase and will be installed during the next phase, if needed. 3.2 Data Validation Confirmation level laboratory data generated for investigative samples will be validated as discussed in the Work Plan. 3.3 Data Evaluation The data generated during this phase of the RI will be evaluated in conjunction with the data previously generated and reported by HLA (1995, 1996). The data will be evaluated to gain further information on the following: • Onsite and offsite extent of TEX in soil and groundwater in AST Area • Existence of other potential sources in the AST and former drum areas • Extent of dissolved TCL VOCs, SVOCs and TAL Metals in groundwater • Flow direction(s) in the shallow and deep portions of the water-bearing zone • Onsite sediment and River and Bethlehem gut sediment TCL SVOCs and TAL metals concentrations • Onsite and offsite soil TCL VOC, SVOC, and TAL metals concentrations near the site drainage system • Background soil TAL metals concentrations. • Potential applicability of SVE and bioventing as possible remedial alternatives for soil in the AST area • Baseline ecological assessment information concerning potential ecological receptors and exposure pathways associated with the River Gut from the vicinity of the site to the confluence with the to Bethlehem Gut. o to to : o 3:\3524i\phaseIII\wpadd.DOC Harding Lawson Associates 15 DRAFT 3.4 Update/Track ARARs The hst of Applicable or Relevant and Appropriate Requirements (ARARs) will continue to be revised, as needed, throughout completion of the RI activities to take into consideration additional chemical data, site conditions, and potential remedial actions. Further, state and federal registers will continue to be reviewed periodically to identify changes to the ARARs that have already been identified. 3.5 Project Meetings and Reporting 3.5.1 Meetings w i t h EPA One meeting with EPA will be requested following receipt, interpretation, and validation of data generated during the implementation of this RI Work Plan Addendum and prior to preparation of a final Draft Data Summary Report Addendum (DSRA) or preparation of the RI, whichever is appropriate. At that time, the findings will be discussed along with the format for the final report. Additional meetings with EPA may be conducted as needed or upon request. 3.5.2 Monthly Progress Reports Monthly progress reports will continue to be submitted to EPA on the 15 th day of each month(or fhst business day thereafter). The monthly progress reports will be prepared in accordance with the Administrative Order on Consent and the Work Plan. 3.6 Management of Investigation-Derived Waste Investigation-derived waste (IDW) will be managed in accordance with procedures outlined in the Work Plan. OJ o IO to cn ;:\3524i\phasenr\wpadd.DOC Harding Lawson Associates 16 DRAFT 4.0 ANTICIPATED SCHEDULE The following is the anticipated schedule to implement the Phase III RI activities as described in this Work Plan: ACTIVITY Revised Phase III RI Work Plan to EPA DATE June 20, 1997 Implement Revised Phase III Work Plan (assuming two-week review time with authorization from EPA no later than July 7, 1997) Supplemental Data Summary Report or Remedial Investigation Report to EPA July 21, 1997 - September 5, 1997 November 21, 1997 OJ o to to on to g;\35241\phasein\wpadd.DOC Harding Lawson Associates 17 TABLES 302253 B TABLl SUMMARY OF PROPOSED SAMPLES REMEDIAL INVESTIGATION -PHASE III VIRGIN ISLAND CHEMICAL SITE ST.CROIX, U.S. VIRGIN ISLANDS Location AST Area AST Area AST Area Onsite Background AST Area Onsite Onsite Onsite River and Bethlehem Gut Onsite Storm Drain System Onsite Central Storm Drain River Gut N/A - Not applicable MW- Monitoring Well GW- Groundwater G:\work\35241\phaselli\wptb Sample Type Soil grab Soil grab Shelby Tube soil Soil grab GWgrab GW Hydropunch GW grab GWgrab Sediment grab Sediment grab Boring Sample Boring Sample .doc No.of Borings/Monitoring Wells 3 N/A N/A N/A 3 shallow temp.,1 shallow perm. 3 deep 3 deep perm. existing MWs(5) and prod wells (2) N/A N/A "---:,- ^ii"""__"" .7" ^xxyx^ yx"' No. of Samples 8 2 3 3 4 10-ft intervals 3 7 22 - - • • • - • " J • • • - • - - • - " 2 """ Analysis TCL VOCs.SVOCs.TAL metals (HCU) bacteria count.TOC, alkalinity, Iron,ammonia,sulfate,nitrate, nitite,pH, ortho phosphorous grain size, moisture, total organic carbon (TOC), and porosity TAL metals TCL VOCs.SVOCs.TAL metals Onsite portable GC for VOCs; 20% lab confirmation samples TCL VOCs.SVOCs.TAL metals TCL VOCs.SVOCs.TAL metals tcfSVOCsJALmetals, t o e , pH, alkalTnTty " conductivity, redox, percent moisture, particle grain size TCL SVOCs.TAL metals, TOC, pH, alkalinity conductivity, redox, percent moisture, particle grain size TCL VOCs.SVOCs.TAL metals TCL VOCs.SVOCs.TAL metals OJ o to to on »<^ FIGURES 302255 \^-A.\cM-y^i''yy--A'si<Aai,.- \~%y^\^ . Ax^-Axy k j ; - yyBmxyyxsyy^^ ;^>irspiii: S/T V y xyyy y^'.^'y^^ ^ ^ PftlJiii:;1i#"\ \ Harding Lxiwson Associates Engineering and Environmental Services . ~ 131 North Third Slreei 12 FhHodelphic, Pennsyivc.-iio 19106 ':Z-1 215-627-<i505 SITE LOCATION MAP 3 02256 VIRGIN ISLAND CHEMICAL SITE St. Croix, U.S. Virain Isionds FIGURE 1-1 DRAWN WGA JOS NUMBER 35241.5 APPROVED DRAWING NUMBER 35241A0A DATE REVISED DATE 11/5/96 MW-6 X - ; = X SBAST3 to 3 o > • i X X (/) z < > UJ z ? _ l UJ 2 LEGEND PREUMINARY ASSESSMENT SOIL BORING LOCATION MONITORING WELL LOCATION PRODUCTION WELL LOCATION STORMWATER INLET EXISTING ABOVEGROUND STORAGE TANK TANK PAD-FORMER ABOVEGROUND STORAGE TANK LOCATION • Si2US££l ADAPTED FROM SITE MAP. VI CHEMICAL, ST. CROIX. U.S.V.I. BY NUS CORPORATION DOCUMENT 0 2 - 9 1 0 1 - 0 4 - 5 1 . UNDATED Hording Lawson Associotes Engineering ond Environmentol Services 14 Woshington Rood Princeton Juction, New Jersey 08550 609-936-0700 LOCATION OF MONITORING AND PRODUCTION WELLS AND PREUMINARY ASSESSMENT SOIL BORINGS VIRGIN IStAND CHEMICAL SITE St. Croix, U.S. Virgin Islands FIGURE 1-2 OJ o to to on DRAWN JSW/WGA JOa NUMBER 35241.2.12 APPROVED DWG. No. 35241803 DATE 11/7/96 REVISED DATE 6/16/97 SA' 46" - | 7 * 4 4 ' • 4 2 ' 6 4*50' 4 6' 44' 42' 64" c .1 R I B n /•: ./ \ S i i r R i v e n CSIUAKT « T II s I D t & ^ ^.ji^y-y:x>^'-c-<x\ <y\ .^MxymymyxAXxxxyxm/ -m <r'yX}yyyyyyyxy^yyyy^yy^X4^i • 75.^A^ CKANDC PnlNCCSSC GOLDEN ROCK -{^^'''iw'^^x^':••:•••: ••••v^Vriv:^^ CHRISTI*KSTCD OXX^XyA SITE LECENQ BD BEACH DEPOSITS AL ALLUVIUM KL KINGSHILL LIMESTONE X JEALOUSY FORMATION CDI CABBROIC Je DIORITIC INTRUSIVES MEO Mr. EACLE CROUP ORAFT 89S30e Hording Lawson Associates Engineering ond Environmentol Services 131 North Third Street Philodelphia, Pennsylvonio 19106 215-627-4505 DRAWN WGA JOB NUMBER 35241.5 REGIONAL GEOLOGICAL MAP VIRGIN ISLAND CHEMICAL SITE St. Croix, U.S. Virgin Islands FIGURE 1-3 APPROVED DRAWING NUMBER OATE 11/5/95 REVISED DATE Determine horizontal ond verticol extent of e f f e c t e d soils offsite, reloted to the identified onsite s o u r c e oreo a s s o c i a t e d with the AST f o r m . Secure occess to offsite property for soil boring ond well installation -®—• Select locotlon for odditionol offsite boring rodiolly o u t w o r d f r o m this locotion. Collect soil s a m p l e s f r o m boring at selected location Field screen s o m p l e s for organic vapors using PID Submit two somples f r o m each boring for loborotory onolysis Assess l o c o t i o n ( s ) for odditionol offsite a n d onsite soil borings to define extent of I m p o c t e d soil. Begin Temporory Well sompling p r o g r a m to ossess horizontal extent of e f f e c t e d groundwoter neor AST area. Soil Somple Ooto collection tosk c o m p l e t e d . Proceed to Temporary Well Sampling P r o g r o m Select odditionol location 5 0 feet rodiolly o u t w o r d f r o m boring s o m p l e d Mobilize to plonned location for Temporary Well. Advonce boring to 15 ft below woter toble ond install Temporory Well. Collect groundwater sample. Evoluote offsite ond onsite water level d o t o collected during preliminory Phose III site a s s e s s m e n t activities. If doto suggest possibility ofN offsite source oreo, confer with EPA Select locotion for third deep onsite m o n i t o r i n g well Install three deep onsite m o n i t o r i n g wells Install shollow m o n i t o r i n g well ot furthest downgradient locotion s o m p l e d Existence of other potential ^sources In AST oreo a n d f o r m e r ^ d r u m oreos. Collect c o m p l e t e r o u n d of g r o u n d w a t e r s o m p l e s Evoluote onolylicol soil results f r o m AST oreo ond f o r m e r d r u m oreos collected during preliminory Phose I site ossessment octivilies Prepare Data S u m m a r y Report^ or Remediol Investigation Report y If doto suggest possibility of ' odditionol soil b o r i n g s / m o n i t o r i n g well(s)) confer with EPA 6S230e Harding Lawson Associates Engineering and Environmental Services 14 Washington Roud Princeton Juction, New Jersey 08550 6 0 9 - 9 3 6 - 0 7 0 0 FLOW CHART V I R G I N I S L A N D C H E M I C A L SIT S t . C r o i x , U . S . V i r g i n I s l a n d s PRAFT FIGURE 2-1 DRAWN WGA JOB NUMBER 3 5 2 4 1 . 7 . 2 APPROVED DWG. No. 3 5 2 4 1 B 0 6 DATE 1 / 2 0 / 9 7 REVISED DATE 6 / 1 6 / 9 7 DRAFT Tl ^1 I ^1 \LJ LJ SBB9 + 0 ^J;12JP®SBBIO + © SBBUI SBAST1 © SBAST2 SBB2 MW-1 S B B | 1 3 © ^ B B I ' I - I I ^1 LJ sSBB6 SBB8© mSBAST3 rn^rn r i r i 121 I ^1 L J L J ® SBB^r©'^ © ®' SBB7 mSBB5 ^ ^ ABOVEGROUND TANK FARM ®SBB4 ©SBB16 SBB3 I ^1 I :el I •ij I •ij LJ LJ © SBAST4 ri ri I C:l I » l I • ^ l I ^ 1 LJ LJ SBEl® EARTHEN BERM WALL 30 60 90 ft. FOR ILLUSTRATION PURPOSES ONLY 092Soe ^SBB15 RAMP LEGEND • PROPOSED TEMPORARY WELL LOCATION PROPOSED SOIL BORING LOCATION PROPOSED DEEP MONITORING WELL LOCATION © CZ) CID PREVIOUS SOIL BORING LOCATION MONITORING WELL LOCATION EXISTING ABOVEGROUND STORAGE TANK TANK PAD-FORMER ABOVEGROUND STORAGE TANK LOCATION Harding Lawson Associates Engineering and Environmentol Services 14 Woshington Rood Princeton Junction, New Jersey 08550 609-935-0700 DRAWN WGA JOB NUMBER 35241.5 PROPOSED SAMPLING LOCATIONS VIRGIN IStAND CHEMICAL SITE St. Croix. U.S. Virgin Isionds FIGURE 3-1 APPROVED DRAWING NUMBER 35241A11 OATE 11/7/96 REVISED DATE 6/20/97 LOCKING PROTECTIVE CASING GROUND SURFACE A A A A A A A A CEMENT CEMENT BENTONITE • SLURRY 8" STEEL CASING V RLTER PACK SAND 4 " WELL SCREEN 8" BOREHOLE z m \A A A A A A A A SL GROUT 12" BOREHOLE WATER TABLE UJ UJ m 4" WELL CASING BENTONITE SEAL (2 FEET MIN.) UJ (AJ O to H Harding Lawson Associates Engineering ond Environmental Services 14 Woshington Rood Princeton Juction. New Jersey 609-936-0700 DOUBLE-CASED MONITORING WELL CONSTRUCTION DIAGRAM VIRGIN ISLAND St. Croix, U.S. DRAWN JSW/WGA JOB NUMBER .35241.5 APPROVED CHEMICAL SITE Virgin Islands FIGURE 3-2 DRAWING NUMBER 35241A07 DATE 11/7/96 REVISED OATE GOLDEN Ca«)VE ADULT CORRECTIONAL FAOUTY # Y LEGEND »«.«••.<-••«,* A» ««»A,>.»_>.>_> TREE LINE BUILDING STREAM ROAD EXPECTED LOCATION OF OFFSTE WELLS CO o IO to o^ to FOR ILLUSTRATION PURPOSES ONLY Harding Lawson Associates Engineering and Environmentol Services 14 Washington Rood Princeton Juction. New Jersey 08550 609-936-0700 _ APPROXIMATE LOCATION OF OFFSITE PRODUCTION WELLS VIRGIN ISLAND CHEMICAL SITE St. Croix, U.S. Virgin Islands ncuRE 3-3 DRAWN JSW/WGA JOB NUMBER 35241.5 APPROVED DWG. No. ."^S9/11P1 1 OATE 1 / o n / m REVISED OATE LEGEND DRAFT PROPOSED SEDIMENT SAMPLE LOCATION PROPOSED BACKGROUND SOIL SAMPLE LOCATION PROPOSED SEDIMENT AND SOIL BORING LOCATION PROPOSED SOIL BORING LOCATION MONITORING WELL LOCATION PRODUCTION WELL LOCATION STORMWATER INLET EXISTING ABOVEGROUND STORAGE TANK TANK PAD-FORMER ABOVEGROUND STORAGE TANK LOCATION 240 ft. NOTES: 1) SAMPLES RG-2 THROUGH RG-17 WILL BE FIELD LOCATED IN AREAS OF OBSERVED NON-SITE RELATED MATERIAL ADJACENT TO COMMERCIAL FACILITIES IN THE VICINITY OF THE SUBJECT SITE AND THE RIVER GUT (SEE FIGURE 5 - 5 } 2) SAMPLES RG-18 THROUGH RG-20 WILL BE COLLECTED FROM BETHLEHEM GUT EVERY 500 FEET UPSTREAM FROM CONFLUENCE WITH RIVER GUT (SEE FIGURE 5-3) SQURCEl SITE MAP, VI CHEMICAL, ST CROIX, U.S.V.I. BY NUS CORPORATION DOCUMENT 02-9101-04-51, UNDATED AND AERIAL PHOTOGRAPHS O to to o^ CO RG-11 Harding Lawson Associates Engineering ond Environmental Services 14 Woshington Rood Princeton Juction, New Jersey 08550 609-936-0700 PROPOSED SAMPUNG LOCATIONS ONSITE AND RIVER GUT VIRGIN ISLAND CHEMICAL SITE St. Croix, U.S. Virgin Islands FIGURE 3-4 DRAWN WGA JOB NUMBER 35241.5 APPROVED DWG. No. 35241B10 DATE l / 2 0 / q 7 REVISED DATE p. / o n / Q 7 APPENDIX A CONTAINERS, PRESERVATION, PACKAGING, AND SHIPPING REQUIREMENTS 302264 Appendix A. Containers, Preservation, Packaging, and Sliipping Requirements island Cliemical Company St. Croix, U.S. Virgin Islands to o to to CTl cn Analysis Containers Groundwater Organic Analyses TCL VOCs TCL SVOs Pyridine TCL Pesticides and PCBs Tlirofi 40-ml glnss vinls with Teflon septum-lined caps Two 1-liter amber glass bottles with Teflon -lined caps Two 1-liter aniher glass bottles with Teflon -lined caps Two 1-liter amber glass bottles with Teflon -lined caps Groundwater Inorganic Analyses TAL metals (unfiltered) TAL metals (filtered) Cyanide One 1-liter polyethylene bottle One 1-liter polyethylene bottle One 1-liter polyethylene bottle Preservation 1:1 IICl lo pll <2, cool to 4"C in dark storage Cool to 4°C in dark storage Cool to 4"C in (lark storage Cool to 4°C, NajSzOj HNOgtopH <2.0 HNO3 to pH <2.0 NaOH to pH >12, cool to 4°C Technical Holding Time' 14 day.s Extract within 7 days, analyze within 40 days after extraction Extract within 7 days. analyze within 40 days after extraction Extract within 7 days, analyze within 40 days after extraction 6 months, except Hg - 28 days 6 months, except Hg - 28 days 14 days Volume of Container Fill comphitely. no air bubbles Fill 90% full Fill 90% full Fill 90% Fill 90% Fill 90% Fill 90% Shipping Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Normal Packaging Bubble pack B>ibble pack Bubble pack Bubble pack Bubble pack Bubble pack Bubble pack Soil Organic Analyses TCL VOCs One 120-ml vial with Teflon™-septa lined lid Cool to 4°C in dark 10 days storage TCL SVOs Two 16-oz. amber glass jars Cool to 4°C in dark Extract within 7 days Fill completely Fill 90% and Pyridine with Teflon -lined lid storage and analyze within 40 days after extraction Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Bubble pack Bubble pack Revised May 17, 1997 F:\35241\WP\T001.DOC Harding Lawson Associates Packa Appendix A. Containers, Preservation, Packaging, and Shipping Requirements island Chemical Company St. Croix, U.S. Virgin Islands CO o to to Analysis TCL Pesticides and PCBs Containers One 4-oz wide-mouth glass jar with Tenon™-lined lid Soil Inorganic Analyses TAL Metals Cyanide Nitrate/Nitrit e Sulfate Sulfide Iron (total) Alkalinity Ammonia Ortho phosphorus Vfay 17, 1997 \WP\T001.DOC One 8-oz wide-mouth glass jar with Tenon™-lined lid To be analyzed using material from metals sample One 32-oz glass bottle* One 32-OZ glass bottle* One 32-OZ glass bottle* One 8-oz wide-mouth glass jar with Teflon™-lined lid One 32-oz glass bottle* One 32-OZ glass bottle* One 32-OZ glass bottle* Preservation Cool to 4°C Cool to 4°C Cool to 4°C Cool to 4°C Cool to 4°C Cool to 4°C Cool to 4°C Cool to 4°C Cool to 4°C Cool to 4°C Technical Holding Time' Extract within 7 days and analyze within 40 days after extraction 6 months, except Hg - 28 days 14 days 28 days 28 days 7 days 6 months 14 days 28 days 48-hours Harding Lawson Associates Volume of Container Fill 90% Fill 90% Fill 90% Fill 90% Fill 90%) Fill 90% Fill 90% Fill 90%. Fill 90%) Fill 90% Shipping Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Normal Packaging Bubble pack Bubble pack Bubble pack Bubble pack Bubble pack Bubble pack Bubble pack Bubble pack Bubble pack Bubble pack CO o to to o\ Packa Appendix A. Containers, Preservation, Packaging, and Shipping Requirements Island Chemical Company St. Croix, U.S. Virgin Islands Analysis Containers Preservation Technical Holding Time Volume of Container Shipping Normal Packaging pH One 32-OZ glass bottle Cool to 4°C As soon as possible Fill 90% Total Organic Shelhy Tube Carlion Moisture Shelby Tulte Grain size Shelby Tube Porosity Shelby Tube HCU bacteria 500-ml Glass Count Total plate 500-ml Glass bacteria count None None None None Cool to 4°C Cool to 4°C 28 (hiys None Set None Set 24-hours or as soon as possible 24-hours or as soon as possible Fill 90% As soon as possihle Fill 90% Fill 90% Fill 90% Fill 90% Fill 90% Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- hours of collection by overnight carrier Ship within 24- houTS of collection by overnight carrier Bubble pack Bubble pack Bubble pack Bubble pack Bubble pack Bubble pack Bubble pack Revised May 17, 1997 F:\35241\WP\T001.DOC Harding Lawson Associates CO o to to a\ 00 Notes: Parameters and detection limits will be consistent with methods listed in Tables Cl-2 through Cl-7 of the Quality Assurance Project Plan Sample containers will be prepared according to OSWER Directive No. 9240-05-05A, "Specification and Guidance for Obtaining Contaminant-Free Sample Containers, (December 1992)" or certified clean containers (e.g., I-Chem 300 series) will be used. Certificates of analysis verifying sample container cleanliness will be retained and available for review by USEPA. * There are no SW-846, Test Methods for Evaluating Solid Waste" protocols for nitrite, alkalinity, ammonia, or ortho-phosphate. We have proposed using EPA Chemical Analysis of Waters and Waste Methods. Because these methods were written for liquids, not solids, minor modifications will be required. Although nitrite can be analyzed by method SW 9200 we are not aware of any laboratories that still run this method. We propose analyzing nitrate similarly to nitrite. The following are brief descriptions of method modifications for each parameter: 1. Alkalinity - 10 grams of sample aliquot is leached with 100 ml of DI water for 1 hour. Decant 50 ml of leachate. Titrate as prescribed in method. 2. Ammonia - Distill 2 grams of sample to a final volume of 100 ml. Analyze by colorimetric autoanalyzer as prescribed in method. 3. Nitrate - 10 grams of sample aliquot is leached with 100 ml of DI water for 1 hour. Analyze by colorimetric autoanalyzer as prescribed in method. 4. Nitrite - 10 grams of sample aliquot is leached with 100 ml of DI water for 1 hour. Analyze by colorimetric autoanalyzer as prescribed in method, ortho-phosphate -10 grams of sample aliquot is leached with 100 ml of DI water for 1 hour. Analyze by colorimetric autoanalyzer as prescribed in method. ' The time of sample collection to extraction/analysis. G gram < less than HNO3 nitric acid HCl hydrochloric acid oz. ounce ml milliliter VOCs volatile organic compounds SVOs semivolatile organic compounds > H2S04 NaOH TAL greater than sulfuric acid sodium hydroxide Target Analyte List °C Hg NajSjOj TCL degree Celsius mercury Sodium thiosulfate Target Compound List Revised May 17, 1997 F:\3524i\WP\T00i.DOC Harding Lawson Associates APPENDIX B FIELD SAMPLING PLAN 302269 APPENDIX B CONTENTS 1.0 INTRODUCTION 1 2.0 FIELD INVESTIGATION PROGRAM 2 2.1 Stream Sediment Sampling 2 2.1.1 Sediment Sampling When Stream is Dry 2 2.1.2 Sediment Sampling When Stream is Flowing 2 2.2 Shelby Tube Soil Sample Collection 3 2.3 Hydropunch® Groundwater Sampling 3 2.4 Mud Rotary Drilling Methods 4 2.5 Monitoring Well Installation 5 2.5.1 Double-Cased Well Construction 5 2.5.2 Temporary Monitoring Well Construction 6 2.6 Low Flow Purging and Groundwater Sampling 7 2.7 Onsite VOC Analysis by Gas Chromatograph 10 2.8 Aquifer Slug Testing 11 CO o to to > j o F:\3524i\WP\APPENA.DOC Harding Lawson Associates 1.0 INTRODUCTION Harding Lawson Associates (HLA) has prepared this addendum to the EPA-approved Remedial Investigation Work Plan (RIWP) - Sampling and Analysis Plan (SAP) (HLA, 1994) on behalf of Island Chemical Company, Inc. (ICC). This SAP Addendum will be included in the RIWP as Appendix AD in support of the RIWP Addendum (RIWPA) and responds to requirements set forth in the National Contingency Plan. The RIWPA includes the following activities which were not specified in the original RIWP: Collection of stream sediment samples Collection of undisturbed soil samples using a Shelby tube sampling device Collection of groundwater samples using a Hydropunch® sampling device Onsite analysis of groundwater samples using a portable gas chromatograph (GC) Installation of soil borings and monitoring wells using mud-rotary drilling methods Installation of temporary monitoring wells Installation of double-cased monitoring wells Collection of groundwater samples using low-flow groundwater sampling procedures Estimation of hydraulic properties of the shallow aquifer using slug testing methods Procedures for additional activities planned during the implementation of the RIWPA are described in the SAP, Appendix A of the original RIWP. CO o IO IO -J F:\3524i\WPvAPPENA.DOC Harding Lawson Associates 2.0 FIELD INVESTIGATION PROGRAM Specific field procedures to perform the activities identified in Section 1.0 above are presented in this addendum. 2.1 Stream Sediment Sampling Efforts will be made to collect stream sediment samples when River Gut is not flowing. Section 2.1.1, presents the sampling procedures to be followed if the stream is dry. However, if it is necessary to collect sediment samples when River Gut is flowing, HLA will follow the sampling procedures described in Section 2.1.2. 2.1.1 Sediment Sampling When Stream is Dry 1. The proposed sample locations shown in Figure 3-4 of the RIWPA will be located by measuring from fixed visible reference points using a tape measure. 2. The area vnthin roughly 10 to 20 feet of the proposed sample locations will be inspected visually to determine qualitatively the area of greatest sediment deposition. This area will be selected as the final sampling location. 3. A field-decontaminated, stainless steel trowel will be used to collect the sediment sample from the dry stream bed at the final sampling location. The trowel will be decontaminated before use following the procedures specified in Section A2.4.2.2 of the RIWP. 4. The sediment sample will be transferred directly to laboratory-prepared sample containers which will then be sealed, labeled as described in Section A2.10.1 ofthe RIWP, and placed directly into a cooler with ice (approximately 4°C). 5. The final sample location will be marked and photographed to show its location with respect to fixed references. 6. The distance from each sampling point will be measured with respect to at least three fixed references and recorded to allow future relocation of the sample. 2.1.2 Sediment Sampling When Stream is Flowing If possible, sediment sampling wall be postponed until the stream is dry. If this is not practical, the stream sediments will be sampled using the following procedures: 1. Stream flow will be evaluated to determine if the stream can be entered safely. 2. Beginning at the furthest downstream location, HLA personnel will enter the stream at a location dovimstream of the proposed sampling location. All sample locations will be approached from the downstream direction to avoid disturbing upstream sediments that might be carried to downstream locations not yet sampled. 3. The proposed and final sample locations will be determined as described in Steps 1 and 2 of Section 2.1.1. o 4. A field-decontaminated Eckman Dredge sampler will be used to collect the sediment samples at f^ each location. ^ lo F:\3524i\WPVAPPENA.DOC Harding Lawson Associates 5. The sediment sample will be transferred from the dredge to laboratory-prepared sample containers using a field-decontaminated stainless steel trowel. The sample container will then be sealed, labeled as described in Section A2.10.1 of the RIWP, and placed directly into a cooler with ice (approximately 4°C). 6. The sample location will be photographed and recorded as described in Steps 5 and 6 of Section 2.1.1. 2.2 Shelby T u b e Soil S a m p l e Collection Soil samples will be coUected from fine-grained material using a Shelby tube sampling device. The Shelby tubes will be approximately 2 feet long, 3 inches in diameter and constructed of stainless steel tubing or equivalent materials. The upper end of the Shelby tube will be fastened to a check value that helps hold the sample in place as it is being withdrawn. Field documentation and equipment decontamination will be conducted as specified in the RIWP. The following procedures will be used to obtain undisturbed soil samples using the Shelby tube: 1. The boring will be advanced to the top of the interval to be sampled. 2. The drill bit and drilling rods will be removed from the boring and a field decontaminated Shelby tube sampler will attached to the drill rod assembly and lowered to the bottom of the boring. 3. The Shelby tube will then be pushed to the required depth, if possible. The Shelby tube will be advanced by the application of hydraulic pressure from the drill rig to the drill rod assembly. 4. Once the Shelby tube has been advanced to the final depth, activities will be halted for several minutes to allow the soil sample to equilibrate within the Shelby tube. The drill rod assembly will then be rotated 1/4 to 1/2 turn to separate the sample from the underlying soils. 5. The rod assembly with the Shelby tube sampler will then be withdrawn from the boring. 6. The Shelby tube will be disconnected from the drilling rod assembly and approximately 1 to 2 inches of soil will be removed from the bottom of the tube after it is recovered. 7. Both ends of the sample will then be sealed with several inches of paraffin, liquefied by heating. Care will be taken to completely seal the ends of the soil sample to prevent moisture loss 8. Once the paraffin has dried, any void space in the top of the tube will be filled tightly with a packing material, such as crumpled paper. Each end of the tube will be secured with a plastic end cap taped in place. 9. The outside of the Shelby tube will be labeled to indicate the sample identification, date of sampling, and top of the sample. Care will be taken to keep the sample in an upright position during handling. Instructions will be provided to the carrier to ship the samples in an upright position. 2.3 Hydropunch® G r o u n d w a t e r S a m p l i n g Groundwater samples will be collected from the pilot boring for deep monitoring well MW-6 in the Above-ground Storage Tank (AST) area using a Hydropunch® sampling device. The Hydropunch® is a , ^^ 5-foot long sampling device that consists of a drive point; 1-inch diameter, 4-foot long disposable o screen; and a retractable stainless steel sleeve. The screen is made of poly vinyl chloride (PVC) or polypropylene. The Hydropunch® will be used to collect groundwater samples from selected depth intervals using the following procedures: w to lo F:\3524i\WP\APPENA.DOC Harding Lawson Associates 1. Once the boring has been advanced to the selected depth by the driller, the drill bit and rods will be removed. 2. The Hydropunch® sampler, equipped with an unused, disposable screen, will be attached to the drill rods and set at the bottom of the boring. 3. The Hydropunch® sampler will be driven into the formation using a 140- or 300-pound hammer. The Hydropunch® sampler will be driven 4-feet into the formation or until refusal is encountered. A total of 100 blows over a six-inch interval will be considered refusal. The number of blows and distance driven will be recorded. 4. If the Hydropunch® sampler is driven less than 1-foot before refusal is encountered, no sample will be collected, the boring wiU be advanced 5 feet, and a second attempt will be made to drive the Hydropunch® sampler into the formation. 5. If the Hydropunch® sampler is driven 1-foot or more, the sleeve will be retracted approximately one-half the distance that the sampling device was driven (i.e., retract the sleeve 2 feet if the sampler is driven 4 feet), exposing the disposable screen to the formation. Sufficient time will be given to allow groundwater to flow into the Hydropunch®. An electronic depth-to-water probe will be lowered inside the drill rods and Hydropunch® to monitor groundwater recharge. 6. Groundwater will be allowed to equilibrate in the Hydropunch® for a minimum of 30 minutes or until the water level inside the drill rods has reached 90 percent of the distance from the water table to the bottom of the sampler. 7. A field-decontaminated 1/2-inch diameter Teflon™ bailer will be lowered on Teflon™-coated stainless steel cable through the Hydropunch® rods to collect a groundwater sample from the screened interval. Prior to use at each sampling interval, the Teflon™ bailer and cable will be decontaminated following the procedures described in Section A2.4.2.2. The bailer holds approximately 20 ml. Therefor the bailer will be lowered several times at each interval to completely fill the 40 ml vial with no headspace. 8. The color, qualitative turbidity and other pertinent observations of the groundwater sample vrill be noted and recorded in the field book. 9. Approximately 20 milliliters (mL) of groundwater sample will be poured directly into an unpreserved 40-mL glass vial, and submitted for onsite analysis of toluene, ethylbenzene, and xylenes by the field GC as described in Section 2.7. 10. Co-located groundwater samples will be obtained for laboratory analysis at a rate of one sample for every ten screening samples. HLA will submit a minimum of one groundwater sample for laboratory analysis collected from zones displaying no detected volatile organic compounds (VOCs) by field screening. The co-located samples will be collected in 40-mL vials prepared by the laboratory, preserved in the field and submitted to the laboratory for analysis of Target Compound List (TCL) VOCs by Contract Laboratory Program (CLP) methodologies as specified in the RIWP. The co-located samples will be collected, preserved and handled as described in steps 23 through 27 of Section A2.8 of the RIWP. 2.4 Mud Rotary Drilling Methods Mud-rotary drilling methods will be utilized to advance the deep boring for the double-cased well in the AST area. Mud-rotary drilling techniques are described below. Double cased well construction is i to described in Section 2.5.1.1 , '^ F:\3524i\WP\APPENA.DOC Harding Lawson Associates o 1. Prior to set up, the drill rig and equipment will be decontaminated by steam cleaning and/or a potable water wash as described in Section A2.4.2 of the SAP. 2. The drill rig and mud tub will be placed at the selected drilling location. The mud tub will contain baffles to enhance settlement of solids entrained in the drilling fluid. 3. A tri-cone roller or wing bit will be attached to the drill rods. 4. The mud tub will be partially filled with potable water. The potable water will be obtained from the driller's office, consistent with previous work on this project. The driller v\nll then circulate the water through the drilling tools and mud tub adding bentonite-based drilling mud as necessary to create a viscous drilling fluid. The amount of bentonite added and the viscosity of the fluid will be established in the field at the discretion of the driller. 5. Once the driller is satisfied that the drilling fluid is of adequate consistency, the driller will advance the borehole to the desired depth. During drilling, the drilling fluid will be pumped dovim through the drilling rods. The fluid will circulate to the ground surface by rising in the annular space of the boring. Cuttings from the boring will be entrained with the rising fluid and will be separated to the extent possible in the mud tub at the surface. The viscosity of the fluid may be altered during drilling activities at the driller's discretion by adding water or mud. 6. During drilling, solids will be removed from the mud tub as needed and containerized onsite in 55- gallon drums. Drummed investigation-derived waste will be staged onsite until proper disposal arrangements are completed. 7. Soil samples will be collected and logged as described in Section A2.4.3 of the SAP. 8. The volume of drilling fluid lost to the formation will be monitored during drilling and recorded on the field boring log. 2.5 Monitoring Well Installation Drilling methods for the installation of monitoring wells will be selected based on field conditions and the anticipated depth of the borehole. It is anticipated that the borings for the shallow soil zone will be drilled using hollow-stem augers and that mud-rotary drilling methods will be necessary for the installation of deeper wells. Mud-rotary drilling methods may also be necessary for installation of shallow monitoring wells if problems with auguring are encountered. The procedures described below will be used to construct the proposed double-cased and temporary groundwater monitoring well. Procedures for well development and for construction of single-cased monitoring wells are described in Section A2.5 of the RIWP. Well construction details will be recorded by an HLA geologist. Equipment decontamination will be conducted as described in Section A2.4.2 of the RIWP. 2.5.1 Double-Cased Well Construction The foUowing procedures wiU be implemented during installation of the double-cased monitoring well at the site: 2. The driller will advance a 12-inch diameter boring to approximately 5 feet above the predicted water table depth using mud-rotary drilling techniques as described in Section 2.4. The approximate depth to the water table will be estimated before drilling activities begin based on F:\3524i\WPVAPPENA.DOC Harding Lawson Associates to o Prior to set up, the drill rig and equipment will be decontaminated by steam cleaning and/or a potable water wash as described in Section A2.4.2 of the SAP. . to to cn groundwater elevations measured at nearby monitoring wells. 3. Beginning at this depth, the driller will collect soil samples using a split-spoon sampling device as described in Section A2.4.3. Split-spoon samples will be collected continuously until the water table is encountered. An HLA geologist will examine the soil samples to determine the level of the water table. 4. The driller -will then advance the boring to 5 feet below the water table. 5. An 8-inch diameter steel casing with welded or threaded joints will be lowered to the bottom of the boring and centered. The casing will be long enough to extend to the ground surface and will be seated using a hammer assembly. 6. A Portland cement/bentonite grout will be emplaced from the bottom up in the annulus around the casing using a tremmy pipe. The grout will be pumped into the boring until it displaces the drilling fluid and reaches the ground surface. 7. After the grout has set for at least 24 hours, the drilling fluid inside the casing will be circulated thoroughly with potable water until visible drilling fluids have been removed and clear water remains inside the casing. 8. Drilling equipment will be decontaminated and the drilling fluid will be replaced. If possible, water will be used instead of mud to drill the remainder of the boring. If mud is necessary, efforts will be made to minimize the amount of mud added to the drilling fluid. 9. An 8-inch diameter boring will be advanced through the casing to the final well depth. Sampling will be performed as appropriate following procedures described in other sections of the RIWP. 10. The remainder of the well construction methods will be the same as those used to construct single- cased monitoring wells as described in Section A2.5.1 of the RIWP. Figure 3-2 depicts typical double-cased monitoring well construction. Equipment decontamination will be conducted as described in Section A2.4.2 ofthe RIWP. 2.5.2 Temporary Monitoring Well Construction Temporary groundwater monitoring wells will be installed following the methods described in Section A2.5.1 for single-cased monitoring wells. In general, the following procedures will be used unless field conditions require modifications: 1. Prior to set up, the drill rig and equipment will be decontaminated by steam cleaning and/or a potable water wash as described in Section A2.4.2 of the SAP. 2. The driller will advance a 6.5-inch diameter boring to approximately 5 feet above the predicted water table depth using hollow-stem auger drilling techniques as described in Section A2.4.1. The approximate depth to the water table will be estimated before drilling activities begin based on groundwater elevations measured at nearby monitoring wells. 3. Beginning at this depth, the driller will collect soil samples using a split-spoon sampling device as described in Section A2.4.3. Split-spoon samples will be coUected continuously until the water table is encountered. An HLA geologist will examine the soil samples to determine the level of the water table. 4. The driller will then advance the boring to between 5 and 6 feet below the water table. a\ 5. The temporary monitoring well will be constructed of 2-inch diameter, schedule 40, flush-joint, threaded PVC with a 10-foot section of 0.020-inch factory-slotted screen. The PVC well will be F:\3524i\VVP\APPENA.DOC Harding Lawson Associates 6 to o to to lowered into the boring and suspended such that approximately 5 feet of screen is above and below the water table. If the boring is drilled with hollow-stem augers, the well will be constructed inside the augurs before they are removed. If the boring is drilled using rotary drilling techniques, the drilling tools will be removed before the well is constructed. 6. The boring will be allowed to collapse naturally around the well screen. If necessary, a small amount of filter sand will be poured into the boring to bring the bottom of the boring to the appropriate depth. If addition of sand is necessary, it will be poured slowly to avoid bridging. 7. Plastic sheeting will be taped securely around the riser pipe approximately one foot above grade and spread out to form a skirt that extends radially at least 18 inches from the center of the well. The edges of the skirt will be covered and weighted prevent runoff frorn entering the well annulus. 8. The temporary well will be capped with a locking, expandable plug. 9. If the well boring is advanced using mud rotary drilling techniques, the well will be initially developed by pumping and surging with potable water to remove the visible drilling fluid. After a minimum of 48-hours following the initial development, the temporary well will be developed agcdn using the same techniques. If the well is installed using hollow-stem augers or water rotary methods, only one phase of well development will be performed. Equipment decontamination will be conducted as described in Section A2.4.2 of the RIWP. If the decision is made to complete a temporary well as a permanent monitoring well, the 2-inch casing and screen will be removed, the boring will be reamed and the well constructed as described in Section A2.5 of the RIWP. If the well is not converted to a permanent monitoring well, the temporary well will be abandoned by removing the 2-inch casing and screen and backfilling the boring with powdered bentonite. 2.6 Low Flow Purging a n d G r o u n d w a t e r Sampling Groundwater monitoring wells will be purged and sampled using low-flow groundwater sampling procedures as described in EPA's Groundwater Issue (EPA, April 1996). Groundwater sampling procedures will generally follow the steps described in Section A2.8. Field documentation, sampling preparation, and sampling apparatus decontamination procedures will be consistent with the RIWP. The low-flow groundwater sampling procedures are described below: BEFORE ENTERING THE nELD • Project objectives and quality assurance procedures, sampling locations, sampling procedures, preservation, packaging and shipping requirements, and analytical parameters will be reviewed with field personnel. • Previous water level measurements for each well, if available, will be reviewed before leaving for the site, and a summary of previous water level data will be taken to the field. • Health and safety procedures will be reviewed with all personnel. • A list of wells to be sampled and analyses to be performed will be prepared and transmitted to the ^^ laboratory. O to • All field equipment will be tested to ensure that it is operating properly. Because of the remote .^ location of the site, duplicate instruments will be mobilized to limit down time due to possible *>J equipment malfunction. F:\3524i\WP\APPENA.DOC Harding Lawson Associates • The laboratory will provide clean glassware required to collect the samples. The glassware will be cleaned in accordance with OSWER Directive 9240.0-05A. The glassware will include required preservatives and a list of which preservatives correspond to each analyte will be included with the glassware. The laboratory will provide sufficient glassware and/or samples for trip blanks, field blanks, and duplicate samples to be collected at the frequency described in the Quality Assurance Project Plan (QAPP) presented in Appendix C of the RIWP. IN THE HELD • Sampling crews will receive labeled sample kits from the field manager and will confirm that the kits contain appropriate sample botfles, preservatives, filter pumps, ice, sample labels, chain-of- custody records, and well construction information. • Before purging or sampling each well, equipment will be decontaminated. Decontamination of pumps will include rinsing the pump and tubing with soapy water and deionized water before use. • The well number, date, pertinent observations (e.g., weather, well condition), casing diameter, screened interval, and field instiument identifications will be recorded on groundwater sampling forms (Appendix AA). • Monitoring instruments vdll be calibrated against known standards before making well measurements (generally calibrated once per day). Calibration will be recorded on field calibration data sheets as included in Appendix AA. • The well will be uncapped from the. upwind direction and a photo-ionization detector (PID) or flame-ionization detector (FID) will be used to record relative organic vapor concentrations upwind from the well, at the top of the casing and within the well casing. Procedures for use of the FID or PID will be consistent with the manufacturer's manual, which may vary slightly from model to model. The manual will be kept onsite at all times during equipment use. • Depth to water will be measured using an electronic interface probe. The probe will be lowered into the well until a contact with the water surface is indicated by an electionic signal. • The tape will be marked or held at the measuring point. • The electric tape will be checked to ensure that it has not been cut by a sharp casing edge eifter it is placed in and removed from the well. • The depth to water will be measured to an accuracy of 0.01 foot. • The probe vrill then be lowered below the groundwater and raised until the signal indicates that the probe is above the water table. The depth to water will be measured again as described in steps 7 through 9 above. • The groundwater elevation relative to mean sea level (MSL) will be determined by subtracting the depth to water from the surveyed top of casing elevation (measuring point). Measurements at each well will be taken at the marked survey point on the inner casing and will be repeated until two consecutive measurements are obtained that agree within ±0.02 foot. Water level measurements will be recorded on water level measurement forms (Appendix AA). Well identification, date, time, depth in feet to groundwater and remarks relevant to groundwater level measurements will be LO noted. Previous water level measurements for the well will be checked. If the difference between o the current water level and the previous water level is greater than one foot, the water level will be , i^ remeasured. i ^ 00 F:\3524i\WP\APPENA.DOC Harding Lawson Associates • The sample (pump intake) depth will be determined before sampling equipment is introduced into the well. In the wells in which the water level is above the top of the screen, the pump intake will be set at the middle of the screened interval. If the well is screened across the water table, the pump intake will be set at the mid-point between the groundwater level and the bottom of the well. Every effort will be made to avoid placing the pump intake or water level indicator within two feet of the bottom of the well. • A field-decontaminated 2-inch diameter stainless steel submersible electiicai sampling pump (Grunfos Redi-Flo II or equivalent) and dedicated 1/2-inch diameter Teflon -lined tubing (tubing inner diameter will be between 1/4 and 3/8 of an inch) will be used to purge and sample the well. To minimize excessive mixing of the standing water column in the riser v^dth the water in the screened interval and to minimize the disturbance of solids which may have settled on the bottom, the pump and tubing will be carefully and slowly lowered to the pre-determined installation depth. • Depth to water will be measured after the pump has been installed to evaluate the effect of water displacement. Prior to purging, a final depth-to-water measurement will be recorded. At the start of purging, the flow rate will be monitored until a rate between 0.1 and 0.5 liters per minute (Lpm) is obtained. The flow rate will be measured using a volume-calibrated container and a watch. The water level will be monitored periodically as a guide to flow rate adjustment. Efforts will be made to keep drawdown to less than 0.1 meters (0.328 feet) during purging. If this minimal drawdown cannot be sustained, the water level will be monitored until a constant drawdown is achieved. • If drawdov^m does not stabilize at the minimum purge rate of 0.1 Lpm, the pump will be shut dowm periodically during purging to allow the well to recharge so that the water level does not fall below the pump during purging. • After the drawdown has stabilized, HLA will measure specific conductivity, temperature, pH, reduction/oxidation (Redox) potential, dissolved oxygen (DO), and turbidity using an in-line flow- through cell approximately every three to five minutes. Field measurements will be performed as described in Section A4.0 of the SAP. • Purging will continue until the following five parameters measured in the field have stabilized for three successive readings. Readings will be considered stabilized based on the following criteria set forth by EPA [Groundwater Issue, April 1996): - Conductivity ± 3 percent - pH ± 0.1 Standard Units - Redox potential ± 10 millivolts - DO ±10 percent Turbidity ±10 percent Temperature will be monitored but will not be used to establish stabilization. • Data on method and amount of water purged will be recorded on a groundwater sampling form (Appendix AA). • Water purged from the monitoring wells will be collected and stored at the site in properly labeled 55-gallon drums. The information specified on the drum label(s) will include, at a minimum, the date and well number(s) corresponding to the wells from which the water was removed. The water Ui will be stored until final disposal arrangements are completed. 5? to • Sample collection will begin immediately after the five parameters noted above have stabilized. ^ VO • During sample collection, the flow rate will remain the same as the established purge rate. F:\3524i\WP\APPENA.DOC Harding Lawson Associates 9 • Except as noted in Step 24 and in Section A2.9, groundwater samples will be transferred directiy from the pump discharge to the sample containers. VOC vials will be filled in a maimer that minimizes head space or air bubbles. Samples for VOC analyses will be collected first. VOC sample vials will be filled to capacity and tightly capped to avoid retention of an bubbles. Remaining sample containers will be filled to approximately 90 percent of capacity. VOC sample containers will be preserved and filled according to EPA Region II CERCLA Quality Assurance Manual protocol (p. 31) as follows: - Collect three 40-milliIiter vials of sample for VOC analysis. - Adjust the pH of one of the vials to less than 2 Standard Units by carefully adding 1:1 Hydrochloric acid (HCl) drop by drop to one of the filled 40-milliliter VOA vials. The number of drops of 1:1 HCl required will be recorded. The first vial may then be discarded. - Carefully add the same number of drops to the remaining two vials to be submitted for laboratory analysis. (The pH in the two vials for laboratory analysis should not be tested directly.) - Seal the vials. - The pH test is to be performed at each sampling location. - A fresh sample will be collected if an air bubble is detected in a VOC sample vial after sampling is complete. • Non-VOC samples will be placed into prepreserved laboratory-prepared sample bottles. A small portion of the sample will be poured over pH paper from the filled sample bottle into a second clean container. The pH of the sample material in the second container will be tested in the field to confirm that it falls within the requirements of the QAPP. Additional preservative and sample material will be used to adjust the pH of the sample, if necessary. • Field-filtered samples will be obtained for analysis of metals where required. A 0.45-micron filter of compatible inert material will be used in filtering the samples. The filtering device will be either an in-line filter or pressure filter apparatus. The filtering apparatus currently planned for use on this project is the Gelman Sciences AquaPrep^^ Flex Filter. The device uses a 10 mil PVC medical grade bag film with a Supor (inherently hydrophilic polysulfone) membrane. The groundwater samples for field filtration will be fransferred directly from the pump discharge line to the filter. • Preservation of samples to be analyzed for metals will be conducted after filtering. The filtered samples wiU be fransferred dfrectly from the filter apparatus to pre-preserved sample bottles. A small portion of the sample will then be poured out of the bottle for pH testing. If necessary, the pH of the sample vdll be adjusted by adding additional preservative. • Immediately after filling, samples will be placed in storage coolers on ice. Samples will be checked periodically with a thermometer to ensure preservation requirements are met. The temperature of the samples will also be recorded by the laboratory upon receipt. • Sample depth will be recorded, the groundwater sampling field data sheet will be completed and signed, and the chain-of-custody form will be signed. • The well cap will be closed and the well will be locked. Quality assurance/quality confrol (QA/QC) samples are discussed in the QAPP (Appendix C). to 2.7 Onsite VOC Analysis by Gas Chromatograph o to Groundwater samples will be handled and analyzed onsite using a portable GC as described below. oo ' o • Groundwater samples will be collected as described in steps 2 through 21 of Section 2.6. F:\3524i\WP\APPE.NA.DOC Harding Lawson Associates 10 • 20 mLs of groundwater will be collected in a 40-mL vial. • The sample will then be agitated (shaken) for 2 minutes. • A dedicated syringe will then be inserted into the vial and a measured volume of gas from the sample vial headspace will be collected for analysis using the GC. The GC utilized will be a PID equipped with an 10.6 elecfron volt lamp. The chromatographic column will be a 10-meter capillary column of fused silica coated with the adsorptive material. The inner diameter of the capillary column vdll be 0.021 inches (0.53 mm). Precolumn backflush will use a 9-meter analytical column and a 1-meter precolumn. Computing integrators will be used to plot the chromatogram for the detector analysis and to compute and record the area of the chromatographic peaks. The peak areas will be used to calculate concentrations for each of the compounds analyzed. The field QC procedures will be performed as set forth in the QAPP addendum (Appendix CD). As discussed during the May 12, 1997 meeting with EPA, the results ofthe proposed onsite analysis of TEX compounds in groundwater using a field gas chromatograph (GC) will be defined as "Screening Data with Definitive Confirmation". A detailed definition of "Screening Data with Definitive Confirmation" was supplied to the EPA in Section C2.0 of HLA's Draft Remedial Investigation Workplan (Workplan), dated August 5, 1994. Confirmatory samples will be collected at the rate (10%) described in this Workplan. The confirmatory samples will be analyzed using CLP methodologies by a certified laboratory. Field screening will be performed on the headspace of a water sample utilizing a GC equipped with a photoionization detector (PID). The field screening method is based upon the principle that when a water sample containing VOCs is sealed in a vial, VOCs will equilibrate between the water and vial headspace. The application of field screening methods for determination of VOCs in water has been reliably demonstrated as described by the following : Mackay, D., Shiu, W.Y., and Wolkoff, A.W., 1975: Gas Chromatographic Determination of Low Concenfration of Hydrocarbons in Water by Vapor Phase Extraction; in Water Quality Parameters, ASTM STP 573, American Society for Testing and Materials, p. 251-258. ; And McAuliffe, J., 1976: GC Determination of Solutes by Multiple Phase Equilibrium; Chemical Technology, v.l p. 46-51. This method of field screening has also been compared to purge and trap procedures with excellent correlation and exhibits a standard deviation of 5% for routine analysis of water as described by the foUowdng : Dietz, E.}., Jr. And Singley, K.F., 1979: Determination of Chlorinated Hydrocarbons in Water by Headspace Gas Chromatography; Analytical Chemistry, v.51 No. 11 p. 1809-1814. 2.8 Aquifer Slug Testing Aquifer slug tests will be performed at select wells during the implementation of the RIWPA. One rising head test will be performed at the wells in which the water table intersects the screened interval. In wells in which the water level is above the top of the screened interval, a falling head and a rising head test will be performed. The tests will be conducted using a data logger and pressure fransducers with chemically resistant cables. The data logger will be pre-programmed to collect incremental water o level measmements using an approximately logarithmic time scale. Field decontamination procedures ^^ will be conducted as described in Section A2.4.2.2. The following procedures will be used during the QQ slug tests: H 1. Before beginning each test, the foUowing information will be recorded: • Well internal diameter F:\3524i\WP\APPENA.DOC Harding Lawson Associates 11 to Location and elevation reference point from which water depth measurements are made Pre-test static water level (and elevation) of groundwater with respect to the reference point Date, time, and name(s) of personnel conducting test Well, depth, screen depth and length, well radius, and depth, length, and radius ofthe gravel pack Volume of dimensions of slug Type of test (falling or rising head) Test number as recorded by the data logger Type of measuring device used 2. An initial depth-to-water measurement will be collected and recorded. 3. A decontaminated pressure fransducer will be lowered into the well to a depth below the anticipated greatest depth of the slug. The water level will then be allowed to equilibrate. 4. The data logger will be initialized and set to the referenced water level 5. To initiate the falling head test, a decontaminated PVC or stainless steel slug will be completely infroduced into the well as rapidly as possible while the data logger is started simultaneously. The slug vnll be of sufficient volume to displace a quantity of water that will require the well at least five minutes to equilibrate. 6. The falling head test will continue until the water level has returned to 90 percent of static. 7. Once the water level has returned to static, the rising head test can begin. The rising head test will be conducted by completely removing the slug from the well as rapidly as possible while simultaneously starting the data logger simultaneously started. The rising head test will continue until the water level returns to at least 90 percent of static. 8. The data will be downloaded directly from the datalogger to a portable computer in the field. The data will be used for analysis (using AQTESOLV®) of hydraulic conductivities using the Bower and Rice method. 9. If the data cannot be downloaded directly to a computer, the data will be printed in the field. A field geologist or engineer wiU keep detailed notes for each test. to o to to 00 to F;\3524i\WF\APPENA.DOC Harding Lawson Associates 12 APPENDIX C QUALITY ASSURANCE PROJECT PLAN i 302283 APPENDIX CD CONTENTS CDI INTRODUCTION 1 CD2 ONSITE VOC ANALYSIS USING THE GC 2 CD3 LABORATORY ANALYTICAL PARAMETERS AND METHODS 5 CD3.1 Onsite GC Analysis 5 CD3.2 Certified Laboratory Procedures ^ 5 Ui o to to 00 G:\work\35241\qapp2.doc Harding Lawson Associates CDI INTRODUCTION This Addendum to the Quality Assurance Project Plan (QAPP, HLA 1994) has been prepared by Harding Lawson Associates (HLA) on behalf of Island Chemical Company, Inc. (ICC). This QAPP Addendum has been prepared as an Appendix to the EPA-approved Remedial Investigation Work Plan (RIWP). This Addendum to the QAPP will be included in the RIWP as Appendix CD. The RIWP Addendum (RIWPA) includes the following analytical activities which were not specified in the original EPA-approved RIWP, and therefore not included in the original QAPP: • Onsite analysis ta groimdwater using a gas chromatograph (GC) • Shelby tube soil sampling for analysis of grain size, percent moisture, total organic carbon (TOC), and porosity • Nufrient profile in soil including analysis of alkalinity, ammonia, iron, sulfate, sulfide, nifrate, nifrite, pH, and ortho phosphorus. Other procedures and quality assurance and quality confrol (QA/QC) protocol for activities plarmed during the implementation of the RIWP Addendum are discussed in the RIWP- Quality Assurance and Procedures Plan (QAPP, Appendix C). to o to to 00 tn G:\work\35241\qapp2.doc Harding Lawson Associates CD2 ONSITE VOC ANALYSIS USING THE GC Sample documentation v»dll be consistent with that described the QAPP (Section 3.0), with the exception of a chain-of-custody form. The samples collected for onsite analysis will be logged in the field book, and analyzed immediately after collection. The following information will be recorded in the field book for each sample: Sample identification number Date and time of sample collection Sample location and depth Sampling techniques Sample type (media sampled) Container type Onsite calibration and maintenance records of the onsite GC will be maintained by the field GC operator. These records will be filed onsite and may be subject to a QA audit. The onsite GC operator will maintain spare parts for equipment and will be capable of making minor repairs as needed. Calibration records will be maintained as follows: 1. The GC operator will maintain a calibration record that will be kept with the GC at all times. 2. A label will be affixed to the GC showing description, manufacturer, model numbers, date of last calibration, calibrator's signature and due date of next calibration (where applicable). Reports and compensation or correction figures will be maintained with the insfrument. 3. Written step-wise calibration procedures will be available for each measurement instrument. The calibration procedures for the field GC are described below (Source: Vironex Field Analytical Services): 1. GC operator will perform a two-point calibration using a 5 microgram per liter (^g/L) 50ng/L and a 500 |ig/L standard of target compounds (toluene, ethylbenzene, and xylenes [TEX]). The 5 ug/L standard is prepared by filling a 40 milliliter (mL) vial vnth 20 mLs of deionized water and adding .5 microliters (^L) of a 200 i^g/mL standard solution of VOCs in methanol. The 50 (ig/L standard is prepared by filling a 40 mL vial with 20 mLs of deionized water and adding 5 |aL of a 200 (ig/mL standard solution of VOCs in methanol. The 500 ug/L standard is prepared by filling a 40 mL vial with 20 mLs of deionized water and adding 50 nL of a 200 (ig/mL standard solution of VOCs in methanol. The detection limits (e.g. 5|ig/L) will be verified prior to sample analysis and at the start of each day 2. Agitate (shake) standards for 2 minutes prior to analysis. to o to 3. Calculate the response factor (RF) for each target compound for each calibration concenfration prior to analyzing site samples. to 00 G:\work\35241\qapp2.doc Harding Lawson Associates 4. Determine the average RF for each target compound. The RF for each compound must be within 80-120 percent of the average RF from the initial calibration. 5. Determine percent relative standard deviation (%RSD) for each target compound (the RSD may not exceed 20 percent). The GC analysis QA/QC techniques and frequencies are summarized below: • Analyze a insfrument blank (as described in Section C6.3.2) at the start and end of each day. • Analyze a method blank (as described in Section C6.3.2) at the beginning of each day and after any sample containing one or more target compounds. • Analyze one standard after every 10 samples. • Analyze one duplicate sample for every 20 samples. • Calibrate the insfrument 1) at the start of each day, or 2) when the GC operating conditions have changed, or 3) when the GC column type is changed, or 4) when the RF of the daily mid-point calibration check is not within 85 percent to 115 percent of the average RF from the initial calibration. • Analyze a mafrix spike sample and matrix spike duplicate samples at a rate of one per 20 samples. Groundwater samples will be analyzed onsite with a modified EPA Method 602 for toluene, xylenes, and ethylbenzene. A portable GC/PID (Photovac llS-f) equipped with a 11.7 elecfron volt lamp will be utilized for analysis. The groundwater samples will be handled and analyzed as described below. 1. Groundwater samples will be collected as described in steps 2 through 21 of Section AD2.6. 2. 40 mis of groundwater will be collected in a 40-ml vial and the cap with a Teflon septum will be sealed with no headspace. The sample will then be submitted to the onsite GC operator. 3. The operator will then fransfer a 20-ml aliquot of sample to a second, clean 40 ml VOA vial and the cap will be sealed. 4. The 20-ml sample will then be agitated for 2 minutes in the vial. This process efficientiy transfers the aromatics from the aqueous phase to the vapor phase (McAuliffe, 1976). 5. A dedicated gas-tight syringe will then be inserted into the vial and a measured volume of gas will be collected from the sample vial headspace. 6. The measured volume of gas will be injected into the gas chromatograph column, which will have been preheated to a temperature of 40° Celsius. The chromatographic column will be a 10-meter capillary column of fused silica coated with the adsorptive material. The inner diameter of the capillary column will be 0.021 inches (0.53 mm). 7. The gaseous sample will be fransported through the capillary column by laboratory t*) grade 99.99 % hydrocarbon free purified air. The GC is temperature programmed to i ^ separate the purgeables to be detected by the PID. The sample will then pass the PID jo where it wUl be ionized by the 11.7 eV lamp. Computing integrators will be used to plot oo -J G:\work\35241\qapp2.doc Harding Lawson Associates the chromatogram for the detector analysis and to compute and record the area of the chromatographic peaks. The peak areas will be used to calculate concenfrations for each of the compounds analyzed. Precolumn backflush will use a 9-meter analjrtical column and a 1-meter precolumn. The field QC procedures vrill be performed as set forth in the QAPP addendum (Appendix CD). to o to to 00 00 G:\work\35241\qapp2.doc Harding Lawson Associates CD3 LABORATORY ANALYTICAL PARAMETERS AND METHODS Several groundwater samples will be submitted for onsite GC VOC analysis. A certified laboratory will perform several analyses on soil samples. Analytical parameters and methods for the onsite GC analysis are described in Section CD3.1. Analj^cal parameters and methods for the certified laboratory analyses are identified in Section CD3.2. CD3.1 Onsite GC Analysis The onsite analysis using the GC will be conducted in accordance with EPA Methods 601 and 602 Modified. The method detection limits (MDLs) for the target compounds are as follows: Toluene Ethylbenzene Xylenes Methylene chloride Chloroform 5 ug/L 5 tig/L 5 ug/L 5 ug/L 5 ^g/L The GC that will be used to perform tiie onsite analyses can estimate concenfrations lower than those listed above. If detected concenfrations are below the given MDL, the result will be qualified to indicate that the concenti-ation is estimated. CD3.2 Certified Laboratory Procedures Laboratory analytical parameters, methods, and method reporting limits to be used during the implementation of the RIWPA, which were not specified in Section C5.4, are as follows: SOIL ANALYSIS Nifrate Nifrite Sulfate Sulfide Iron (total) Alkalinity Ammonia Ortho Phosphorus Total Organic Carbon pH Grain Size Analysis Porosity HCU bacteria count Total plate bacteria count Percent moisture METHOD EPA Method 353.2 EPA Metiiod 353.2 SW-846 9036 SW-846 9030 EPA Method 6010 EPA Method 310.1 EPA Method 350.2 EPA Metiiod 365.1 SW-846 9060 SW-846 9045 C Modified (M) ASTM D-422 By ASTM D-2216 and D-854 Standard Methods 9215C M Standard Methods 9215C M EPA 160.3 Modified REPORTING LIMIT 0.5 mg/kg 0.5 mg/kg 100 mg/kg 0.2 mg/kg 10 mg/kg 10 mg/kg 2.5 mg/kg 0.5 mg/kg 100 mg/kg Not Applicable Not Applicable Not Applicable Not Applicable Not Applicable Not Applicable NOTES: mg/kg = milligrams per kUogram. The listed reporting limits are subject to a slight change based on moisture content tAJ O to to 00 VD G :\work\35 24 l\qapp2 .doc Harding Lawson Associates DRAFT DISTRIBUTION Draft Remedial Investigation Work Plan Addendum-Phase III Virgin Island Chemical Site St. Croix, U.S. Virgin Islands June 20, 1997 Copy No. Copies 1 - 7: Copy: 8 (unbound): Copy 9: Copies 10-11: Copy 12 -13: Ms. Caroline Kwan United States Environmental Protection Agency Region II Emergency and Remedial Response Division 20th Floor 290 Broadway New York, New York 10007-1866 Ms. Carol Burns, Esq. Office of Regional Counsel United States Environmental Protection Agency 290 Broadway New York, New York 10007-1866 Mr. Cecil Williams Mr. Syed Syedali Department of Planning and Natural Resources Division of Environmental Protection Bldg. I l l - Apt. 14A Water Gut Homes -1118 Christiansted, St. Croix U.S. Virgin Island 00820 5065 Ms. Pamela J. Philips CDM Federal Programs Corporation Suite 710 111 Fulton Sfreet New York, New York 10038 Copies 14 - 15: Sills, Cummis, Zuckerman, Radin, Tischman, Epstein & Gross One Riverfront Plaza Newark, New Jersey 07102-5400 302290 DRAFT DISTRIBUTION (continued) Copies 16 - 19: Harding Lawson Associates Princeton Junction, New Jersey QuaUnr Assurance/Quality Confrol Reviewer Jason M. Schindler, P.G. Associate Hydrogeologist This document was preparedfor the sole use ofthe ICC and the regulatoty agencies involved with the project, the only intended beneficiaries of our work. No other parties should rely on the information contained herein without the prior written consent of HLA. JSV/jmc/ F:\35241\WP\R001.DOC 302291