Remedial Investigation Work Plan

Remedial Investigation

Work Plan Citizens Gas Works

Former Manufactured Gas Plant Site

GEI Consultants, Inc. 188 Norwich Avenue P.O. Box 297 Colchester, Connecticut 06415 (860) 537-0751 S U B M I T T E D T O

KeySpan Energy Corporation One MetroTech Center Brooklyn, NY 11201-3850 David B. Terry Program Manager February 11, 2003 982482-1901

KeySpan Energy Corporation Remedial Investigation Work Plan February 11, 2003

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Table of Contents

1. Introduction 1

2. Site Background 3 2.1 Site Description and History 3 2.2 Local Environment 5 2.3 Areas of Potential Environmental Concern/Conceptual Site Model 5

2.3.1 Parcel I: Vacant Lot Owned by NYC 7 2.3.2 Parcel II: Owned by NYC, Leased to Ferrara Brothers 8 2.3.3 Parcel III: Electronics Warehouse 8 2.3.4 Parcel IV: Holder No. 5 9

3. Scope of Work 10 3.1 Supplemental Document Review and Preliminary Site Visit 10 3.2 Field Investigation Preparation and Mobilization Activities 11

3.2.1 Site Security 12 3.2.2 Establish Decontamination Area and Waste Storage Area 12 3.2.3 Establish a Waste Storage Area 13 3.2.4 Identify Sample Locations and Underground Utilities 13

3.3 Field Investigation Sampling and Analysis 13 3.3.1 Surface Soil Sampling 14 3.3.2 Test Pits 14 3.3.3 Soil Borings and Monitoring Wells 15 3.3.4 Air Monitoring 18 3.3.5 Well Development 18 3.3.6 Waste Disposal Sampling 19 3.3.7 Groundwater Sampling, Storm Sewer Evaluation, Hydraulic

Conductivity 19 3.3.8 Hydraulic Conductivity Testing 20

3.4 Step I Fish and Wildlife Impact Analysis 20 3.5 Qualitative Human Health Risk Assessment 21 3.6 Survey and Sample Point Location 21 3.7 Quality Assurance/Quality Control and Data Validation 21

4. RI Report Preparation 23 4.1 Data Reduction and Data Summary 23 4.2 RI Report 23


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5. Schedule 25

6. Project Team 26

Table

1. Sample Descriptions, Rationale and Proposed Analysis

Figure

1. Site Location Plate

1. Proposed Sample Locations

Appendices

A. Previous Site Data B. Severn Trent Laboratories – Connecticut, Quality Assurance Project Plan C. Community Air Monitoring Program D. GEI Standard Operating Procedures

J:\WPROC\Dbt\KEYSPAN\Citizen's Gas\RI Work Plan\Citizens RI WorkPlan 013103.doc


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1. Introduction On behalf of our client, KeySpan Energy Corporation (KeySpan), GEI Consultants, Inc. (GEI) has prepared this Remedial Investigation (RI) Work Plan for the Citizens Gas Works former Manufactured Gas Plant (MGP) site (Site) located in Carroll Gardens neighborhood of Brooklyn, Kings County, New York. The work plan is submitted to the New York State Department of Environmental Conservation (NYSDEC) and the New York State Department of Health (NYSDOH) for their review and approval as part of KeySpan’s Voluntary Cleanup Application for the Site. Implementation of the scope of work described in the Work Plan is intended to generate sufficient data to complete the RI, thereby defining the nature and extent of soil and/or groundwater impacts associated with the former MGP operations. GEI developed the scope of work with input from Dvirka & Bartilucci Consulting Engineers (D&B), the City of New York (NYC) and its consultant, Lawler Matusky & Skelly Engineers. In addition, the following documents were used to develop this work plan. § Vacant Property Site Assessment, Carroll Gardens, Brooklyn, TRC Environmental

Consultants, October, 1985 § Phase I Site Assessment, EA Science and Technology, 1985

§ Environmental and Engineering Study Assessing the Suitability of the Gowanus Canal

Site for Public Housing and Recreational Use, Stone & Webster Engineering Corp., 1984 § Engineering Investigation at Hazardous Waste Sites, Phase II Investigations, Carroll

Gardens, Site 224012, Roux Associates, Inc. September 1990 § Brooklyn Union Preliminary Plan for the Carroll Gardens Site Investigation, June 14,

1995 § Citizens Works Former MGP Site, Carroll Gardens, NY, Technical Scope of Work-Site

Investigations, Dvirka & Bartilucci, March 7, 2000 § Comments on the March, 2000 D&B Scope of Work, City of New York and Lawler

Matusky & Skelly Engineers, undated The Work Plan has been prepared to be consistent with the NYSDEC draft Guidance for Site Characterization and Remedial Investigations. In addition, this work plan incorporates comments provided by NYSDEC regarding a September 4, 2003 draft prepared by GEI and


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several meetings at the site and discussions between KeySpan, GEI, and representatives from the City of New York, NYSDEC, and NYSDOH. The purpose of this work plan is to describe the methods and procedures to be implemented in performing the RI. This Work Plan includes the following components: § A brief summary of the site history § A discussion of the site location and environmental setting § A discussion of the potential areas of environmental concern (potential AOECs) § A conceptual site model § A sampling and analysis plan

The appendices contain a quality assurance project plan (QAPP), GEI standard operating procedures (SOPs) and a site-specific health and safety plan (HASP).


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2. Site Background 2.1 Site Description and History The former MGP was owned and operated by Brooklyn Union Gas (BUG) [a predecessor company of KeySpan Energy] prior to being decommissioned and demolished in the early 1960s. The Site consists of four parcels, two of which are currently owned by the City of New York and two owned by private parties. The Citizens Works former MGP site comprises approximately 12 acres in Carroll Gardens, Kings County (Borough of Brooklyn) New York (see Figure 1). The City-owned parcels, Parcels II, and I total 5.8 acres and are known as the “Public Place.” The site is located approximately 1,500 feet northeast of the intersection of the Gowanus Canal and the Gowanus Expressway in the Borough of Brooklyn. The four parcels constituting the site (described below) are bounded on the south/southeast by the Gowanus Canal, on the west by Smith Street, on the southwest by Huntington Street, and on the north/northeast by Fifth Street with the exception of Parcel IV, which is north of Fifth Street. A mix of residential, industrial, and commercial development surrounds the site. The site is relatively flat and slopes gently to the southeast toward the Gowanus Canal at about a 4 percent grade. The site is approximately 10 to 30 feet above mean sea level. A historical site plan presented on Plate 1 shows the location of known structures that existed at the site. A description of the current and past uses of the former MGP site follows: § Parcel I (Tax Block 471, Lot 1). This 3.6-acre parcel is currently a vacant lot on the

northwestern portion of the site that is owned by the City of New York (NYC) and has been subject to unauthorized dumping since the 1970s. The majority of dumped material appears to be construction-related debris with mixed in auto bodies and other materials including several unidentified drums. This portion of the site formerly housed the majority of the structures associated with the coal and oil gasification process. Former structures associated with this parcel include four gas holders, condensers, generator house, boiler house, exhauster house, purifier houses, oil tanks, scrubbers, seal pots, purification towers, and pump tanks.

§ Parcel II (Tax Block 471, Lot 100). This 2.2-acre parcel is in the northeastern portion

of the site. This parcel is currently owned by NYC and is leased to Ferrara Brothers who operates a concrete plant. This portion of the site formerly housed coal hoppers, coal trestles, a condenser, engine room, settling tank, oil room, and storage areas.


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§ Parcel III (Tax Block 471, Lot 200). This approximately 4.5-acre parcel is in the southwestern portion of the site. This parcel was sold to Mr. Irving Goldstein in 1970, who developed the site as a warehouse for 47th Street Photo. The 47th Street Photo is no longer in business and the current occupant of the warehouse (if any) is unknown. This portion of the site formerly housed oil tanks, separators, tar settling tanks, tar storage tanks and a coal storage area.

§ Parcel IV (Tax Block 468, Lot 25). This approximately 1.04-acre parcel is privately

owned and is currently a parking lot. According to the New York City on-line tax records, the parcel is owned by Alfonso Figliolia. This parcel is located between Fourth Street on the north, Fifth Street on the south, and Hoyt Street on the east. The parcel is abutted by commercial/industrial and residential parcels on the west side. A gas holder (Holder No. 5) was formerly located on this parcel.

The Site was initially constructed in the 1860s as a coal gasification plant and was converted to an oil gasification plant in 1952 until its closure in the early 1960s. Initially, the former MGP site was located primarily on the northern and southeastern portions of the site. Based on a review of construction/site plans, the initial MGP consisted of three gas holders, a retort house, and coal storage areas. A fourth gas holder is also depicted in the northeastern portion of the site on Sanborn Maps. The southwestern portion of the site was subsequently developed in the early 1900s. A fifth gas holder was constructed on the northern corner of Fifth Street and Hoyt Street sometime between 1904 and 1939. The former MGP site was decommissioned and demolished in the early 1960s. In 1970, Parcel III was sold to Mr. Goldstein, who built the existing warehouse on the southwestern portion of the site. In 1975, Parcel II was leased by the City to the Ferrara Brothers, who had been operating and continue to operate a concrete plant on this northeastern portion of the site. A comprehensive history of ownership for each of the parcels was not available for the preparation of this work plan. The scope of work will include additional research regarding the chain of ownership and development history that will be presented in the final RI report. On behalf of the City, Stone and Webster Engineering Corp. conducted an environmental investigation of the Public Place portion of the site in 1984. Stone and Webster Engineering Corp. completed a report titled “Environmental and Engineering Study Assessing the Environmental Suitability of the Gowanus Canal Site for Public and Recreational Usages.” In 1985, TRC Environmental Consultants Inc. conducted shallow subsurface soil sampling that revealed volatile organic compounds (VOC) and semivolatile organic compounds (SVOC) present in site soils. In 1989, Roux Associates conducted a Phase II investigation that revealed benzene, toluene ethyl-benzene and xylene (BTEX), poly aromatic hydrocarbons (PAHs) and metal contamination in shallow subsurface soil and groundwater.


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The City is considering potential future uses of Parcels I and II. Its current designation as a ‘Public Place’ under the jurisdiction of the City’s Department of Parks and Recreation would preclude another use of the property in absence of a new discretionary action by the City. 2.2 Local Environment The surficial geology of the site is characterized by unconsolidated Holocene (recent) deposits of beach/shore, salt-water marsh and/or alluvium. These deposits are underlain by glacial till and outwash deposits. The surficial geology underlying the site is described as Quaternary till deposits of variable texture. The till was generally deposited beneath glacial ice and consists of variable textured material (clay, silt-clay, boulder clay) (Surficial Geologic Map of New York, Lower Hudson Sheet (1989), The State Education Department, University of the State of New York, Compiled by Donald H. Cadwell). The Gardiners Clay underlies the glacial deposits. The Jameco Gravel underlies the Gardiners Clay. Drinking water is supplied by the NYC aqueduct system (which receives water from upper state New York) and is the sole source of drinking water within a 3-mile radius of the site. Pre-Cambrian metamorphic bedrock underlies the unconsolidated deposits at the site. Borings drilled as part of past construction or site investigation provide a general understanding of the site-specific lithology. The site is underlain by approximately 15 feet of fill consisting in part of cinders and coal. Below the fill are soils described as “boggy” and are approximately 10 feet thick. It is not known if these boggy soils are consistent across the site. The boggy soils are underlain by clayey till deposits that range in thickness from 118 to 150 feet. Under this significant till layer are the more permeable Jameco gravel formation. The Jameco Gravel overlies bedrock. The water table across the site ranges from 10 to 20 feet below ground surface (bgs). Groundwater generally flows south/southeast toward the Gowanus Canal. 2.3 Areas of Potential Environmental Concern/Conceptual Site

Model Although helpful, the past data are not sufficient to make definitive conclusions relative to the degree and extent of the contamination. In addition, activities such as filling, unauthorized dumping and site maintenance have the potential to alter soil and/or groundwater quality since the last collection of data in 1989. However, the previous investigations were used to develop the site conceptual model and direct the proposed sampling efforts. Data from previous


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investigations are presented in Appendix A. The RI report will incorporate previous data and an evaluation of the relevance of those data to the current understanding of the site. The objective of the RI includes the identification of potential source areas, a determination of the nature and extent of any identified contamination, the identification of potential pathways of contaminant migration and possible receptors, and an evaluation of the need for corrective measures, if any. In addition, a qualitative human health risk assessment will be performed in accordance with the NYSDOH’s November 9, 2000 Qualitative Human Health Exposure Assessment (Appendix 1B to NYSDEC’s Draft Site Characterization and Remedial Investigation Guidance document). Prior to the discussion of the proposed scope of work, it is helpful to review what is known or can be deduced from existing data about the sources, nature and anticipated distribution of possible contamination on the site. The site was used from the mid 1800s to the mid 1960s for the manufacturing of gas. The majority of the operation, up until the 1950s, utilized coal as the feedstock for gas production. In the 1950s the process changed over to heavy oil as a feedstock. Since the closure of the MGP the property has been subdivided and utilized for various purposes as generally described in the previous section of this work plan. The accumulation of solid waste and debris on the property has in past investigations been reported to contain drums, cars and other materials that could possibly contain hazardous substances. The on-site activities or features of potential environmental interest therefore relate primarily to the former MGP and the dumping on Parcel I. Shallow soil samples previously collected indicate the presence of MGP-related VOCs and SVOCs. Groundwater at the site also contains MGP-related SVOCs, VOCs, and cyanide in and around the more densely developed areas of the former MGP. The existing, limited data suggest greater groundwater impacts downgradient from the former MGP adjacent to the Gowanus Canal than at other locations on the Site. Pesticides were detected in some shallow soil samples collected in 1989. Pesticides are not associated with former MGP operations and are most likely the result of the unauthorized dumping. The last available data for the site were collected in 1989. Since that time additional unauthorized dumping has occurred at Parcel I. In addition, other changes to surface conditions are probable throughout all four parcels from normal activities associated with operations, maintenance, and property improvements. Accordingly, past shallow soils data is of limited value to characterize current conditions at the site.


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The individual features associated with the former MGP that could have caused a release to soil or groundwaters are many and are located in various portions of the site. At this stage of investigation we propose identifying the potential AOECs as the four individual parcels as opposed to focusing on each individual former MGP structure that may have contributed to site impacts. Features within each parcel will be evaluated relative to the potential to be a source area and/or act as a migration pathway. This organization of the site and data collected could facilitate future remediation and development decisions that may only consider one parcel at a time. A discussion of the potential AOECs, their potential contaminant source areas, migration pathways, and environmental receptors, follows. 2.3.1 Parcel I: Vacant Lot Owned by NYC Parcel I had the highest density of former MGP structures and has been the subject of many years of unauthorized dumping. Water table groundwater from Parcel I would eventually flow toward the Gowanus Canal. The unauthorized dumping activities would likely impact the soils from direct spillage from any liquids in the dumped material and leaching from the solid materials. Groundwater impacts from such releases of dumped materials may also be present. Aerial photography indicates that some of the former MGP sub-grade structures (e.g., circular gas holders) exist on the site. Any abandoned footings and foundation walls could act as barriers to contaminant migration depending on the depth and orientation. It is also possible that sub-grade former MGP structures could contain residual tar from the former process. Parcel I also contained two former MGP purifier houses. Purifier materials commonly consisted of iron treated wood chips that filtered impurities from the gas. Once the purifier material could no longer be re-vivified, it was typically land disposed. A grouping of oil tanks existed at the southwestern corner of Parcel I. Any releases from the tanks would be expected to be evident from residual oil in soil or groundwater under the former tank location. The former generator and boiler houses likely did not have large quantities of on-site fuel and/or tar storage. Accordingly, these structures would have a relatively lower probability of being a source area. However piping to these structures may have caused historic releases. Other former MGP structures exist on Parcel I that are of potential environmental concern. These structures include the condensers east of Holder #3, the pump tanks, the seal pots, and scrubbers.


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A 6-foot-diameter former sewer is shown crossing the southeastern (downgradient) corner of Parcel I. This sewer is perpendicular to the direction of groundwater flow and has the potential to affect contaminant migration. If the sewer invert intercepts the water table, preferential flow toward the southwest and to a lesser extent, the northeast may occur. 2.3.2 Parcel II: Owned by NYC, Leased to Ferrara Brothers This parcel is currently being used as a concrete batching and distribution plant. The former MGP had some former structures of environmental concern that include the following.

§ Engine room § Condenser § Settling tank § Oil room (northernmost area against bulkhead) § Pump house

In addition, the storm drainage system and the former sewer line are potential conduits for preferential migration of contaminants. Groundwater flow across the parcel is southeast. 2.3.3 Parcel III: Electronics Warehouse According to the on-line tax records, this parcel is owned by Vichar, Inc. and has recently been used for the warehousing of electronic and camera equipment. A portion of the site is developed with the warehouse that limits access for the investigation. However, the former MGP structures and other features of environmental concern are concentrated along the eastern side and are not under the developed portion of the parcel. Former MGP structures of potential environmental concern are located in the northeast corner of the parcel and include the following:

§ Separator § Tar settling tanks § Pump houses (2) § Tar tank § Tar storage tanks (2) § Oil tank No. 12 § Other unidentified tanks (visible on aerial photographs)

Other structures on the parcel could act as conduits for contaminant migration. The former sewer line trends across the entire site. Parcel III is downgradient from the some of the significant MGP structure located on Parcel I and may be impacted from any releases there.


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2.3.4 Parcel IV: Holder No. 5 This parcel is currently a parking lot and is owned by Alfonso Figliolia. The parcel once held the largest of the gas holders of the former MGP. Groundwater flow from the site is likely southerly across Fifth and Hoyt Streets toward Parcels I and II.


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3. Scope of Work The scope of work presented in this work plan addresses field investigation tasks that will provide a better understanding of the extent and degree of soil and groundwater impacts on the four parcels. The type of environmental sampling and the number and depth of sampling locations have been developed based on a review of a preliminary site inspection and a preliminary review of historic sources of information such as Sanborn Maps, as well as other historic site engineering drawings and environmental assessments provided by KeySpan. In addition, a suggested scope of work provided by NYSDEC has been taken into consideration. Accordingly, the proposed sampling program includes sampling of groundwater, surface soil, and subsurface soil. The scope of work addressed by this work plan includes the following tasks. § Preliminary Site Visit § Survey location of key former MGP structures § Soil Borings, Test Pits, Monitoring Well Installations, Surface-Soil Sampling § Air Monitoring § Groundwater Sampling, Storm Sewer Assessment, Hydraulic Conductivity Testing, and

Water Level Measurement § Step I Fish and Wildlife Impact Analysis (FWIA) § Qualitative Human Health Risk Assessment § Data Reduction and Data Summary § RI Report Preparation § Presentation of Findings

Descriptions of each proposed work activity are provided separately below. 3.1 Supplemental Document Review and Preliminary Site Visit The initial element of the investigation will involve collecting and reviewing background information to supplement the existing historical information utilized to prepare this initial scope of work. This background information will further focus the field investigation, particularly with respect to determining potential source areas. The following is a list of sources of information and investigation techniques that may be utilized in order to better understand the site history and to identify potential areas of environmental concern:


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§ Prior environmental studies/reports § Local agency files § State and federal environmental databases § Interviews with past/present property owners/operators § Interviews with representatives of KSE § Historic aerial photographs § Site plans and construction drawings § Historic Sanborn (fire insurance) Maps § Historic Brooklyn Union Gas information available from KSE files

Based upon the results of the document review, GEI will attempt to field locate significant MGP structures to the extent practicable. A number of former MGP structure foundations and footers are visible and identifiable at the ground surface. GEI proposes to survey the locations of these features and to use the existing construction plans of the former MGP to survey locate a number of key structures. These structures will be staked out in the field and test pits (see subsection 3.3.3) will be used to confirm the location, configuration, and contents of foundations/footings of structures that may represent source areas. The initial surveying of the structure locations will help ensure that proposed borings, wells, and test pits are appropriately located to evaluate specific potential areas of concern. In addition to the structures, the approximate locations of the proposed sampling locations shall be identified in the field. One significant logistical issue for the sampling effort will be the timing of the removal of the debris from Parcel I by the City. Prior to the commencement of the investigation, non-MGP-related debris shall be identified, characterized, and removed by the City. The City will prepare a sketch showing the identified areas. Any stockpiles of soil left on the site after removal of debris shall be tested as part of the RI scope of work. 3.2 Field Investigation Preparation and Mobilization Activities Upon approval of the Work Plan by the NYSDEC and authorization from KeySpan, GEI will mobilize to the site and prepare for the field investigation program. A field operations center will be set up on the site in a mobile van or a construction trailer. The initial field mobilization will include the following items to be completed at the commencement of the field RI activities: § Establish a field operations center § Establish a decontamination area § Establish a waste storage area § Identify proposed sample locations § Identify underground utilities


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3.2.1 Site Security KeySpan and its contractors have been granted access to City-owned parcels pursuant to the “Access Agreement Between the City of New York and Brooklyn Union Gas d/b/a KeySpan energy Delivery – New York,” dated July 2002 (access agreement). The gates to any existing site fencing shall be equipped with two “buddy locks,” one owned by the City, the other owned by KeySpan. A temporary fenced “corral” may be constructed to provide security for the site trailer, field equipment and the night storage of contactor’s heavy machinery. 3.2.2 Establish Decontamination Area and Waste Storage Area Equipment decontamination will take place on a plastic lined, bermed decontamination area. During the preliminary site visit, the location of the decontamination area will be chosen. Potable water is not believed to be available to certain portions of the site; consequently potable water for decontamination will need to be staged at the site in close vicinity to the decontamination area. Drilling equipment (e.g., drill rods and auger flights) from the hollow stem auger drill rig and the bucket from the backhoe equipment will need to be steam cleaned with a pressure washer within the established decontamination area. Wastewaters produced during the steam cleaning will be collected from the decontamination pad and placed into USDOT/UN-approved drums, labeled and stored at the established waste storage area at the site. The drums will be characterized and properly disposed of by KeySpan. Sampling equipment used for sample collection (e.g., stainless steel split spoons, sample spoons, and hand trowels) will be decontaminated prior to use and reuse, or disposable sampling equipment will be used. Sampling equipment will be conducted according to SOP No. SA-007 (Appendix D), as outlined below: § Non-phosphate detergent and tap water wash § Tap water rinse § 10% nitric acid solution rinse § Distilled water rinse § Methanol rinse § Distilled water rinse

All decontamination liquids will be collected and stored within 55-gallon USDOT/UN-approved drums at the established waste storage area and will be subsequently characterized and disposed of by KeySpan.


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3.2.3 Establish a Waste Storage Area Investigative derived wastes including soil cuttings, groundwater, and decontamination waters will be collected and stored within 55-gallon USDOT/UN drums at the established waste storage area. The drums will be placed on a plastic lined, bermed waste storage area. The location of the waste storage area will be decided during the preliminary site visit to be completed prior to the start of the field investigation. 3.2.4 Identify Sample Locations and Underground Utilities During the preliminary site visit, the approximate sample locations will be determined and marked by GEI personnel. The proposed locations will be measured from existing structures. Each sampling location will be marked with stakes and/or white paint. Once marked, the drilling subcontractor will provide the boring locations to the one call utility clearance to identify potential utility conflicts at the site. In addition, information regarding potential utility conflicts on the private parcels will attempt to be obtained by KeySpan prior to commencement. KeySpan will obtain the necessary permits and written access agreements to complete RI activities on privately owned parcels (Parcel III and IV) and Parcels I and II owned by the City of New York. In addition, GEI will coordinate with the City for the removal of non-MGP debris according to the terms and conditions of the Access Agreement. The tenants of Parcel II, which is currently an active concrete processing plant, will be notified of the proposed duration and schedule of activities. 3.3 Field Investigation Sampling and Analysis This section of the RI Work Plan discusses the proposed surface soil samples, test pit, soil boring, and groundwater monitoring well installation activities. Table 1 presents the general rationale and proposed sampling and analysis for the surface samples, test pits, borings, and groundwater monitoring wells. The proposed sample locations are shown on Plate 1. The sample description, rational and analysis are shown in Table 1. In addition, air monitoring, well development, groundwater sampling, and hydraulic conductivity testing procedures to be implemented are discussed. The proposed analyses, analytical methods, and QA/QC samples are discussed under each of the following subsections for surface soil, test pit, soil boring, and monitoring well sampling procedures. Appendix D includes GEI’s standard operating procedures (SOPs) that will be implemented during the collection of samples for analysis. Subsection 3.7 discusses laboratory data deliverables and data validation procedures. Severn Trent Laboratories (STL) of Shelton, Connecticut will perform the analyses. STL is a New York State ELAP approved laboratory. STL’s QAPP is provided as Appendix A.


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3.3.1 Surface Soil Sampling Surface-soil samples (21 total) will be collected from the four parcels in areas where there have been no disturbances caused by other field activities. An exception will be Parcel I where surface soil sampling will be conducted after the City removes the non-MGP debris. Collection of soil samples from any soil stockpiles formed, as part of the City’s removal activity is included in this program. It is assumed that four stockpile samples will be required. Stainless-steel sampling implements (including spoons or trowels) and stainless steel bowls will be used to collect each surface soil sample from the 1-square-meter area from the upper two inches beneath any turf or vegetative layer. The exposed soil will be screened for volatile organic compounds (VOCs) using a photoionization detector organic vapor analyzer (PID-OVM). A discrete VOC soil sample will be collected from the area of the highest PID-OVM reading. No compositing or mixing of the sample will occur. Each surface soil sample will be sampled for a VOCs by the Environmental Protection Agency (EPA) Method 8260; semivolatile organic compounds (SVOCs) EPA Method 8270; the eight Resource Conservation Recovery Act (RCRA-8) metals; total cyanide (TCN); polychlorinated biphenyls (PCBs); and EPA Method 8081 pesticides. Each sampling implement will be decontaminated in accordance with decontamination procedures described in GEI’s SOP’s (Appendix D). Quality Assurance/Quality Control (QA/QC) samples will include blind duplicate surface soil samples, matrix spike/matrix spike duplicate (MS/MSD) samples, and equipment rinsate blank samples. The quality control samples will be completed at on a frequency of 1/20 or once per week of sampling. Severn Trent Laboratories (STL), an approved New York State ELAP laboratory will perform the analyses. One trip blank will be included per shipment of samples to the laboratory. Sample locations are shown on Plate 1. Sample descriptions, rational and analysis are shown in Table 1. 3.3.2 Test Pits Test pits (at least 19 total) are proposed to be excavated at the former Citizens Gas Works MGP site. The proposed test pit locations are shown on Plate 1, and the descriptions, rationale, and analysis are presented in Table 1. Backhoe test pits will be used to assess the configuration and contents of former MGP structures and to investigate shallow subsurface soil conditions at the site. In some larger structures test pits may be dug as trenches, or additional test pits may be excavated to assess the extent, configuration, and visual contents. Decisions to conduct additional test pits will be made in the field and be dependent upon actual conditions encountered. For example, a single test pit combined with the surface manifestation of the foundation may be enough to assess the size, construction, and contents of a former gas holder.


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Alternatively, several test pits or a trench may be required to better assess the extent and configuration of buried structures. Each test pit will be photographed and logged by a GEI scientist or engineer personnel during the excavation. Each test pit excavation will be completed in accordance with GEI SOP SS-006 (Appendix D). Test pits will be completed with a rubber-tired backhoe and will have the nominal width of 3 feet and will be terminated at practical extent of the equipment which is approximately 15 feet or the groundwater table which is anticipated to be located approximately 10 to 20 feet bgs. Excavated soils from the test pit will be placed onto plastic sheeting. Field screening of soils will be conducted with a PID-OVA for the presence of VOCs from the ground surface to the entire depth of the excavation. Based upon the observations and the field screening one soil sample will be selected per 31 estimated test pits. Samples will be selected from the area exhibiting the most prominent signs of contamination. Each sample will be analyzed for VOC, SVOC, RCRA–8 metals, total cyanide, PCBs, and pesticides. The location of the test pits is shown in Plate 1. After the completion of the test pit, the test pit will be backfilled in reverse sequence in which it was excavated, so that materials removed from the bottom of the test pits are placed back at the bottom and materials removed from the top of the test pit are placed back at the top. If test pits are excavated in paved areas, the pavement will be restored following completion. Each sampling implement will be decontaminated in accordance with decontamination procedures described in GEI’s SOP’s (Appendix D). Quality Assurance/Quality Control (QA/QC) samples will include blind duplicate soil samples, matrix spike/ matrix spike duplicate (MS/MSD) samples, and equipment rinsate blank samples. The quality control samples will be completed at on a frequency of 1/20 or once per week of sampling. Severn Trent Laboratories (STL), an approved New York State ELAP laboratory will perform the analyses. One trip blank will be included per shipment of samples to the laboratory. 3.3.3 Soil Borings and Monitoring Wells GEI will mobilize to the site and conduct the soil borings and monitoring well installations located on Plate 1. Table 1 provides a sample description, rationale, and analysis. Forty-four borings and monitoring wells will be drilled with hollow-stem auger and/or resonant sonic (sonic) drilling methods and split-spoon/core barrel sampling methods as described below. The number and location of the borings and wells are generally based on the technical scope of work proposed by D&B, the subsequent comments received by the City and their consultant, and the NYSDEC comments. However, GEI has departed from the methodology in the D&B proposed scope that specified the use of direct push technology for soil borings and groundwater probes. The D&B proposal specified drilling to the water table (about 10 to 20 feet bgs). GEI proposes to conduct deeper (30 to 40 feet bgs) borings to maintain consistency with the NYDEC


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Draft RI guidance. Specifically, the proposed depth of each boring/well is based on existing hydrogeologic information that indicates an organic muck or peat layer that may be below the water table. This layer is underlain by a “clayey till” reported to be over 100 feet thick. Therefore the objective of this boring program has been expanded to include assessment of the peat to the top of the clayey till layers. Soil samples will be collected continuously through split-spoon/core barrel sampling methods at each boring location. If HSA drilling is conducted, split spoon samples will be collected ahead of the lead auger flight. Upon collection of each split spoon sample, the lead auger will be advanced over the sampled interval prior to collection of the next split spoon sample. This method will ensure that “double-spooning” ahead of the augers does not occur. In addition, while the augers are being advanced a temporary plug will be placed at the bottom of the lead auger to minimize or eliminate the potential for formation materials to run up into the augers. The use of an auger plug will help assure that split spoon samples are representative of in-situ formation materials. Split spoons will be decontaminated manually between each sample interval according to the procedures presented in Appendix D. Hollow stem augers and down-hole drill rods or sonic core barrels will be steam-cleaned at the decontamination pad prior to use and between each boring. Sonic outer casing will be pressure washed as it is extracted. Outer casing with visible impacts will be steam cleaned. Three soil samples will be selected for analysis from each boring. Two separate depth intervals indicating the greatest degree of contamination will be sampled to evaluate the magnitude of the observed impacts at each boring. In addition, a sample from beneath the observed impacted intervals will also be analyzed to assess the vertical extent of the observed impacts. It is anticipated that drilling will proceed approximately 10 feet into a visually un-impacted zone. Each sample will be analyzed for VOCs, SVOCs, RCRA metals, and total cyanide. If a boring exhibits the presence of dense non-aqueous phase liquid (DNAPL), drilling will proceed until signs of the free and residual product are no longer visible. Any deep drilling through nearby impacted zones will ensure that there is no vertical communication caused by the drilling. Specifically, the upper impacted units would be cased and grouted into a lower, more confining unit. Six boring locations will be advanced through the slab inside the warehouse building on Parcel III. A small diameter penetration through the slab floor will be conducted using a Geoprobe™ drill rig. The drilling will be advanced approximately 20 feet to assess the presence or absence of soil impacts. Two soil samples will be collected from each boring and will be analyzed for VOCs, SVOCs, RCRA metals, and total cyanide. The borings will be backfilled with a soil gas


17

probe installed approximately 5 feet below the floor slab. The floor surface will be sealed with concrete. The boring locations will be located as close as practicable to the former MGP and industrial structures that once occupied the site. Actual drilling locations will be driven by the building configuration and the operations of the current tenant. The soil gas points will be allowed to stabilize for at least two weeks prior to sampling for VOCs and naphthalene. Concurrent with the soil gas sampling Method TO-14 VOC analysis using SUMMA canisters will be conducted at the six locations. Twelve of the borings will be completed as groundwater monitoring wells. The well locations are shown in Plate 1. If DNAPL is encountered, up to four additional deep wells will be installed to a maximum of 100 feet bgs, or 10 feet below any signs of contamination, whichever comes first. These deep wells will be installed at locations next to the shallow wells. Groundwater monitoring wells were installed as part of a previous site assessment. GEI will attempt to locate these wells and assess their construction and condition. If it is determined that an existing well meets the objectives of this field program, it may be substituted for a proposed well. The shallow wells will be drilled with 4.25-inch-hollow-stem augers or 6-inch sonic outer casing. The shallow wells will be screened in the uppermost portion of the water table aquifer. If signs of light non-aqueous phase liquids (LNAPL) are encountered in the borings, the well screen will extend approximately two feet above the water table. If DNAPL is encountered, the well screen bottom will be installed on top of any observed confining layer that may be retarding the migration of DNAPL. The screen lengths will not exceed 10 feet. If deep monitoring wells are required based upon the vertical extent of DNAPL tar, the monitoring wells may be installed via hollow-stem auger methods, or by sonic drilling methods. The installation method selected for the deep wells will depend on the depth of contamination, the number of anticipated deep wells, and on the physical drilling conditions. If sonic methods are not selected for the initial mobilization, it may be necessary to conduct the deep well installations during a subsequent mobilization to the site, depending on contractor availability. The monitoring wells will be constructed of 2-inch inside diameter (ID), flush-threaded polyvinyl chloride (PVC) screen and solid casing with a two-foot sump. The annular space between the well screen and borehole wall will be backfilled with chemically inert sand to promote sufficient groundwater flow to the well and to minimize the passage of any fine-grained formational material into the well. A bentonite clay seal will be placed above the sand pack. The remaining annular space will be filled to grade with cement/bentonite grout. The bentonite seal will prevent the migration of contaminants to the sampling zone (i.e., screened interval)


18

from the surface and overlying material and will prevent cross-contamination between strata. Each monitoring well will be fitted with a stick-up or flush-mounted curb box secured with cement. The location of the borings and the proposed analysis are shown in Plate 1 and Table 1. Each sampling implement will be decontaminated in accordance with decontamination procedures described in GEI’s SOP’s (Appendix D). Quality Assurance/ Quality Control (QA/QC) samples will include blind duplicate soil samples, matrix spike/ matrix spike duplicate (MS/MSD) samples, and equipment rinsate blank samples. The quality control samples will be completed at on a frequency of 1/20 or once per week of sampling. Severn Trent Laboratories (STL), an approved New York State ELAP laboratory will perform the analyses. One trip blank will be included per shipment of samples to the laboratory. 3.3.4 Air Monitoring In accordance with NYSDEC and NYSDOH requirements, a Community Air Monitoring Plan (CAMP) will be implemented at the site during each phase of the intrusive field activities. The objective of the CAMP is to provide a measure of protection for the downwind community (i.e., off-site receptors, including residences and businesses and on-site workers not involved with site RI activities) from potential airborne contaminant releases as a direct result of intrusive RI activities. Air monitoring stations will be set up up-wind and downwind of each intrusive work area (i.e., boring and test pit locations). Volatile organic compounds (VOCs) and respirable particulates (PM-10) will be monitored at the up-wind and downwind stations on a continuous basis. Wind direction will be determined using a wind sock(s) and/or flagging poles installed on site. In addition, to the fixed stations, VOCs, particulates, and cyanide will be monitored in the work zone using hand held equipment. VOCs, particulates, and cyanide will also be monitored around the perimeter of the work zone on a regular basis (hourly) by the GEI air monitoring personnel. VOC vapors will be monitored using a photoionization detector (PID). Particulate dust will be monitored using a Miniram particulate meter. The monitoring equipment for cyanide is yet to be selected, but at a minimum will include Drager® tubes for cyanide. The equipment will be calibrated at least daily. The VOC Monitoring, Response Levels, and Actions are presented in Table 1. The proposed CAMP is presented in Appendix C. 3.3.5 Well Development Development of the newly installed monitoring wells will be performed by alternately surging and pumping, utilizing either a centrifugal or piston pump, for a maximum of 1 hour or until the turbidity of the development water is less than 50 nephelometric turbidity units (NTUs). A field turbidity meter will be used to monitor NTU levels.


19

3.3.6 Waste Disposal Sampling One composite soil sample will be collected from the soil cutting drums and analyzed for Toxicity Characteristic Leaching Procedure (TCLP) VOCs, SVOCs, and metals along with reactivity (cyanide, sulfide), ignitability, corrosivity, and paint filter tests. These analyses are intended to characterize the wastes to determine the appropriate disposal options available. 3.3.7 Groundwater Sampling, Storm Sewer Evaluation, Hydraulic Conductivity A minimum of two weeks following completion and development of all the planned new monitoring wells, groundwater samples will be collected from each newly installed well and each existing well, if any are present. If a substantial dense nonaqueous phase liquid (DNAPL) accumulation is present in any well, then no groundwater sample will be collected for laboratory analysis. If DNAPL is found to accumulate in a well, then the DNAPL will be bailed from the well and the recovery rate of the DNAPL will be assessed. Groundwater purging and sampling of the monitoring wells will be conducted according to the procedures set forth in Low Stress (low flow) Purging and Sampling Procedure for the Collection of Ground Water Samples From Monitoring Wells, published July 30, 1996 by the United States Environmental Protection Agency (EPA) Region. The wells will be purged and sampled at rates that minimize or eliminate significant draw down. Dedicated polyethylene tubing will be used at each well. Water quality will be monitored for pH, temperature, specific conductivity, oxidation-reduction potential (Eh), dissolved oxygen, and turbidity. The tubing volume will be calculated and, upon removal of one tubing volume of groundwater, parameters will be recorded at five-minute intervals to determine well stability. Stability is achieved when pH is within 0.1 standard unit, temperature is within 0.5ºC, Eh is within 10% and specific conductivity is within 10% for three consecutive readings. When stability is attained, samples will be collected from the well. Samples for VOC analysis will be collected using a disposable polyethylene bailer. Samples for all other analyses will be collected directly from the tubing. Groundwater samples will be placed directly into pre-cleaned and appropriately preserved sample containers provided by STL. Groundwater analysis will be conducted according to the schedule outlined in Table 1. In addition to the primary groundwater samples, the following QA/QC samples will be collected. § One trip blank sample per day of sampling § One duplicate sample per 20 groundwater samples § One equipment rinse sample per 20 groundwater samples


20

Each QA/QC sample will be analyzed for VOCs, SVOCs, RCRA metals, total cyanide, and pesticides except the trip blank samples, which will be analyzed only for VOCs. Groundwater elevations will be measured in all monitoring wells and the water level of the Gowanus Canal will be measured at two tidal stages (high and low tides) to determine whether tidal effects influence the groundwater flow directions. The historical structure maps show an apparently inactive Sanitary Sewer Line follows a path northeast to southwest across Parcels I, II and III. It is unknown at this time whether the sewer line is still in place or was removed. Test pits conducted near the sewer should reveal the construction and invert elevations if it is there. If the sewer invert can be determined it will be surveyed relative to the groundwater elevations. If the sewer line contains base flow and a manhole can be accessed on the site, then the elevation of the water in the sewer will also be determined along with the groundwater elevations. 3.3.8 Hydraulic Conductivity Testing GEI proposes conducting in-situ hydraulic conductivity tests (slug tests) at three selected wells. The location of the slug tests will be determined after evaluation of the site lithology. A Standard Operating Procedure (SOP) for in-situ hydraulic conductivity testing is provided in Appendix D. In addition, Shelby tube samples from any suspected confining layers (e.g., the clayey till) will be collected and sent to GEI’s geotechnical laboratory for permeability analysis. 3.4 Step I Fish and Wildlife Impact Analysis GEI will retain an ecological risk assessor experienced in New York to conduct a Step I Fish and Wildlife Analysis (FWIA) for the site. The Step I analysis will be conducted in accordance with the current version of NYSDEC’s Fish and Wildlife Impact Analysis for Inactive Hazardous Waste Sites (FWIA). The general objectives of the Step I assessment are: § Identify the fish and wildlife resources, habitats, cover type, wetland and stream

classifications at the site and in the vicinity § Identify the fauna expected within each cover type and aquatic habitat § Document observations of stress to the site soils and vegetation § Describe the value of habitat to expected fauna § Describe the value of the fish and wildlife resources to humans § Determine whether contaminants are present that potentially could affect the expected

fish and wildlife resources § Recommend whether a Step II FWIA is warranted


21

The findings of the Step I FWIA will be included in the final RI Report. 3.5 Qualitative Human Health Risk Assessment In accordance with direction provided by NYSDEC, a qualitative human health risk assessment will be prepared. This assessment will generally follow the guidelines provided in the November 9, 2000 document, titled New York State Department of Health Qualitative Human Health Exposure Assessment (Appendix 1B to NYSDEC’s Draft Site Characterization and Remedial Investigation Guidance document). In general, the assessment will identify the exposure setting, identify exposure pathways, and will evaluate the fate and transport of the contaminants. The assessment will include text discussions, tables, and graphics depicting the potential exposure pathways. The characterization will include all environmental data gathered pertaining to the RI. The qualitative assessment will identify potential risks for specific potential receptors based on complete pathways of exposure to contaminant levels exceeding default “screening criteria,” such as the NYSDEC-recommended soil cleanup objectives (RSCOs) and drinking water standards. The qualitative risk assessment will not quantitatively evaluate the potential carcinogenic and non-carcinogenic risks to potential receptors. In addition, the qualitative assessment will not evaluate potential alternative risk-based exposure criteria or risk-based cleanup criteria. 3.6 Survey and Sample Point Location Following completion of the planned soil borings, monitoring wells, and collection of the surface-soil samples, each of these points will be surveyed by a New York State Licensed Land Surveyor. The elevation of each new monitoring well will be determined to ±0.01 foot. In addition, a permanent surveyed benchmark will be established at the Gowanus Canal, by which to measure the river elevation. All locations and elevations will be tied to the New York State Plane Coordinate System.. 3.7 Quality Assurance/Quality Control and Data Validation Severn Trent Laboratories will provide New York State Category B data deliverables. The data will be validated in accordance with NYSASP protocols. The data validator will prepare a data usability report summarizing the adequacy of the analytical data obtained from the laboratory and discussing any pertinent data excursions or limitations on the use of the data. The data usability report will be used in preparing the RI report, and will be submitted as part of the RI report. Through the use of standardized sample collection and decontamination procedures (SOPs in Appendix D), the quality of the samples during field collection can be assured.


22

The data validation process will ensure that the data collected and reported by the laboratory are of sufficient quality that management decisions regarding the degree and extent of potential impacts can be reliably made. The data validation will evaluate whether the required quantitation limit has been achieved for each sample analyzed, and will evaluate the precision, accuracy, and completeness of the data. The data validator will use the duplicate samples, the MS/MSD samples, the trip blanks, and the equipment rinsate blank samples, as well as laboratory calibration blanks, spikes, and other standards to assess the quality of the data obtained. Any deviations from the required level of sample quality will be called out in the data usability reports prepared by the data validator and these deviations will be taken into consideration when using the data to explain site conditions.


23

4. RI Report Preparation 4.1 Data Reduction and Data Summary Field observations and empirical data collected during the RI will be analyzed to develop a site conceptual model. A composite base map that accurately illustrates the locations and elevations of site features, including all sampling locations, will be developed. Analytical data will be validated to determine if the data meet acceptable criteria for precision, accuracy, and completeness. Validated analytical data will be tabulated and compared to applicable NYSDEC standards. Field observations will be compared and correlated with the validated analytical data to characterize impacted areas. The conceptual model will be presented in graphical and tabular form. The impacted areas will be illustrated through boring logs, test pit logs, plan view maps, and cross sections. A groundwater flow map will be generated illustrating groundwater flow direction of the overburden aquifer beneath the site. At least two cross sections will be completed to depict the hydrogeology parallel and perpendicular to groundwater flow. All site data will be managed in a database so that the physical and chemical data can be easily integrated and compared to NYSDEC standards. 4.2 RI Report GEI will prepare a RI report for submittal NYSDEC for the Citizens Gas Works site. The reports will incorporate the findings of the RI activities. The information will be used to describe the nature and extent, and fate and transport of all contaminants associated with the former MGP site. The report will identify specific contaminant concentrations throughout each media (e.g., soil, groundwater, etc.), which is necessary to determine whether any media require remediation or further evaluation. The reports will also incorporate the findings of the Step I FWIA and the Qualitative Human Health Risk Assessment. Key components of the RI report will include: § Description of RI activities § Discussion of site geology and groundwater flow patterns § Distribution of analytical compounds in soil and groundwater § Distribution of nonaqueous phase liquid (NAPL) § Identification of historic structures and associated waste source areas § Comparison of site soil and groundwater analytical data to NYSDEC standards


24

§ Identification of areas that exceed the soil and groundwater standards § Boring logs, test pit logs, and monitoring well construction details § Data usability reports § Validated laboratory Form I reports § Site photographs


25

5. Schedule GEI can begin preparation for field mobilization within one week upon receipt of NYSDEC approval of this work plan. Mobilization for field activities can be accomplished within ten days of receipt of NYSDEC approval. However, the commencement of field activities is contingent upon removal of non-MGP debris where field activities will occur and upon availability of subcontractors. It is expected that final NYSDEC approval of this RI work plan will be given by the end of January 2003. Based on this approval date, the soil boring, monitoring well installation, and surface-soil sampling could begin on February 24, 2003 and be completed by April 16, 2003. Groundwater sampling, and hydraulic conductivity testing could be conducted the week of April 28, 2003. Upon validation and compilation of the RI laboratory data, the FWIA and qualitative risk assessment can be started in June 2003 and be completed in July 2003. Report preparation activities would continue through August 2003, at which point GEI will submit a Draft RI Report for KeySpan review and comment. Dependent on NYSDEC review and a presentation of findings meeting in September 2003, final submittal of the final RI Report is expected by November 1, 2003. A detailed project schedule using Microsoft “Schedule” will be prepared. This schedule will incorporate critical path items and contingencies of the site access agreement. The final schedule will be delivered upon approval of this work plan. Revisions will be submitted as needed based upon any changes in field conditions or logistics.


26

6. Project Team GEI’s key project members and their roles are summarized below. § David Terry – KeySpan Program Manager. Mr. Terry will have ultimate

responsibility for successful completion of the work scope, will interface with KeySpan as needed, and will be responsible for project quality control.

§ Fred Johnson – Project Manager. Mr. Johnson will have the day-to-day responsibility

for project logistics, coordination with the KeySpan, NYDEC, and the City. He will be responsible for the deliverables and quality control

§ Dennis Unites – In-House Consultant. Mr. Unites will serve as GEI’s in-house

consultant for the project team. Mr. Unites’ extensive MGP experience and understanding of MGP historic operations, and the behavior of MGP contaminants in the environment, are a valuable asset to the project team.

§ Matt O’Neil – Lead Engineer. Under the direction of Mr. Johnson, Mr. O’Neil will be

primarily responsible for implementation of the field program, managing GEI’s subcontractors, interpretation of the investigation findings, and preparation of the RI report.

KeySpan Energy Corporation Remedial Investigation Work Plan

Table

Citizens Works Former MGP SiteCarrol Gardens, New York

Parcel I - Proposed Sampling Plan

Sample Sample Sample Number of Samples VOC's Metals Cyanide SVOCs PesticidesI.E. Location Rationale Soil Groundwater EPA 8260 RCRA 8 Total EPA 8270 EPA 81414 PCB

Surface Soil Samples (to be collected after all surface debris removal is complete)SS Parcel I around the former gas

holders 0-2"Assess surface impacts from former MGP gas holders

4 4 4 4 4 4 4

SS From any soil stockpiles remaining after debris removal from Parcel I, random sample from pile

Assess residual soils distributed during debris removal

4 4 4 4 4 4 4

SS Ambient surface soils across Parcel I, 0-2"

Collected after debris removal to assess residual surface conditions

5 5 5 5 5 5 5

Test Pit Samples - (conducted prior to borings)TP Edge of the 4 former gas holder

foundations, sample collection based upon field observations

Assess the location, depth, configuration and contents of the former holders

5 5 5 5 5 5 5

TP At the location of several former Assess the potential for these 12 12 12 12 12 12 12MGP structures structures to be a release area• Generator house and/or for them to control• Tar extractors subsurface migration• Purifying house #1 and #2• Oil tank cluster• Oil tanks 10 & 11• Condenser• Abandoned drum area• Skip hoist• MGP scrubbers and pump house• Along 6' sewer line

SB • Holders 1, 2, 3, and 4 Assess content and any 12 12 12 12 12 4 locations vertical migration under holders

GW • Condensers Downgradient assessment 3 3 3 3 31 1 1 1 1 1

SB • Still house Assessment of soils 3 3 3 3 3

GW • Oil tanks Downgradient assessment, 3 3 3 3 3soils and groundwater 1 1 1 1 1 1

SB/GW • Scrubbers/purifier Downgradient assessment of 6 6 6 6 6 house, 2 borings, one well groundwater and assessment 1 1 1 1 1 1

of soil around structure

Soil and Groundwater Assessment

Page 1 of 5 J:\WPROC\Dbt\KEYSPAN\Citizens Gas Works\RI Work Plan\PropSamplPlanTbl.xls


Parcel I - Proposed Sampling Plan


SB/GW • South purifier house Downgradient assessment of 6 6 6 6 6 2 borings, one well groundwater and soils in 1 1 1 1 1 1

structureSB • Generator house Assessment of soils in 3 3 3 3 3

structureSB • Oil tanks 10 and 11 Assessment of soils 6 6 6 6 6

SB • Southeastern corner of parcel Downgradient of sewer and 3 3 3 3 3 near pump house most downgradient on the

parcelGW • Norwest corner of Parcel 1 Upgradient well 3 3 3 3 3

1 1 1 1 1 1

SD • 4 locations in canal adjacent Assess sediment impacts 8 8 8 8 8 8 8 site showing visual impacts adjacent to the site

SD • 2 locations, one upstream, Assess sediment impacts 4 4 4 4 4 4 4 one downstream upstream and downstream

from the site

Shallow Soil and Groundwater Assessment - (continued)

Gowanus Canal Sediment Sampling



Parcel II - Proposed Sampling Plan


Surface Soil Samples (to be collected after all surface debris removal is complete)SS 4 locations in undeveloped areas

of the site 0-2" deepAssessment of ambient exposed soil quality

4 4 4 4 4 4 4

Test Pit Samples - (conducted prior to borings)TP 5 locations along edge of

Gowanus canal, one soil sample per test pit

Assess the presence of any MGP residual behind the canal wall. Sample location based on field screening

5 5 5 5 5 5 5

TP • Along 6 foot sewer Assess sewer as a potential migration pathway

1 1 1 1 1 1 1

GW • Northwest corner of site Upgradient Parcel II, 3 3 3 3 3downgradient holder 5 1 1 1 1 1 1

GW • Condenser/catch basin Assess for impacts 3 3 3 3 3downgradient 1 1 1 1 1 1

SB • Coal trestles Vertical profile along Gowanus 3 3 3 3 3canal wall

GW • Dump shaft Vertical profile along Gowanus 3 3 3 3 3canal wall, downgradient on site 1 1 1 1 1 1

SB • Settling tanks Assess for MGP residuals 3 3 3 3 3

Soil Borings and Groundwater Monitoring Wells



Parcel III - Proposed Sampling Plan


Surface Soil Samples (to be collected after all surface debris removal is complete)SS 4 undeveloped areas on Parcel

III, 0-2" deepAssessment of ambient exposed soil quality

2 2 2 2 2 2 2

Test Pit Samples - (conducted prior to borings)TP 6 locations

• 4 along seawall Assess for MGP buildup behind the seawall.

4 4 4 4 4 4 4

• Settling tanks and separator 1 1 1 1 1 1 1• Tar storage tanks 1 1 1 1 1 1 1

GW • 2 along seawall Downgradient of former MGP 6 6 6 6 6structures, vertical profile along 2 2 2 2 2 2seawall

GW • Southern property line Downgradient of warehouse 3 3 3 3 3and former coal storage 1 1 1 1 1 1

SB • 2 locations at former tar Assess vertical soil impacts 6 6 6 6 6 separators and settling tanks near MGP structures

Soil Borings and Groundwater Monitoring Wells



Parcel IV - Proposed Sampling Plan


Surface Soil Samples (to be collected after all surface debris removal is complete)SS 2 locations next to Holder #5 Assess ambient surface soil

quality2 2 2 2 2 2 2

Test Pit Samples - (conducted prior to borings)TP Edges of Holder #5 Assess the contents and

construction of the former holder2 2 2 2 2 2 2

SB Downgradient side of Holder #5 Assess vertical soil and groundwater quality

3 3 3 3 3

SB Inside holder #5 Assess construction and 3 3 3 3 3content of holder

GW Upgradient of holder #5 Most upgradient site well 3 3 3 3 31 1 1 1 1 1

Vertical Soil and Groundwater Assessment



Figure


Plate

EAST SHAFT

FIREPROOF TUNNEL

FOR GAS PIPE LINES

DUMP

RUNWAY

PUMP

HOUSE

PUMP

HOUSE

HOT

WATER

TAR SETTLING

TANK

SEPARATOR

STORAG

E

SHED

STO

RAG

E

TAR STORAGE

TANKS

STORAGE

PLATFORM

FORMER COAL

STORAGE AREA

~ ~

~

~

W. HOUSE

STORAGE SHEDS

BINSBINS

PURIFYING HOUSE

OIL TANKS

PURIFYING HOUSE

EXHAUSTER HOUSE

CONDENSER

CONDENSER HOLDER NO. 4

BOIL

ER

HO

USE

GENERATOR HOUSE

CATCH

BASIN

CATCH

BASIN

CATCH

BASIN

OIL TANK

NO. 10

OIL TANK

NO. 11

OIL TANK

NO. 2

SCALE

SKIP

HOIST

HOPPER

BLO

WER

S

COAL

TRESTLES

COAL

HOPPER

WATCHMAN'S

HOUSE

GOVERNOR

HOUSE

ENGINE

ROOM

CO

NDE

NSER

CATCH

BASIN

STORAGE

ROOM

OIL

ROOM

PIPE

RACK

STORE

ROOM

SETTLING

TANK

FIRE

APTS.

TAR EXTRACTORS

HOLDER NO. 3

HOLDER NO. 2

HOLDER NO. 1

STILL

HOUSE

LAB

PUMP

HOUSE

PURIFICATION

TOWERS

PUMP

TANKS

SEAL

POTS

SCRU

BBE

RS

COAL HOIST

& CRUSHER

STORAGE

SHED

HOLDER NO. 5

OIL TANK

STORAGE

ROOM

PHOSPHATE

ROOM

MIXING ROOM

GRINDING ROOM

CRYSTALIZING

ROOM

REFINING

ROOM

FORMER SEVENTH STREET

FORMER SIXTH STREET

RESIDENTIALSEPARATING

HOUSEOIL TANK

OILTANKS

OIL PUMP

HOUSE

SHED

SHED

CONDENSERS

COAL

TRESTLES

WATER

PUMPS

HOPPERS

CEMENT

MIXER

OFF

ICE

COAL CONVEYOR ON TRESTLE

SIXTH STREET BASIN

GOWANUS C

ANAL

HUNTINGTON STREET

NELSON STREET

SM

ITH

S

TRE

ET

HO

YT

S

TREE

T

FIFTH STREET

6' SEWER

CARROLL GARDENS IIIPARCEL

CARROLL GARDENS IPARCEL

CARROLL GARDENS IVPARCEL

CARROLL GARDENS IIPARCEL

DEBRIS TO BE REMOVED

DEBRIS TO BE REMOVED

CONSTRUCTION OFFICE

DEBRIS STOCKPILE AREA

AREA C

AREA B

AREA A

AREA D

GATE LOCATION

GATE LOCATION

TEMPORARY CONSTRUCTION FACILITIES

GATE LOCATION

6"

TREE TO BE REMOVED

TEMPORARY ACCESS ROAD

TEMPORARY ACCESS ROAD

TEMPORARY HEAVY EQUIPMENT STORAGE AREA

Warehouse

Concrete Plant

SEVENTH

STREET BASIN

GW

GW

GW

GW

GW

GW

GW

GW

GW-5

GW-4

GW-3

SB

SB

SB

SB

SB

SB

SB

SB

SB

SB

SB

SB

SB

SB

GW-2

MW

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS

SS (4) SOIL

SS

SS

SS

SS (2) SURFACE

SS

SS

GW

GW

SB

SB

GW-6

GW

SB

TP

TP

TP

TP

TP

TP

TP

TP

TP

TP

TP

TP

TP

TP

TP

SB

SB

SB

SB

SB

SB

SB

SB SB

SB

SB

SB

SB

TP

TP

TP

TP

SB

SB

SB

SB

SB

SB

SB

SB

APPROXIMATE BOUNDARY OF FORMER MGP SITE

CURRENT STRUCTURE

HISTORICAL STRUCTURE

AREA BOUNDARIES

SURFACE CONTOUR (FT)

SECURITY FENCE

PROPOSED SOIL SAMPLE LOCATION (21 TOTAL)

PROPOSED TEST PIT LOCATION (19 TOTAL)

PROPOSED SOIL BORING LOCATION (32 TOTAL)

PROPOSED SOIL BORING WITH GROUNDWATER MONITORING WELL LOCATION (12 TOTAL)

EXISTING GROUNDWATER WELL LOCATION (APPROXIMATE)

PROPOSED SOIL GAS GEOPROBE LOCATION (6 TOTAL)

LEGEND

NOTE: 4 SOIL BORINGS (SB) WILL BE COMPLETED AS GROUNDWATER WELLS DEPENDING ON FIELD CONDITIONS

SS

SB

MW

MW-1

TP

SB

DRN BY:

DATE:

SCALE:

PREPARED FOR

CITIZENS GAS WORKS FORMER MGP SITE

KEYSPAN

CARROLL GARDENS, BOROUGH OF BROOKLYN, NEW YORK

1"=40'

JAN 2003

PHH

PROPOSED SAMPLE LOCATIONS

PLATE 1KEYSPAN\CITIZENS\1901\PLATE\CIT-SAMP REV 1-31-03

GRAPHIC SCALE IN FEET

050 25 50 100

NOTES:

A. Site has been separated into 4 operating areas (A,B,C, and D). These areas represent a sequential clearing of the site to facilitate construction activities.

B. Type 1 backfill materials shall meet the requirements of Coarse Aggregate, material designation 703-0201 (Crushed Stone), size designation 3A in accordance with the Standard Specifications, Construction and Materials, including Addendum No. 1, prepared by the Office of Engineering, New York State Department of Transportation, Latest Revision.

1. Type 1 Backfill materials shall conform the following gradation requirements. U.S. Standard Sieve Size Percent Passing by Weight 2 inch 100 1.5 inch 90 to 100 1 inch 0 to 15

2. Type 1 Backfill materials shall have a pH greater than 5 and less than 10.

Area A: Temporary Construction Facilities: This area shall be cleared of all shrubs, trees, and debris. Area shall be covered with 1.5" of Type I backfill.Temporary Access Road: All road locations are approximate and will be installed based on site conditions and exact locations of access gates. The road shall be cleared of all shrubs, trees, and debris to a nominal width of 20' feet and graded to accommodate access by wheeled vehicles and heavy equipment from the City of New York Department of Design and Construction (DDC), KeySpan Energy, Inc. (KeySpan), and their subcontractors. Road shall be covered with 1.5' of Type I backfill, as needed.Debris Stockpile Area: This area shall be available to the City of New York DDC for staging of on-site debris. The area shall be enclosed on three sides with nominally 2' x 2'x 4' concrete blocks (minimum 2 high) to prevent damage to site security fencing and prevent any potential off-site exposure to on-site debris.

Area B: Temporary Access Road: All road locations are approximate and will be installed based on site conditions and exact locations of access gates. The road shall be cleared of all shrubs, trees, and debris to a nominal width of 20' feet to accommodate heavy equipment from the City of New York DDC, KeySpan, and their subcontractors. Road shall be covered with 1.5' of Type I backfill, as needed.

Area C:Temporary Heavy Equipment Staging Area: Staging area location is approximate and will be installed based on site conditions and exact locations of access gates. The staging area shall be cleared of all shrubs, trees, and debris to accommodate staging of heavy equipment from the City of New York DDC, KeySpan, and their subcontractors. Staging area shall be covered with 1.5' of Type I backfill, as needed.

Area D:Access to Area D will be on a location by location basis, as necessary, and will be coordinated between the City of New York DDC and KeySapn as required during the site investigation activities.

DRAFT


Appendix A

Previous Site Data


Appendix B

Severn Trent Laboratories – Connecticut, Quality Assurance Project Plan


Appendix C

Community Air Monitoring Program

Community Air Monitoring Plan Citizen’s Gas Works

Former Manufactured Gas Plant Site In accordance with NYSDEC and NYSDOH requirements for a Community Air Monitoring Plan (CAMP), a perimeter air-monitoring plan, will be implemented at the site during each phase of the field activities. The objective of the perimeter air-monitoring plan is to provide a measure of protection for the downwind community (i.e., off-site receptors, including residences and businesses and on-site workers not involved with the site field activities) from potential airborne contaminant releases as a direct result of field activities. The perimeter air-monitoring plan is a stand-alone document and will be available on site. The VOC Monitoring, Response Levels, and Actions are presented as follows.

Air Monitoring Response Levels and Actions

VOCs Response Level Actions

>5 ppm above background for 15-minute average

§ Temporarily halt work activities § Continue monitoring § If VOC levels decrease (per instantaneous readings) below 5 ppm over background, work

activities can resume

Persistent levels >5 ppm over background <25 ppm

§ Halt work activities § Identify source of vapors § Corrective action to abate emissions § Continue monitoring § Resume work activities if VOC levels 200 feet downwind of the property boundary or half the

distance to the nearest potential receptor is <5 ppm for a 15-minute average § If VOC levels are >25 ppm at the perimeter of the work area, activities must be shutdown

Particulate >100 mcg/m3 above background for 15-minute average or visual dust observed leaving the site

§ Apply dust suppression § Continue monitoring § Continue work if downwind PM-10 particulate levels are <150 mcg/m3 above upwind levels

and no visual dust leaving site

>150 mcg/m3 above background for 15-minute average

§ Stop work § Re-evaluate activities § Continue monitoring § Continue work if downwind PM-10 particulate levels are <150 mcg/m3 above upwind levels

and no visual dust leaving site

Sources: New York State Department of Health Community Air Monitoring Plan, June 20, 2000. New York State Department of Environmental Conservation Division Technical and Administrative Guidance Memorandum - Fugitive Dust Suppression and Particulate Monitoring Program at Inactive Hazardous Waste Sites, October 27, 1989.

During excavating and materials handling operations, the air in work areas will also be sampled periodically for the presence of contaminants. A portable photoionization detector (PID) will be utilized to periodically monitor the levels of organic vapors in the ambient air and a Mini RAMTM PM-10 (or equivalent) particle detector will be used to count inhalable particles (0.1-10 micrometer range) of dust during the field work. PID and Mini RAM readings will be taken hourly during excavation or more frequently if air quality measurements approach action levels as defined herein. Measurements will be monitored from the breathing zone (4 to 5 feet above ground level) at worker locations to determine working conditions (and whether there is a need to change levels of worker protection). In addition to VOCs and particulates, cyanide will be monitored in the work zone and at the perimeter of the work area. The cyanide monitoring methods will be determined prior to mobilization, but at a minimum, will include Drager® tube sampling. In order to make a conservative assessment of when different levels of respiratory protection are needed during the field work, it will be assumed that the organic vapors detected by the air monitoring instruments consist of the most toxic volatile compounds expected to be found on the site. Preliminary evaluation of the risks expected at the site indicates that the most toxic volatiles that are probably present are VOCs (particularly BTEX). Based on data published by the Occupational Safety and Health Administration (OSHA) and the American Conference of Government Industrial Hygienists (ACGIH), and GEI’s experience with MGP wastes, the following PPE will be employed when the given concentrations of organic vapor are detected in the breathing zone.

Compound of Concern Level D Level C Level B Chemical Name M<X X<M<Y M>Y BTEX and other photoionizable VOCs M <5 ppm 5 ppm <M <50 ppm M >50 ppm

Where: M = concentration of organic vapor measured in the field X,Y= concentrations at which different levels of respiratory protection are necessary.

The PPE requirements may be modified based on compound-specific monitoring results information, with the written approval of the Corporate Health and Safety Specialist (CHSS). Respiratory protection from dusts will be required when inhalable particulate concentrations from potentially contaminated sources exceed 150 µg/m3. Odors or dusts derived from site contaminants may cause nausea in some site workers, even though the contaminants are at levels well below the safety limits as defined above. Workers may use dust masks or respirators to mitigate nuisance odors with the approval of the SSO. Whenever practical, work areas should be positioned upwind of organic vapor and dust sources to reduce the potential for worker exposure.


Appendix D

GEI Standard Operating Procedures

Remedial Investigation Work Plan

Documents

Transcript of Remedial Investigation Work Plan