FEASIBILITY STUDY FOR THE NEW YORK CITY SCHOOL CONSTRUCTION AUTHORITY PILOT STUDY TO ADDRESS PCB CAULK IN NEW YORK CITY SCHOOL BUILDINGS

Transcription

1 FOR THE NEW YORK CITY SCHOOL CONSTRUCTION AUTHORITY PILOT STUDY TO ADDRESS PCB CAULK IN NEW YORK CITY SCHOOL BUILDINGS EPA CONSENT AGREEMENT AND FINAL ORDER DOCKET NUMBER: TSCA SCA LLW NO.: SCA CONTRACT NO.: C SCA JOB NO.: TRC ENGINEERS, INC. PROJECT NO.: January 31, 2011 Prepared by: Prepared for: TRC Engineers, Inc. NYC SCA 1430 Broadway, 10th Floor Thomson Avenue New York, NY Long Island City, NY Phone: (212) Phone: (718) Fax: (212) Fax: (718)

2 TABLE OF CONTENTS Section Page EXECUTIVE SUMMARY... VII 1.0 INTRODUCTION Purpose Background Relevant Schools Overview of Remedial Investigations Applicable Comparison Criteria Nature and Extent of PCB Caulk PCB Caulk Fate and Transport USEPA Defined Areas to be Evaluated in Each Pilot School Building Scope of Pilot Study Summary of Findings and Recommendations of the Pilot Study DESCRIPTION OF THE REMEDIAL ALTERNATIVES Introduction Remedial Objectives General Scope of Response Actions Description of Individual Remedial Alternatives Evaluated Patch and Repair of All Damaged and Deteriorated PCB Caulk Encapsulation of All PCB Caulk Removal of All PCB Caulk and Replacement with New Caulk Window Removal and Replacement Removal and Replacement of PCB Light Ballasts and Fixtures Best Management Practices Remediation of Surface Soils in Outside Exposure Areas COST ANALYSIS OF PILOT STUDY REMEDIAL ALTERNATIVES Cost Analysis of Patch and Repair Remedy Description of Work Performed Labor Transportation and Disposal Summary of Contractor Costs Amount of PCB Caulk Remediated Cost to Remediate PCB Caulk TRC ENGINEERS, INC. i

3 TABLE OF CONTENTS Section Page 3.2 Cost Analysis of Removal and Replacement Remedy Description of Work Performed Labor Transportation and Disposal Summary of Contractor Costs Amount of PCB Caulk Remediated Cost to Remediate PCB Caulk Cost Analysis of Encapsulation Remedy Description of Work Performed Labor Transportation and Disposal Summary of Contractor Costs Amount of PCB Caulk Remediated Cost to Remediate PCB Caulk Cost Analysis of Window Removal and Replacement Remedy Description of Work Performed Labor Transportation and Disposal Summary of Contractor Costs Amount of PCB Caulk Remediated Cost to Remediate PCB Caulk Cost Analysis of Light Fixture Ballast Removal and Replacement Remedy Description of Work Performed Labor Transportation and Disposal Summary of Contractor Costs Number of PCB Light Ballasts/Fixtures Remediated Cost to Remediate PCB Light Ballasts/Fixtures Cost to Remediate Outdoor Exposure Areas P.S. 178X/ P.S. 199M P.S. 309K Cost Analysis Discussion TRC ENGINEERS, INC. ii

4 TABLE OF CONTENTS Section Page 4.0 INDIVIDUAL ANALYSIS OF REMEDIAL ALTERNATIVES Introduction Patch and Repair Remedy Description Assessment Overall Protectiveness Compliance with Comparison Criteria Long-Term Effectiveness and Permanence Reduction of Toxicity, Mobility or Volume Through Treatment Short-Term Effectiveness Ease of Implementation Cost Encapsulation Description Assessment Overall Protectiveness Compliance with Comparison Criteria Long-Term Effectiveness and Permanence Reduction of Toxicity, Mobility or Volume Through Treatment Short-Term Effectiveness Ease of Implementation Cost Removal and Replacement Description Assessment Overall Protectiveness Compliance with Comparison Criteria Long-Term Effectiveness and Permanence Reduction of Toxicity, Mobility or Volume Through Treatment Short-Term Effectiveness Ease of Implementation Cost TRC ENGINEERS, INC. iii

5 TABLE OF CONTENTS Section Page 4.5 Window Removal and Replacement Description Assessment Overall Protectiveness Compliance with Comparison Criteria Long-Term Effectiveness and Permanence Reduction of Toxicity, Mobility or Volume Through Treatment Short-Term Effectiveness Ease of Implementation Cost PCB Light Fixture and Ballast Replacement Description Assessment Overall Protectiveness Compliance with Comparison Criteria Long-Term Effectiveness and Permanence Reduction of Toxicity, Mobility or Volume Through Treatment Short-Term Effectiveness Ease of Implementation Cost Best Management Practices Description Assessment Overall Protectiveness Compliance with Comparison Criteria Long-Term Effectiveness and Permanence Reduction of Toxicity, Mobility or Volume Through Treatment Short-Term Effectiveness Ease of Implementation Cost TRC ENGINEERS, INC. iv

6 TABLE OF CONTENTS Section Page 4.8 Soil Removal in Outside Exposure Areas Description Assessment Overall Protectiveness Compliance with Comparison Criteria Long-Term Effectiveness and Permanence Reduction of Toxicity, Mobility or Volume Through Treatment Short-Term Effectiveness Ease of Implementation Cost PROPOSED PILOT PREFERRED REMEDY REFERENCES LIST OF TABLES (WITHIN TEXT) Table 1.1 Summary of Pilot School Buildings Table 1.2 USEPA s Public Health Levels of PCBs in School Indoor Air Table List of 2010 Remediated Areas: PCB Caulk Patch and Repair for P.S. 178X/176 Table List of 2011 Remediated Areas: PCB Caulk Patch and Repair for P.S. 178X/176 Table List of 2011 Remediated Areas: PCB Caulk Removal and Replacement with New Caulk for P.S. 199M Table List of 2010 Remediated Areas: PCB Caulk Encapsulation for P.S. 309K Table List of 2011 Remediated Areas: PCB Caulk Encapsulation for P.S. 309K Table 3.6 Cost Comparison of Interior Remedial Alternatives Table Cost Comparison of Exterior Remedial Alternatives TRC ENGINEERS, INC. v

7 LIST OF FIGURES Figure 1A P.S. 178X/176 Site Location Map Figure 2A P.S. 199M Site Location Map Figure 3A P.S. 309K Site Location Map Figure 4A P.S. 183Q Site Location Map Figure 5A P.S. 3R Site Location Map LIST OF APPENDICES A. Figures B. Individual Analysis of Remedial Alternatives C. List of Relevant Schools D. SCA Specification Section PCB-Containing Caulk Removal Work E. SCA PCB Ballast Inspection and Response Project Plan F. Best Management Practices (BMP) for PCB Caulk in New York City School Buildings G. Pilot Study Remedial Alternative Cost Analyses H. Encapsulant Manufacturer s Cut Sheets and Material Safety Data Sheets I. Remedial Investigation Plan Dust Control J. Soil Sampling Procedures TRC ENGINEERS, INC. vi

8 EXECUTIVE SUMMARY The New York City Division of School Facilities (DSF) and School Construction Authority (SCA) currently implement a PCB Program that includes protocols to properly manage PCB Caulk in public schools and during capital improvement projects. On January 19, 2010, The City of New York (the City) and SCA reached an agreement regarding the assessment and remediation of PCB Caulk in public school buildings with the United States Environmental Protection Agency (USEPA), Region 2 (Consent Agreement and Final Order (CAFO), Docket Number TSCA ). As a result of the agreement, the City is undertaking a comprehensive Pilot Study to evaluate the possible presence of PCB Caulk and preferred remedial alternatives. Where necessary, the Pilot Study also evaluated non-caulk sources of PCBs, such as light ballasts. The ultimate goal of the CAFO is to develop a Citywide PCB Management Plan for the relevant schools (built between 1950 and 1978). The agreement required the City to select, and USEPA to approve, five Pilot School Buildings from the list of relevant schools. The five approved Pilot School Buildings are P.S. 178X/176 in the Bronx, P.S. 199M in Manhattan, P.S. 309K in Brooklyn, P.S. 3R in Staten Island, and P.S. 183Q in Queens. A Pilot Study was developed and implemented to test and evaluate selected remedial strategies in these Pilot School Buildings. The study was performed in accordance with the Remedial Investigation (RI) Plan dated July 9, 2010 and the Addendum No.1 to the RI Plan dated July 19, 2010 (approved by USEPA on August 12, 2010), and the modification dated November 23, 2010 (approved by USEPA on November 29, 2010). The study was also performed in accordance with recommendations presented in TRC s Interim Remedial Investigation Report (IRIR) dated June 15, 2011 (approved by USEPA on August 30, 2011). The purpose of these studies was to assist in identifying a preferred remedy or remedies for PCB Caulk and PCB light ballasts in public school buildings. The remedial alternatives selected, in consultation with the USEPA, for evaluation during the Pilot Study and the Feasibility Study included: (1) Patch and repair of caulk (i.e., remove loose and deteriorating caulk and replace with new non PCB-containing caulk); (2) Encapsulation of caulk; (3) Removal of all caulk and replacement with new non PCB-containing caulk; (4) Window frame and caulk removal and replacement with new window frames and non PCBcontaining caulk; (5) PCB light ballast and fixture removal; and, (6) Best management practices (i.e., use pre-remedial baseline sampling data to evaluate the effectiveness of current operation and maintenance practices). Remedial alternatives (1), (2), and (3) were evaluated in three Pilot School Buildings - P.S. 178X/176, P.S. 309K, and P.S. 199M, respectively. Remedial alternative (4) was evaluated in P.S. 183Q. Remedial alternative (5) was evaluated in P.S. 3R. Remedial alternative (6) was also evaluated in each of the five Pilot School Buildings through the evaluation of the pre-remediation sampling data. The Pilot Study was implemented in two primary phases. In the first phase, which was conducted from June 2010 through November 2010, the SCA implemented a remedial investigation of three Pilot School TRC ENGINEERS, INC. vii

9 Buildings (P.S. 178X/176, P.S. 199M, and P.S. 309K) in accordance with the CAFO and the RI Plan. The scope, results, findings and recommendations of these initial remedial investigations are presented in the IRIR dated June 15, 2011, and Addendum No. 1 to the Report dated October 5, 2011, which the USEPA approved in its letter dated October 20, As presented in the subsequent RI report, the second phase of the Pilot Study occurred from April 2011 through October Whole-school remedies consistent with the first phase remedies were implemented in P.S. 178X/176, P.S. 199M, and P.S. 309K. In addition, two additional schools were studied under the Pilot Study to evaluate other remedial alternatives: light ballast and fixture removal was evaluated in P.S. 3R and window removal and replacement was evaluated in P.S. 183Q. Based upon post-remedial air sample results, additional postpilot remedial efforts were also undertaken in 2011 in all five of the Pilot School Buildings except P.S. 178X/176. As part of the RI Report, this Feasibility Study (FS) has been prepared to present the results of an evaluation of the potential remedial actions based on the Pilot Study results completed to date at these five Pilot School Buildings. Included in the FS is an evaluation of the individual remedial alternatives in order to aid in the selection of the most appropriate remedy. The individual analysis examines the performance of each alternative against seven evaluation criteria highlighting the specific strengths and weaknesses relative to each evaluation criterion. A matrix summarizing the results of the evaluation of the remedial alternatives against the evaluation criteria is included in Appendix B. These criteria are designed to allow the analysis of each alternative to address all the statutory requirements and considerations in order to select the most appropriate remedial alternative. The proposed Pilot Preferred Remedy, as supported by the companion Remedial Investigation Report, is as follows: The Pilot Study evaluated five remedial alternatives with respect to interior caulk: (1) Patch and repair of caulk at P.S. 178X/176; (2) Encapsulation of caulk at P.S. 309K; (3) Removal of all caulk and replacement with new non PCB-containing caulk at P.S. 199M; (4) Window frame and caulk removal and replacement with new window frames and non PCB-containing caulk at P.S. 183Q; and (5) Best Management Practices at all Pilot School Buildings. Based on the current data, each of these alternative remedial approaches has been shown to be effective at reducing potential exposures to interior PCB caulk in the Pilot School Buildings. Thus, the alternative remedial approaches implemented at each Pilot School Building for interior caulk should remain in place and continue to be evaluated pursuant to the USEPA-approved long-term monitoring plan. The Pilot Study determined that the replacement of PCB light ballasts and associated fixtures is a successful remedial measure for lowering PCB levels in indoor air where concentrations exceed the USEPA air guidance values. Light fixture replacements were implemented at P.S.309K, P.S. 178X/176, and P.S. 199M as supplemental remedial measures, and at P.S. 3R as the primary remedial measure. Light fixture replacement is effective where a supplemental remedy is necessary, and also as a primary remedial measure. Thus, the Pilot Preferred Remedy includes light fixture replacement at the Pilot School Buildings. Light fixture replacement will be implemented at P.S. 183Q in accordance with the Greener, Healthier Schools for 21st Century and Energy Savings Performance Contracting (ESPC) program. PCB contamination of soil encountered in Outside Exposure Areas at P.S. 199M, P.S. 178X/176 and P.S. 309K was successfully mitigated through the process of delineation, excavation, and offsite disposal. The PCB contaminated soil identified in the outdoor exposure areas at P.S. 183Q TRC ENGINEERS, INC. viii

10 and P.S. 3R should be excavated and disposed utilizing these same protocols. Create a Soil Remediation Plan for USEPA approval and remediate soils above 1 part per million (ppm) by excavation and off-site disposal, and obtain confirmatory post-excavation soil results. Backfill with clean fill and reestablish surface features. Exterior caulk at the Pilot School Buildings should be periodically inspected and be repaired to the extent it becomes damaged or deteriorated. This proposed Pilot Preferred Remedy offers a reasoned approach to efficiently manage PCB Caulk, PCB light ballasts and associated fixtures, and contaminated surface soils in Outside Exposure Areas, at the Pilot School Buildings. This proposed Pilot Preferred Remedy is subject to USEPA review and possible modification prior to approval. In addition, the Pilot Preferred Remedy is subject to modification based on the results of ongoing and future Pilot Study activities to be reported in Supplemental Reports to this RIR. TRC ENGINEERS, INC. ix

11 1.0 INTRODUCTION 1.1 Purpose The purpose of this Feasibility Study (FS) is to evaluate the remedial alternatives to address PCB Caulk, PCB light ballasts and fixtures, and PCB-contaminated surface soils, with consideration of the methods and products utilized, affects of remedial alternatives on post-remediation PCB concentrations, reducing human exposure to PCB sources, short-term and long-term effectiveness, cost, labor requirements, length of implementation, potential to disrupt normal school activities, and other relevant factors in primary, transitory and outside exposure areas (defined in Section 1.2.5). This study will help to establish the activities that will inform the development of City-Wide PCB Management Plan, as explained in the Consent Agreement and Final Order (CAFO) Docket Number TSCA between the United States Environmental Protection Agency (USEPA) and the New York City School Construction Authority (SCA) and the City of New York. 1.2 Background In recent years, the USEPA has studied caulking materials and determined that caulk produced between 1950 and 1978 may potentially contain PCBs. Although the manufacture and most uses of PCBs were banned, buildings constructed or renovated from 1950 to 1978, including schools, may contain caulk with PCBs. During this period, the use of PCBs in caulk was legal. Exposure to PCBs in caulk may occur as a result of their release from the caulk into the air, dust, surrounding surfaces and soil, and through direct contact. In September 2009, the USEPA published a series of guidance materials pertaining to the management of PCB Caulk in older buildings. The guidance materials explained the current state of knowledge regarding PCB Caulk and set forth best management practices for addressing PCB Caulk. The USEPA defines "PCB Caulk" as caulk that contains PCBs at concentrations of 50 parts per million (ppm) or greater. Caulk is defined for purposes of this study as any semi-drying or slow drying plastic material used to seal joints or fill crevices around window frames or panes, doors, or other building components; caulk does not include coatings, glazing varnishes or sealants that are or were applied as liquids (U.S. EPA 2010a). On January 19, 2010, the City of New York (the City) and the USEPA reached an agreement regarding the monitoring and remediation of PCB Caulk in public school buildings. As a result of the agreement, the City undertook a Pilot Study to evaluate the possible presence of PCB Caulk and the most effective methods for remediation in five Pilot School Buildings. The study is the first of its kind nationwide in a public school setting. Although the agreement is significant, it is not the first step that the City has taken regarding PCB Caulk. The SCA currently implements a PCB Program that includes protocols to identify and remove PCB Caulk in areas of public schools renovated during capital improvement projects. From June, 2010, through November 2010, the SCA implemented a remedial investigation at three Pilot School Buildings (P.S. 178X/176, P.S. 199M, and P.S. 309K) in accordance with the CAFO and the Remedial Investigation Plan for The New York City School Construction Authority Pilot Study to Address PCB Caulk in New York City School Buildings (RI Plan), prepared by TRC Engineers, Inc. (TRC) and dated July 9, 2010, and approved by the USEPA. From April, 2011, through October, 2011, remedial investigations were implemented in all five Pilot School Buildings, including the additional TRC ENGINEERS, INC

12 Pilot School Buildings P.S. 3R and P.S. 183Q. The scope of the remedial investigations completed so far is summarized as follows: Performed a caulk survey in each of the potential Pilot Study Areas at P.S. 178X/176, P.S. 309K, P.S. 183Q and P.S. 199M; Conducted an initial inspection and collected pre-remedial wipe and air samples in a representative number of areas in each of the five Pilot School Buildings; Conducted soil sampling in unpaved areas immediately surrounding each of the Pilot School Buildings for laboratory analysis as discussed in the Remedial Investigation Plan. Additionally, exterior caulk samples were collected where soil sample results exceeded the comparison criteria; Applied various remedial alternatives for managing PCB Caulk and/or light ballasts in the five Pilot School Buildings; Collected post-remedial air and wipe samples from the same locations as the pre-remedial samples to gauge the effects of the remedial alternatives; Evaluated the effectiveness of current best management practices in each Pilot School Building; Prepared an Interim Remedial Investigation Report presenting and evaluating all data, analytical results of sample analyses, and remedial methods from the first phase of the study performed in 2010; Prepared a Remedial Investigation Report presenting and evaluating all data, analytical results of sample analyses, and remedial methods for the second phase of the study performed in 2011; and, Prepared this appended Feasibility Study utilizing the Pilot Study data and identifying the proposed Pilot Preferred Remedies Relevant Schools From 1950 to 1978, it was legal to manufacture PCBs and use materials containing PCBs in the construction and renovation of buildings. In 1979, PCB manufacturing was banned by Congress and its use phased out due to concerns about potential adverse effects to human health and the environment. The SCA has identified Relevant Schools that were constructed between 1950 and The CAFO focuses on identifying and remediating PCB Caulk that may be present in these schools. A list of the Relevant Schools is presented in Appendix C. TRC ENGINEERS, INC

13 1.2.2 Description of Pilot School Buildings NYCSCA From this list of Relevant Schools, the SCA proposed and the USEPA approved the following five Pilot School Buildings for the Pilot Study. Table 1.1 Summary of Pilot School Buildings NYC School ID School Name Address Current Student Education Levels P.S. 178X/176 Dr. Selman Waksman School/ P.S. 176 (Charter School) 850 Baychester Ave. Bronx, NY Grades K-5/ Grades PK - 12 P.S. 199M Jessie Isador Straus School 270 West 70 th Street Manhattan, NY Grades K-5 P.S. 309K George E. Wibecan Preparatory Academy/Excellence Charter School for Girls 794 Monroe Street Brooklyn, NY Grades PK 5/ Grades K 1 P.S. 3R Margaret Gioiosa School 80 South Goff Avenue Staten Island, NY Grades PK 5 P.S. 183Q K = Kindergarten PK = Pre-Kindergarten Dr. Richard R. Green School 2-45 Beach 79 th Street Queens, NY Grades PK 8 The location of each Pilot School Building is shown on the figures provide in Appendix A. A brief summary of the relevant architectural and mechanical systems at the five Pilot School Buildings follows: P.S. 178X/176 - This school is housed in a three-story brick and concrete building constructed in Five central HVAC units are located on the roof and one HVAC unit is located in the basement of the building. Each unit services a different zone inside the building. The zones are organized as North, South, East, West, and Center. There is central air conditioning (A/C) and perimeter radiant heat. Approximately seven window-mounted A/C units supplement the central HVAC system. Hot water is supplied to the building from an off-site location. The hot water is pumped to the rooftop and basement HVAC units for heating. The windows are double-paned, have a membrane between the panes, and have aluminum casing. Window glazing was recently replaced throughout the school. TRC ENGINEERS, INC

14 P.S. 199M - This school is housed in a three-story brick building constructed in The mechanical systems consist of a classroom and bathroom exhaust system, with perimeter heating units. Make-up air for this system is provided by operable windows. There are 19 rooftop exhaust fans, which were replaced in September of 2008, that service the classrooms and bathrooms. The gymnasium and auditorium utilize forced air for heating and ventilation. The gymnasium and auditorium are serviced by separate blower and exhaust fans located in mechanical rooms on the second and third floors. Outside air enters the gymnasium and auditorium systems through louvers located in the third floor mechanical room. There are window mounted A/C units in the majority of the classrooms. Windows (including frames) were recently replaced in this school. P.S. 309K - This school is housed in a three-story brick building constructed in The mechanical systems consist of a classroom and bathroom exhaust system, with perimeter heating units. Make-up air for this system is provided by operable windows. There are a total of 15 exhaust fans, ten of which are located on the upper roof and five on the lower roof. Basement fans provide forced air heat and ventilation to the auditorium and gymnasium. Outside air enters the gymnasium and auditorium systems through louvers located in the basement mechanical room. There are window mounted A/C units in the majority of the classrooms. Windows (including frames) were recently replaced in this school. P.S. 183Q This school is housed in a three-story brick building built in Four HVAC units are located on the roof; however, these HVAC units are not operable. There are also eleven exhaust fans located on the roof. Approximately ten window-mounted and ten portable units supply air conditioning in certain building spaces. Hot water and steam heat is supplied to the building from two boilers in the basement that operate on No. 6 fuel oil. Wall-mounted steam radiators are utilized throughout the building. The first floor and stairwell windows are hopper windows that fold inward to open. The second and third floor windows consist of two sets of operable double paned sashes for airplane noise reduction in each location. P.S. 3R This school is housed in a one-story brick building with a basement. P.S. 3R was built in 1959, with additions in 1968 and The portion of the school that was constructed in 2005 is not included in the Pilot Study. The mechanical systems consist of a classroom exhaust system vented to the roof. Steam heated radiators are located in each room. Offices contain windowmounted air conditioning units. Three rooftop HVAC units service the newly constructed portion of the school Overview of Remedial Investigations The scope of the remedial investigations, which have been completed within the five Pilot School Buildings, followed the sequential phasing of work as described below: Performed a caulk survey (including sampling, location, quantity, and condition) to inventory suspected PCB Caulk in potential Pilot Study Areas. Conducted pre-remedial air and wipe sampling for laboratory analysis in the Pilot Study Areas. Samples were collected indoors, from primary exposure areas and transitory areas where students are typically located, just prior to performing remedial alternatives. Conducted soil sampling in unpaved areas immediately surrounding each of the Pilot School Buildings for laboratory analysis. TRC ENGINEERS, INC

15 Evaluated various remedial alternatives in each Pilot School Building. The remedial alternatives selected, in consultation with the USEPA, for evaluation during the Pilot Study were: (1) Patch and repair of caulk (i.e., remove loose and deteriorating caulk and replace with new non PCB-containing caulk); (2) Encapsulation of caulk; (3) Removal of all caulk and replacement with new non PCB-containing caulk; (4) Window frame and caulk removal and replacement with new window frames and non PCB-containing caulk; and, (5) Best management practices (i.e., use pre-remedial sampling data from each Pilot School Building to evaluate the effectiveness of current operation and maintenance practices). Remedial alternates (1), (2), and (3) were evaluated in the Pilot School Buildings - P.S. 178X/176, P.S. 309K, and P.S. 199M, respectively. In each of these schools, the remedial alternates were implemented in only limited Pilot Study areas in 2010, and then the remainder of the areas throughout the schools were remediated in Remedial alternative (4) was implemented in 2011 in all areas where windows had not been previously replaced in P.S. 183Q. Remedial alternative (5) was also evaluated in each of the five Pilot School Buildings through the evaluation of the pre-remediation sampling data. In addition, due to findings in the first three Pilot School Buildings studied during 2010, removal of light fixture PCB ballasts was evaluated in one Pilot School Building (P.S. 3R) in 2011 pursuant to the SCA RI Plan modification dated November 23, 2010, which was approved by the USEPA in correspondence dated November 29, Applicable Comparison Criteria This section summarizes the existing comparison criteria for each media that will be incorporated into the evaluation of the Pilot Study results. Bulk Caulk Samples Any bulk caulk samples that exceeded 50 ppm of total PCBs were considered to be PCB Caulk. (Bulk caulk samples will be hereafter referred to as caulk samples.) Air Samples Based upon USEPA s indoor air guidelines for schools and ages of building occupants (U.S. EPA 2009), air sampling results were compared to the following values: Table 1.2 USEPA s Public Health Levels of PCBs in School Indoor Air (ng/m 3 ) Age 3 to <6 yr (Pre Kindergarten and Kindergarten) Age 6 to <12 yr (Elementary School) Age 12 to <15 yr (Middle School) Age 15 to<19 yr (High School) Age 19+ yr (Faculty) TRC ENGINEERS, INC

16 It is important to note that EPA guidance contained in the document entitled "Proper Maintenance, Removal, and Disposal of PCB-Containing Fluorescent Light Ballasts" states, "In order to provide guidance on levels of concern regarding chemicals in the environment, EPA develops reference doses (RfD) and concentrations (RfC). A reference dose is an estimate of a daily oral exposure level that the human population, including sensitive subpopulations that if one were exposed to for a lifetime would not cause appreciable risk to human health. EPA's RfD for the one type of PCB, Aroclor 1254, is 0.02 micrograms per kilogram per day. Based on this RfD and exposure factors such as typical air inhalation rates and the period of time spent at school, EPA has estimated the PCB levels of micrograms per cubic meter of air in schools would not result in harmful effects to human health even if one were exposed over a lifetime. This is a conservative, health protective estimate. EPA's goal is not to have people exposed above this RfD level. Exceeding this level does not mean that adverse effects will necessarily occur. However, as exposure levels become higher, EPA has less confidence that the exposures will not result in adverse effects." Surface Wipe Samples Pre and post-remedial wipe samples were compared to USEPA s High Occupancy wipe sample criteria of 10 µg/100 cm2 (40 CFR 761.3, and ). Soil Samples Soil samples were compared to USEPA s clean backfill standard (40 CFR (4) (v) and 40 CFR (b) (ii)) and the New York State Department of Environmental Conservation (NYSDEC) Technical and Administrative Guidance Memorandum (TAGM) 4046 and 6 NYCRR Part 375 value of 1 ppm for PCBs. Target Laboratory Reporting Limits for each sampling media were below these comparison criteria Nature and Extent of PCB Caulk PCB Caulk has been surveyed and identified in four out of the five Pilot School Buildings. In P.S. 3R, surveying and sampling of interior caulk was not performed as PCB light fixtures were evaluated in place of caulk. At P.S. 178X/176, P.S. 199M and P.S. 309K, all of the spaces within the three buildings were evaluated for PCB Caulk, while in P.S. 183Q only the Pilot Study rooms were evaluated. In the schools evaluated, the condition, concentration, and location of PCB Caulk varied from school-to-school, and even from room-to-room within a particular school. For instance, at P.S. 183Q and P.S. 309K, PCB Caulk was identified in transitory areas but not primary areas, while in P.S. 199M and P.S. 178X/176, PCB Caulk was identified in both primary and transitory areas. In total, 826 individual suspect caulk locations/materials were surveyed in 407 different spaces at P.S. 178X/176, P.S. 199M and P.S. 309K, during the Pilot Study work performed in 2010 and Generally, samples from three or more discrete locations comprising each homogeneous material were composited for laboratory analysis. Of the 826 individual interior caulk locations/materials identified, 176 were found to contain total PCB concentrations greater than 50 ppm. The analytical results for the interior caulk samples obtained from the three schools indicate PCB concentrations ranged from nondetect (less than ppm) to 440,000 ppm. Of those 176 positive individual locations/materials, 78 locations/materials were found to be damaged, deteriorated, and/or loose. Please refer to Section 2.0 of the Interim RI Report and RI Report for additional details regarding the bulk caulk survey and sampling. TRC ENGINEERS, INC

17 At P.S. 183Q, a total of 64 individual suspect caulk locations/materials were surveyed in 12 different locations during the Pilot Study work performed in Of the 64 individual caulk locations/materials identified, 17 were found to contain PCBs greater than 50 ppm, and 13 of those locations/materials were found to be damaged, deteriorated, and/or loose. The analytical results for the interior caulk samples obtained at P.S. 183Q indicate that PCB concentrations ranged from non-detect (less than 1 ppm) to 328,000 ppm. The five schools the Pilot Study has examined represents less than one percent (1%) of the total number of Relevant Schools. From the Pilot Study activities to date, no distinct pattern has emerged that could be used to predict the location, concentration, or condition of PCB Caulk PCB Caulk Fate and Transport Understanding how individuals can be exposed to PCBs is critical in order to evaluate ways to limit exposure. One source of exposure to PCBs is through fine particulates contaminated with PCBs. Once in the air, fine particulate with PCBs may be widely dispersed. Larger sized particulates can also be dispersed, although they tend to settle out of the air fairly rapidly. Contact with such particulate may result in any or all of three possible exposure routes inhalation, ingestion and direct contact. Exposure through inhalation occurs when an individual breathes in air containing respirable sized PCB-laden particulate in the form of dust or deteriorated caulk. Inhalation exposure to PCBs is also possible when PCBs volatilize directly from source materials (e.g., PCB Caulk and ballasts containing PCBs) into indoor air. When an individual comes into direct contact with settled particulates, a portion of the PCBs may absorb through the skin. Ingestion is also possible if particulates are transferred to the mouth. Exposure through direct contact and ingestion are also possible through other means. If an individual directly contacts building materials (e.g., PCB Caulk) or soil contaminated with PCBs, some may be absorbed through the skin. Ingestion is also possible if building materials or soil is ingested directly through hand-mouth transfer. The risks associated with exposure to a given concentration of PCBs are greater in the Primary Exposure Areas, as opposed to Transitory Areas, because individuals spend a longer amount of time in these areas. The RI Report indicates that the dust found in the building does not generally contain PCBs at concentrations above the applicable comparison criteria. Therefore, the risks associated with inhalation, direct contact, and ingestion of PCB-laden dusts are believed to be minimal. Airborne concentrations of PCBs sometimes exceeded the applicable comparison criteria. Therefore, excluding dietary intake, the primary route of exposure within the Pilot School Buildings is believed to be through inhalation of PCBs. The greatest risk from soil is direct contact and ingestion. Because the soil is located outside of the building, any PCBs that volatilize from the soil will tend to dissipate into the atmosphere USEPA Defined Areas to be Evaluated in Each Pilot School Building The CAFO defines three exposure areas requiring study Primary Exposure Areas, Transitory Areas, and Outside Exposure Areas. A brief description of these evaluation areas and the scope of the evaluation are provided below: Primary Exposure Areas - Classrooms, gymnasiums and cafeterias. These areas in the school buildings are where students are typically located for prolonged periods during the school day. Approximately fifteen percent (15%) of the classrooms in each school building were selected for TRC ENGINEERS, INC

18 surveying and sampling. Representative classrooms were selected for sampling and surveying on each floor of the school occupied by students. In addition, the cafeterias and gymnasiums were selected for sampling and surveying, when present. Transitory Areas Interior areas such as stairways, hallways and bathrooms where students may be present, but generally for relatively shorter periods during the school day. One or more transitory areas were surveyed and sampled at each Pilot School Building. Outside Exposure Areas Areas within a ten foot wide strip of any exposed soil immediately adjacent to school buildings. Exposed soil was subjected to sampling and laboratory analysis at three distances from the building (0.5 feet, 3 feet, and 8 feet) at intervals along the building face of approximately twenty feet. 1.3 Scope of Pilot Study The purpose of the Pilot Study is to evaluate the possible presence of PCB Caulk located in primary, transitory and outside exposure areas and evaluate remedial strategies with consideration of the effectiveness of the remedy, logistics, disruption to educational activities, and overall costs. This Feasibility Study will evaluate the remedial alternatives and recommend, a suitable Pilot Preferred Remedy. 1.4 Summary of Findings and Recommendations of the Pilot Study Based on the results of the 2010 and 2011 pilot activities to-date, the following is a summary of the overall findings of the Pilot Study: In all five (5) Pilot School Buildings, despite the significant variability in the quantity and concentration of PCB Caulk concentrations in the study areas, pre- and post-remediation wipe samples were consistently below the USEPA guidance value of 10 µg/100 cm 2. Based on those results, surface exposure through ingestion or dermal contact with PCB-laden dust has not been identified as a concern and current housekeeping/cleaning methods employed by the schools adequately address this issue. Therefore, future pre- and post-remediation low and high contact surface wipe sampling should be discontinued. Airborne PCB concentrations within individual classrooms were typically variable from one sampling event to another. Airborne PCB concentrations also varied between Pilot Study areas during the same sample event. These results are consistent with the temporal and spatial variations associated with the behavior of air in building interiors. Aroclor 1254 was by far the most common contributor to the reported total PCB concentrations in air and wipe samples, with a much smaller portion being attributed to Aroclor No other Aroclors were identified in any of the air or wipe samples collected in the Pilot School Buildings. In all five (5) Pilot School Buildings the remedial methods studied (PCB Caulk encapsulation; PCB Caulk patch and repair; PCB Caulk removal and replacement; PCB Caulk window replacement; and PCB light ballast and light fixture removal and replacement) were effective in controlling airborne PCB concentrations. An additional cleaning of areas following replacement of windows has been recommended. There was not a statistically significant change in airborne PCB concentrations between pre- and post-remedial air sample results at the four (4) Pilot School Buildings in locations where interior PCB Caulk remediation was performed in the summer, Additional air monitoring beyond TRC ENGINEERS, INC

19 the scope of the Pilot Study would be required to determine whether or not there is a significant reduction in airborne PCB concentrations over time that results from the PCB mass removal and control afforded by the remedial measures. Mean airborne PCB concentrations in Transitory Areas appear greater than in Primary Exposure Areas within P.S. 199M, P.S. 3R, and P.S. 183Q for the 2011 Pilot Study, which may be due to the general absence of exhaust ventilation in hallways and stairwells. At P.S. 183Q, an additional, detailed, and fine cleaning of the physical spaces subject to the window removal and replacement work by a qualified environmental contractor resulted in subsequent air sampling results meeting the applicable acceptance criteria. Future window replacement project procedures should be modified to incorporate such a detailed and fine cleaning following the replacement work and prior to re-occupancy. As reported in the IRIR, removal and replacement of the PCB light ballasts and associated fixtures had the most pronounced effect in terms of lowering PCB levels in air in the three Pilot School Buildings in which more than one remedy was implemented (i.e., P.S. 199M, P.S. 178X/176 and P.S. 309K). The primary source of airborne PCB in these schools appears to have been leaking light fixture ballasts, rather than caulk. In PS. 199M, other non-ballast and noncaulk PCB sources appear to be contributing factors as well. In P.S. 3R, concentrations in air were on average lower in Primary Exposure Areas following light fixture removal; however the difference was not statistically significant. The mean airborne PCB concentrations at P.S. 199M were significantly reduced after the light ballast removal and replacement in 2010, and were below the USEPA guidance values during the 2011 winter sampling. However, airborne PCB concentrations were found to be elevated in several spaces prior to and after removal and replacement of all identified PCB Caulk during the summer, This suggests one or more other contributing sources of PCBs are likely present at this school. To continue to reduce PCB air concentrations in P.S. 199M, activated carbon air filtration units are currently operating in all occupied spaces (i.e., classrooms, offices, library, cafeteria, and gymnasium). Carbon filtration has been effective at reducing airborne PCB concentrations, as the mean PCB concentration measured in air within the Primary Exposure Areas decreased significantly after implementing the on-going carbon filtration for approximately one (1) month. After two (2) months of operation, the mean PCB concentration in air was lower than the onemonth results, but the difference was not statistically significant. In the case of both rounds of measurements, the mean PCB concentration was less than the guidance value for elementary-age rooms, with certain individual measurements exceeding guidance values. PCB-containing interior building materials, other than caulk and light ballasts, were identified in P.S. 199M and P.S. 309K. The relative degree to which these other building materials contribute to the airborne PCB concentrations measured in the air is inconclusive, as an evaluation of the data from both schools did not indicate a positive correlation between the quantity of other, specific PCB-containing materials in the various classrooms and the total airborne PCB concentration measured within those same classrooms. However, comparison of representative normalized Relative Source Strength between P.S. 199M and P.S. 309K indicate that the average RSS of major surface area materials at P.S. 199M was more than double the average RSS at P.S. 309K. TRC ENGINEERS, INC

20 Evaluation indicates that the total normalized Relative Source Strength of PCB-containing materials for the select rooms at P.S. 199M ranged from to 1.385, with an average of The total normalized RSS for comparable select classrooms at P.S. 309K ranged from to 0.621, with an average of Although no correlation between the RSS and airborne PCB concentration in either school was identified, the higher normalized RSS in P.S. 199M as compared to P.S 309K, which is similar to P.S. 199M in both construction type and date, as well as ventilation configuration, suggests that the other interior PCB-containing materials may be contributing to the higher mean airborne PCB concentration associated with post-remediation samples at P.S. 199M. Based on a review of the results of soil sampling efforts in 2010 and 2011, varying areas of soil contamination were identified at all five Pilot School Buildings studied. With the exception of one (1) sample location at P.S. 3R, the row-by-row methodology that SCA currently utilizes for soil evaluations outside the Pilot Study would have resulted in the same contaminated soil delineation with less data collection than was required for the remedial investigations. The distance from the building face to which soil contamination extended was typically limited to eight feet. Soil contamination encountered at P.S. 199M, P.S. 178X/176 and P.S. 309K was successfully mitigated through the process of delineation, excavation, and off-site disposal. Soil contamination at P.S. 3R and P.S. 183Q has been isolated pending implementation of soil excavation and disposal. With the exception of P.S. 309K, PCB Caulk was identified on the building exterior of each of the Pilot School Buildings. Survey inspections indicated that the existing PCB Caulk was most often not deteriorated or damaged; therefore, it is unclear as to the extent existing PCB Caulk has contributed to PCBs present in surface soils. PCB Caulk impacted by historical construction projects prior to the use of current PCB Caulk containment and removal procedures is thought to represent a primary source of the PCBs encountered in soil rather than release from existing PCB Caulk. Evaluation of multiple rounds of wide-scale testing data at P.S. 199M suggests a positive relationship between indoor air PCB concentration at P.S. 199M and both indoor and outdoor temperature. In addition, school-wide mean airborne PCB concentrations at P.S. 199M are higher in the warmer summer months, when school is generally not in session and lower in cooler fall and winter months, when school is in session. In addition, on a floor-by-floor basis, mean PCB air concentrations in classrooms were highest on the third floor and lowest on the first floor. The correlation of indoor air PCB concentration and temperature could not be evaluated at other Pilot School Buildings due to the low numbers of temperature data. Based on a simple trend analysis of the data, no correlation was identified between measured air exchange rates and airborne PCB concentrations at P.S. 199M. An evaluation of the ventilation systems at P.S. 199M and P.S. 309K indicated that designed and measured ventilation rates were variable between classrooms. At P.S. 199M, short circuiting of make-up air may be the result of incomplete air mixing within rooms explaining the higher calculated exchange rates relative to the tracer gas-measured air exchange rates. With one or two windows partially opened, measured air exchange rates at P.S. 199M increased by an average of up to 78%. This same phenomenon, although not actually observed, may also occur at P.S. 309K based on room configurations similar to those at P.S. 199M. TRC ENGINEERS, INC

21 On the basis of the work performed and summarized in the Interim Remedial Investigation Report and this Final Remedial Investigation Report (RIR), the following proposed supplemental actions are recommended: (1) Supplemental Actions Related to P.S. 199M - Evaluate indoor air temperature trends by recording and evaluating indoor air temperature on multiple floors over several weeks. For future air sampling events, data log temperature in representative areas throughout each sampling event. - Encapsulate other PCB-containing materials within a representative number of interior spaces and conduct a minimum of two rounds of air sampling and analysis in these same spaces, following encapsulation, to evaluate the impact, if any, on the concentration of PCBs in air. - Perform an airborne pollutant pathway study in representative interior spaces to evaluate the potential migration and distribution of contaminants in air from floor to floor. (2) Supplemental Actions Related to P.S. 178X/176 - Other than implementing the long-term monitoring program, no further post-pilot investigation or remediation actions are recommended at this time. (3) Supplemental Actions Related to P.S. 309K - Due to the relatively low air exhaust rates measured in specific areas at P.S. 309K, engage a heating and ventilation contractor to identify and implement appropriate repairs to the existing ventilation systems. (4) Supplemental Actions Related to P.S. 183Q - Continue to isolate surface soil documented to contain PCB concentrations above 1 ppm as an interim measure pending implementation of soil excavation and disposal. A construction fence associated with a capital improvement project is currently in place. When construction is completed and the construction fence is removed, cover the contaminated soil areas with geotextile fabric and a 3 to 4 top layer of cedar mulch and maintain it. Encapsulate exterior PCB Caulk in areas immediately adjacent to soils to be remediated in accordance with the SCA s commitment to USEPA prior to soil remediation. Remediate soils above 1 ppm by excavation and off-site disposal, and obtain confirmatory post-excavation soil results. Backfill with clean fill and reestablish surface features. - Remove and replace ballasts and light fixtures as part of the on-going light fixture replacement program due to evidence of historic ballast leakage. (5) Supplemental Actions Related to P.S. 3R - Continue to isolate surface soil documented to contain PCB concentrations above 1 ppm as an interim measure pending implementation of soil excavation and disposal. Maintain the existing geotextile fabric and cedar mulch. Encapsulate exterior PCB Caulk in areas immediately adjacent to soils to be remediated in accordance with the SCA s commitment to USEPA prior to soil remediation. Remediate soils above 1 ppm by excavation and off-site TRC ENGINEERS, INC