Regulatory Submittal Part I(R) DOL Comments to Remediation Work Plan Dated: January 17, 2007

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1 Regulatory Submittal Part I(R) DOL Comments to Remediation Work Plan Dated: January 17, 2007 The Department has discussed aspects of the documents with the New York City Department of Environmental Protection (DEP), and DEP concurs with the Department's comments on the submitted documents. Several significant items within the work plan must still be revised to address Departmental concerns. Comments have been numbered to provide cross-reference with the revised work plan document. General Comments GC1 Throughout the work plan submittal, requirements are included for NYS DOL and NYC DEP licensed asbestos handlers". As previously indicated and as per ICR 56, asbestos contractors must be licensed and each individual handler must be appropriately trained and certified. The work plan requirements must be changed globally throughout the work plan document to indicate "asbestos contractor licensing and handler certification shall be consistent with NYS DOL ICR 56 requirements, as well as NYC DEP requirements". This language has been corrected throughout Part I(R) Remediation Operations Work Plan to refer to NYC DEP and NYS DOL certified asbestos handlers. In addition, the following language has been added to Section 6.0: For all asbestos abatement activities on this project, asbestos contractor licensing and handler certification shall be consistent with NYS DOL ICR 56 requirements, as well as NYC DEP requirements. Please note that NYC DEP does not license asbestos contractors. GC2 The concept that floors two through fifteen will comprise one work area, but three floor blocks will be split-up within the work area is problematic at best It is unclear if each three floor block is segregated from the other three floor blocks within the same work area, and do they share the same air source? If all the three floor blocks within the same work area share the same air source and there is no segregation or isolation of these separate portions of the same work area, then abatement, cleaning and clearance must occur throughout all portions of the work area at the same time. For example, the postabatement cleaning in floors 15, 14, and 13 is complete, but ACM is still being removed in the floors below floor 13. As floors 13, 14, & 15 apparently draw make-up air from the remainder of the work area, floors 13, 14, & 15 will likely be re-contaminated by the abatement operations occurring in the remainder of the same work area. All abatement and cleaning operations within each abatement work area must be entirely completed before the project monitor visual inspection commences. The satisfactory visual inspection

2 would then be followed by clearance air sampling of the entire work area. The definition of the work area has been clarified in the Work Plan. The following explanation has been added to Section 6.0: This project has been designed in response to the existing condition of Fiterman Hall. The overall concept of the remediation operations is for the entire interior of the Building to be placed under one comprehensive negative pressure containment for the removal of non-fixed items, building components and asbestos containing materials. In order to accomplish these removals a Clean Zone will be established on the First Floor to provide an area free of contamination for logistical operations in support of remediation activities. Cleaning activities shall follow directly after removals. In order accomplish the postremovals cleaning, the one containment will then be divided into separate, three floor blocks. Each three floor block will be segregated from the neighboring three floor blocks via the installation of critical barriers on all vertical means of air transfer. Cleaning activities will not begin on any floors until all remediation and abatement activities have been fully completed on all levels (interior & exterior) throughout the entire building. Barriers dividing the three floor blocks will remain in place until all adjacent three floor blocks have been cleaned and cleared. Please refer to the below Section 6.21 for the clearance criteria for this project. GC3 The concept that stairwell A & B will be cleaned and cleared simultaneously with the various 3 floor blocks of the upper floors is also problematic. As previously indicated, these portions of the same work area share the same air source and as there is no segregation or isolation of these separate portions of the same work area, cleaning and clearance must occur throughout the entire work area at the same time. See the above response and revision to Section 6.0. Segregation in the form of critical barriers will be installed after removals and prior to commencement of cleaning to prevent air transer between three floor blocks via the A & B stairwells. GC4 The concept that stairwell C will be cleaned and cleared simultaneously with the first floor clean zone is also problematic, as no correlation is included regarding cleaning and clearance of these two portions of the same work area at exactly the same time. As these two portions of the same work area share the same air source and there is no segregation or isolation of these separate portions of the same work area, cleaning and clearance must occur throughout both portions of the work area at the same time. For example, stairwell C is cleaned and cleared but ACM is still being removed in the first floor work area. As Stairwell C apparently draws make-up air from the remainder of the first floor work area, stairwell C will likely be re-contaminated by the abatement operations occurring in the remainder of the same work area. The operations within each abatement work area must be entirely completed before the project monitor visual inspection commences. The satisfactory visual inspection would then be followed by clearance air sampling of the entire work area. Further review of remediation operations has determined that it will be necessary to perform the cleaning and clearance of Stairwell C before commencing the removals,

3 cleaning and clearance in the First Floor Clean Zone in order to accommodate the installation of electrical requirements in Stairwell C. In order to maintain continuity, it will be necessary to change the numbering of the Sub- Sections of Section 6.1 to move the Cleaning of Stairwell C to the beginning. The Cleaning and Clearance of Stairwell C will now be Section All other Sub-Sections of Section 6.1 will follow sequentially behind Section in the order they were written in the original Part I(R) Remediation Operations Work Plan with the exception of new sections added in response to regulator comments. For example a comment regarding sub-section will be responded to in sub-section In this example, and are the same sub-section only now they are numbered differently in response to the revised sequencing. Below is the revised Sub-Section regarding the cleaning and clearance of Stairwell C: Section Cleaning and Clearance of Stairwell C The construction of Stairwell C is of the following materials: Painted Masonry Block Walls Concrete Floor Landings Concrete Deck Steel Stairs Steel Handrails Stand Pipe Light Fixtures Light Bulbs Electrical Conduit Prior to the cleaning and clearance of the First Floor Clean Zone, PAL will commence the cleaning and clearance of Stairwell C. It is necessary to clear the Stairwell C at the beginning of the remediation operations in order to install electric panels for the remediation work on the upper floors of the Building. All electrical power to the Stairwell C will be shutdown prior to the commencement of Cleaning and Clearance activities. A worker and waste decontamination facility will be constructed exterior to the Building on the ground level on the South Side in the Gash Area. NYS DOL and NYC DEP certified asbestos handlers will construct an access tunnel from the decontamination facility into the Building via the Gash Area. The tunnel shall be constructed of hard wood. Prior to constructing the tunnel, the wood panels will be encapsulated in order to render the surfaces cleanable. The tunnel will meet the Stairwell C at the south side of the First Floor landing. The existing painted sheetrock wall into the Stairwell C will be demolished by NYS DOL and NYC DEP certified asbestos handlers in order to create and opening from the south side. The access tunnel will be fully connected to this opening so that there is no air transfer into the tunnel from the First Floor. In order to connect the tunnel to the opening into Stairwell C it will also be necessary to demolish a masonry block wall that is in the path of the tunnel. Prior to commencing the demolition of the painted sheetrock and masonry block walls, the surfaces will be wetted down with amended water to control dust. Please note that it is not possible to fully saturate

4 painted sheetrock or masonry block as these materials do not absorb water. The painted sheetrock and masonry block walls will not be fully saturated with water during demolition. Water will be used to as a means of dust control at all times during the removal the painted sheetrock and masonry block walls to connect the access tunnel to Stairwell C. The painted sheetrock and masonry block walls will be demolished using a combination of manual and mechanical means Debris generated from the painted sheetrock and masonry block walls will be handled and disposed of as asbestos waste. All openings and penetrations into Stairwell C, including the doorway onto each floor will be sealed with two (2) layers of poly. Four (4) air changes with negative pressure differential of point zero two inch (0.02 ) water column will be established within the Stairwell C and the attached access tunnel. Make up air will be drawn from the decontamination unit. Negative air units will be installed in the stairwell on the Fifteenth Floor and vented onto the main roof level via the existing doorway. All light bulbs and fixtures will be detached. Light bulbs and fixtures will be handled and disposed of as universal waste. All interior surfaces of the stairwell and the attached access tunnel will be HEPA vacuumed and wet wiped to remove any residual dust and debris. All used cleaning materials generated during the remediation in the C Stairwell and access tunnel will be double bagged, properly labeled, processed through the waste decontamination facility and disposed of as asbestos waste. Please note that there are no asbestos containing materials present within Stairwell C. Wall, ceiling and floor surfaces will remain in place within the Stairwell C once remediation activities have been completed. After cleaning activities are completed one twelve hour settling/drying period will then be observed in order to allow all surfaces to dry. At the end of this settling period, the Owner s Environmental Consultant and PAL superintendent will perform a visual inspection of the C Stairwell work area. After the area has passed visual inspection by the Owner s Environmental Consultant, the regulators will be contacted to perform a regulatory visual inspection. Twenty-four (24) hour notice will be provided prior to the regulatory visual inspection. After the Stairwell C work area has passed regulatory visual inspection, aggressive clearance air sampling will be performed by the Owner s Environmental Consultant. Sampling will be performed as follows: 5 TEM air samples (1 sample for every 3 floors) and 5 Metals air samples (1 sample for every 3 floors) will be run for the entire stairwell. Sample locations will be evenly distributed vertically through the stairwell. Clearance testing for all work areas will be consistent with the work area Clearance Criteria noted in section Once successful clearance is achieved the modified full containment in the C Stairwell will remain in place in order to prevent recontamination from yet-to-be-cleaned areas. After decontaminated floors have been cleared the entrances into Stairwell C will be unsealed to provide clean access to clean areas. After the Stairwell C has been cleared GFCI equipped electrical panels will be installed on each floor level within the stairwell by licensed electricians. Power will be run from the electrical closets that abut the south side of the Stairwell C wall on Floors 2 through 15. Specific Comments REGULATORY SUBMITTAL PART I - WORK PLAN 3.1 ASBESTOS SURVEY SC1) This section refers the reader to the Environmental Characterization Report for results of the survey. A summary of the survey results listing the ACMs found and their

5 locations shall also be included within this section. A summary survey of results has been included with Part I(R) Remediation Operations Work Plan as Attachment VIII. 3.2 NYS DOL NOTIFICATION & 3.3 NYS DOL VARIANCE APPLICATIONS SC2) These sections indicate that a variance petition is included within Work Plan Attachment 11 for abatement work that is not in compliance with Industrial Code Rule 56 (ICR 56). However the variance petition is not apparent within the work plan. As previously indicated, if procedures must be specified that aren't consistent with (ICR 56) requirements, a site-specific variance decision must be obtained by the project designer as an agent for the owner, and the procedures and conditions contained within the sitespecific variance decision must then be incorporated into the work plan specified asbestos project procedures, prior to obtaining the necessary regulatory agency work plan approvals. o The site-specific variance petition, has yet to be submitted to the Department for an official decision. The variance petition must be submitted using the standard DOSH-751 form along with appropriate processing fee, prior to the Department issuing an official decision on the petition. Conditions/requirements may be added by the Department within the variance decision for adequate health and safety protection of all parties on the project, as well as thegeneral public. The variance petition must be submitted as soon as possible, to alleviate any potential project scheduling issues. As with Part I(S) SEO Work Plan, it was first necessary to elicit information as to whether the Remediation Operation Work Plan was generally acceptable to DOL prior to making the formal variance application. The formal variance application will be submitted, on the required form, with the required fee once the DOL comments and concerns have been addressed. 4.1 ELECTRIC SC3) This section indicates that GFCI equipped electric panels will be installed on each floor and attached directly to the electrical closet on that level. However, nothing is included regarding adequate protection of the live electric within the electrical closet that is not GFCI protected. At what point during work area preparation will the GFCI panels be installed? Also, how and when will the live electric within the electrical closet be protected and segregated from the work area on that specic floor. The following statement has been added to Section 4.1: Electric panels will be installed at each level required in Stairwell C after cleaning and clearance is completed in the stairwell. The panels will be attached to the electrical closets through the adjoining wall in Stairwell C. The entrances of the electrical closets shall be sealed off prior to the commencement of the remediation operation segregating the live electric from the work areas.

6 4.2 PLUMBING SC4) This section includes information for the water supply to be utilized during the asbestos project but nothing is included regarding drainage systems to be utilized for the asbestos project, filtering systems for the wastewater, discharge points or necessary discharge permits. All pertinent information regarding wastewater collection, temporary storage and disposal must be provided The following statement has been added to Section 4.2: At the beginning of work on the Remediation Operations, a characterization of waste water will be performed to determine proper disposal methodology. Waste water will be filtered to five (5) microns and containerized in a drum for testing. Should the characterziation determine that there are no contaminants present in the waste water it will be discharged into the existing sanitary sewage system in the Building. The procedure for the disposal of water for the entire Remediation Operations will then be to filter down to five (5) microns and discharge to the existing sanitary sewage system. Should characterization detect the presence of contaminants, the waste water generated during the Remediation Operations will be containerized and disposed as required by the characterization analysis. 4.5 ELEVATOR SERVICE SC5) This section does not include any information regarding venting of the elevator shafts or negative pressure engineering controls to filter and control the vented air. A summary of the proposed engineering controls for operation of the elevators must be included within this section. Specific details, procedures and requirements may be addressed within a more detailed section of the work plan. Please note that all asbestos project work plan procedures regarding elevator operation shall correspond with all conditions and procedures within existing site-specific variance decisions, decision amendments and decision reopenings for the project The following statement from Section 6.5 has been cut and moved to Section 4.5 In the Elevator Machine Rooms throughout the Building there are vents that handle air pushed up shafts during car operation. These vents cannot be sealed since the usage of the elevators is required to perform the remediation operations. Negative air filtration units are currently operating in these Elevator Machine Rooms maintaining negative pressure in order to prevent contaminated air from migrating out of the elevator shafts. Negative pressure will be maintained in the Elevator Machine Rooms during remediation operations. 5.4 VISUAL INSPECTION SC6) This section appears to include general information regarding completion of a work area visual inspection for completeness of abatement and cleanings. However, nothing is included regarding the actual personnel that are required to complete the inspection, and no reference is included to specific requirements for visual inspections as required by

7 ICR 56. The following statement has been added to Section 5.4: Visual inspection will be performed by the contractor supervisor and the Owner s Environmental Consultant. Visual inspection will be performed in accordance with ICR 56. SC7) Specific criteria must be defined and appropriate parties identified with responsibility for conducting visual inspections (e.g. ASTM E1368 requirements completed by owner's project monitor after satisfactory visual inspection by abatement contractor supervisor, etc.). Appropriate sections of ICR 56 must be referenced as necessary. In addition, provisions must also be included within the work plan to allow for regulatory agency visual inspections prior to commencement of clearance air sampling. The following language has been added to Section 5.4: After removals and cleanings are complete in a work area, the Owner s Environmental Consultant and Contractor representative will perform a visual inspection of the area. The Owner s Environmental Consultant representative performing a visual inspection shall be an NYS DOL and NYC DEP certified project monitor. OEC visual inspection will be conducted as per the provisions of ASTM Standard 1368 Standard Practice for Visual Inspection of Asbestos Abatement Projects in accordance with ICR 56 Section 56.9(d)(1). Once a work area has passed the OEC visual inspection, an OEC representative will contact the regulators to schedule a regulatory visual inspection of the work area. Twenty-four hour notice shall be provided to the regulators prior to the date of inspection. After the area has passed regulatory visual inspection, aggressive clearance air sampling will be performed by the Owner s Environmental Consultant. Please refer to the below Section 6.21 for clearance criteria. 6.0 REMEDIATION OPERATIONS SC8) This section indicates that the Office of the City Medical Examiner will perform a complete inspection of the building & site prior to commencement of remediation operations. Please provide a summary of inspection procedures and also indicate if any potential disturbance to ACM or WTC dust1residue will occur during these search operations. If a disturbance may potentially occur, indicate what engineering controls will be in place during the search to prevent any potential airborne release of asbestos fibers outside the building envelope. Following the submission of Part I(R) Remediation Operations Work Plan to the Regulators, the Office of the City Medical Examiner (OCME) performed an inspection of the Building and determined that search operations would not be required within the interior of the Building. This inspection was visual and did not distrub any ACM or dust

8 residue. The Office of the Chief Medical Examiner (OCME) completed a walk-through at Fiterman Hall on December 12, 2006 and issued a report dated December 20, Their inspection determined that only the exterior roof areas need to be searched for human remains. The interiors were free from any debris. Accordingly, after remediation work begins at the site, representatives of OCME will conduct this search. The following procedure has been added to Section 6.13: OCME has indicated that it will be necessary to perform search operations on the various roof levels of the Building. OCME will be supported by NYS DOL and NYC DEP certified asbestos handlers during their operations. The surface of the roof levels at the Building have been previously cleaned by others during WTC recovery operations. The contractor shall re-clean the ballast and surface of the membrane in conjunction with the Office of the City Medical Examiner investigation as outlined below. After cleaning and OCME inspection, the ballast material will be loaded into bags. Full bags of ballast will be left in place on the roof levels in order to provide weight to hold the membrane in place. Bags of ballast will be removed during the deconstruction operations and disposed of as conventional waste. The following procedure will be used during OCME inspection of roof levels: A screen filtration system consisting of a heavy duty rectangular screen laid flat over four cinder blocks leaving space of approximately one foot to the surface of the roof will be established. A decontamination unit will be installed on each roof level where OCME inspection will take place. NYS DOL and NYC DEP certified asbestos handlers will move sections of stone ballasts and accompanying fines onto the filtration screen. OCME personnel will inspect ballast and fines on the screen as well as the surface of roof membrane for the presence of human remains. Once directed by OCME personnel, NYS DOL and NYC DEP certified asbestos handlers will clean the ballast and fines on the screen with water. The surface of roof membrane where ballast and fines were removed from will also be cleaned by HEPA vacuuming and wet wiping. Run off water will be collected in basins set up below the screen. Collected water will be absorbed on a regular basis utilizing mops and rags or otherwise containerized in drums. Drummed water will be tested for NYC Sewer discharge parameters and eventual filtration to the NYC Sewer if analytical results allow. All used water collection materials will be double bagged, properly labeled, processed through the decontamination facility and removed from each roof level via the exterior pipe scaffolding system for disposal as asbestos waste or in accordance with any waste characterization results. Once cleaned ballast and fines will be moved from the screen and placed into bags and put back onto the roof surface.

9 After the cleaning of stone ballast and roof surfaces in conjuction with OCME, the Owner s Environmental Consultant will perform a visual inspection of the roof levels to verify the cleaning has been fully completed. This procedure will be repeated until OCME has completed their inspections on the roof levels. 6.1 ESTABLISHMENT OF CLEAN ZONE SC9) This section indicates that the personal decontamination facility utilized for remediation of the clean zone will be the existing decontamination facility at the northwest entrance of the building. However, the Decontamination of the Clean Zone and Upper Access Level Access Plan Drawing provided in Attachment V of the work plan does not accurately reflect this information. The provided plan drawing indicates no access to the building interior from the existing northwest entrance decontamination facility, and also indicates that a personal decontamination facility will be constructed at the West Broadway side of the building for access to the intended clean zone for decontamination. This plan drawing and the pertinent work plan text must be revised to appropriately reflect the intended location of the personal decontamination facility for this work. The logistics plan (Remediation Part I(R) Work Plan - Attachment V) entitled Decontamination of the Clean Zone and Upper Level Access shows a decontamination facility in the northwest corner of the First Floor. This decontamination unit will be used for the decontamination and abatement work in the First Clean Zone. SC 10) This section indicates that "asbestos handlers will clean the interior surfaces of all windows in the first floor clean zone work area by HEPA vacuuming and wet-wiping. Following cleaning, all windows, openings and building penetrations will be sealed with two layers of six-mil poly..." However, it is unclear how operable window hidden surfaces that may still contain WTC dust will be cleaned prior to sealing of the windows as critical barriers. The procedures must be revised accordingly. Cleaning of operable window mechanisms has been submitted as Amendment 7 to Part I(S) SEO Work Plan. The procedure will be performed as follows: Asbestos air sampling will be conducted by the Owner s Environmental Consultant outside the building on the scaffold on the perimeter of the active window cleaning work areas established by the Contractor. The number and location of samples will be determined by the Site Hygienist based on the number, location and configuration of the work area(s). The cleaning of windows and operable mechanisms will be performed by NYS DOL and NYC DEP certified asbestos handlers utilizing proper PPE. PPE for the cleaning of operable window mechanisms shall be: disposable coverall suits with hoods, half-face APR equipped with P100 filter cartridges,

10 nitrile gloves, safety goggles, work boots, rubber boot covers, hard hats and hearing protection (only if noise levels exceed OSHA decibel limits). The existing decontamination unit at the northwest entrance to the 1st Floor will be used for interior window related decontamination activities. The existing remote decontamination unit on the Greenwich Street side of the Building will be used for exterior window related decontamination activities. The affected windows are awning type windows that have an operable middle section which opens outward. The cleaning of operable window mechanisms shall occur on no more than three (3) floors at the same time. This operation is being limited in number to a manageable amount so that windows that are not scheduled for cleaning are not left unlatched or unsecured. The cleaning of windows and operable mechanisms will coincide with the installation of scaffolding on the exterior of the Building in order to provide a working platform from which to access the operable mechanisms. A separation of twenty-five feet (25 ) between asbestos and non-asbestos trades will be observed during the cleaning of the operable window mechanisms. Workers will enter the building to clean the interior surface of the operable section of each window will be cleaned via HEPA vacuuming and wet wiping prior to the installation of critical barriers. The installation of critical barriers will proceed from the affected floor upwards. Cleaning materials will be disposed of as asbestos wastes at a minimum or in accordance with any waste characterization testing deemed necessary by the Owner s Environmental Consultant. After interior cleaning is completed, windows will be left closed but unlatched to allow for the cleaning of the operable mechanism from the Building exterior. Critical barriers will be installed over the operable section of each window in order to prevent air transfer between the interior of the Building and the outside environment during cleaning activities. The inoperable fixed sections of the windows will not be sealed because there is no air transfer with the outside environment through these sections. The installation of critical barriers over all operable sections of windows on a given floor will be completed prior to the commencement of operable window mechanism cleaning activities on that floor. The installation of critical barriers will proceed from the lowest affected floor upwards. Once the critical barriers have been installed on a floor, NYS DOL and NYC DEP certified asbestos handlers will proceed to that level on the exterior scaffold platform. Workers, equipped with abatement work area PPE, will open the unlatched operable section of window and clean the interior surface and operable mechanism of each window by HEPA vacuuming and wet wiping. Cleaning will be performed from the lowest affected floor upwards utilizing the exterior scaffolding as a working platform. All cleaning materials generated during the cleaning of windows and operable mechanisms will be containerized, decontaminated and stored in the existing SEO waste storage facility for disposal as asbestos waste at a minimum, or in accordance with any waste characterization testing deemed necessary by the Owner s Environmental Consultant.

11 After the completion of window mechanism cleaning activities, the Owner s Environmental Consultant will perform visual inspections of the cleaned surfaces. After the windows have passed visual inspection they will be secured in place by self tapping screws installed into the frames by NYS DOL and NYC DEP certified asbestos handlers. SC 11) This section indicates that "airlocks will be installed at the entrances to all stairwells with the exception of stairwell C". Please explain the purpose and function of these airlocks, as these stairwells will not be included as part of the initial clean zone work area, and make up air to the intended "clean zone" will be entering the work area through these airlocks to contaminated stairwells. This section has been revised to state the following: All stairwells, with the exception of the cleaned and cleared Stairwell C, will be sealed off from the Clean Zone with critical barriers. Stairwell C will provide a clean area to install electrical panels and provide clean access to the upper floors. SC 12) This section indicates that 4 air changes per hour will be maintained in the clean zone and stairwell C work area, but "it will not be possible to maintain negative pressure of point zero two inch water column". If -0.02" of water column pressure differential, as evidenced by manometer, is not maintained within the work area, then adequate negative air ventilation has not been provided for the work area. Section 6.1 has been revised to state the following: Negative pressure ventilation equipment (micro traps) will be installed to establish negative pressure within the First Floor work area and the C Stairwell. Air volume shall be changed four times per hour in the First Floor Clean Zone work area and negative air pressure differential of point zero two inch (0.02 ) water column maintained. Evidence of negative air pressure shall be demonstrated by a manometer in the First Floor Clean Zone work area. SC13) Also calculations are provided for determining the minimum number of negative air units required. The calculations provided within this section do not appear to include a safety factor for reduced CFM capacity for each unit. An appropriate safety factor should always be utilized when calculating minimum number of negative air machines, as the manufacturer provided CFM capacity is provided for a new machine, with a new HEPA filter and no exhaust tube. Obviously, restrictions are introduced when the exhaust tube is attached to the machine and the HEPA filter is no longer new. All flow restrictions must be appropriately accounted for in negative air flow calculations. Microtrap calculations have been revised to account for reduced CFM and submitted to DOL for review in the revised Part I(R) - Remediation Operations Work Plan. Refer to Sections 6.1 and 6.5 for microtrap calculations. SC14) In addition, nothing is included within this section for any necessary selective

12 demolition required to complete the installation of the critical barriers and to completely isolate the work area from the exterior environment as well as the remainder of the building (e.g. openings/penetrations at columns, shafts, curtain walls, etc.). Obviously any selective demolition necessary must be completed at the conclusion of work area preparation (including establishment of negative air ventilation and installation of the remainder of the critical barriers). The following statement has been added to Section 6.1: It is not anticipated that any selective demolition will be required to complete the installation of critical barriers to completely the isolate the work area from the exterior environment. If selective demolition is determined to be necessary to complete the installation of critical barriers, it will be performed at the conclusion of work area preparation, including the establishment of negative pressure and the installation of the remainder of the critical barriers in that area NON-FIXED ITEMS (Now 6.1.2) SC15) This section does not include the requirement that itemsrcomponents with hidden or inaccessible void spaces, which can not be completely cleaned/decontaminated, must be disposed of as asbestos waste at a minimum. The following description is included in Section regarding the disposal of items that cannot be cleaned. If attempts to clean the above listed non-fixed items are not successful or possible due to compromised condition, they will be wrapped in two layers of poly, properly labeled, processed through the waste decontamination facility and disposed of as asbestos waste. Any non-fixed items that are porous or otherwise incapable of being cleaned will be wrapped in two layers of poly, properly labeled, processed through the waste decontamination facility and disposed of as asbestos waste. Section Please note that the removal of non-fixed items does not include the removal of components within hidden or inaccessible void spaces. Non-fixed items refers to movable objects that are present throughout the building and not attached to any surfaces (i.e. furniture, construction materials from the incomplete renovation work).the removal of fixed or attached components such as duct work or piping is detailed in Section INTERIOR WALLS AND CEILING SYSTEMS (Now 6.1.4) SC16) This section indicates that sheetrock, ceiling systems and other materials that do not readily absorb water will be thoroughly saturated during removal. There may be a misinterpretation of Section by this comment. Below is an excerpt from Section regarding wetting of non-hygroscopic materials:

13 Please note that it is not possible to fully saturate painted sheetrock, ceiling systems or other materials that do not absorb water. These items will not be fully saturated with water during removal. Water will be used to as a means of dust control at all times during the removal of interior sheetrock walls, ceiling systems or other materials do not absorb water. Section SC17) This section must be revised to indicate that materials to be removed shall be adequately wetted with amended water. Sufficient time shall be allowed for penetration to occur prior to abatement activities. All friable asbestos materials shall be thoroughly saturated. All non-hygroscopic (material that resists wetting) material shall be thoroughly wetted, prior to and during abatement. The following statement has been added to Section 6.1.4: Water will be applied continually as a means of dust control during the removal of interior sheetrock walls, ceiling systems or other non-asbestos materials that do not absorb water. Please note that work detailed in Section does not involve the removal of any asbestos material. The removal of asbestos material is addressed in Section SC18) This section does not include any prohibition of ACM disturbance during removal of non-acm systems. This requirement must be included within this section as ACM removals will commence following completion of the non-acm removals. Section has been revised to include the following statement: To the extent possible, workers will not disturb asbestos containing materials during the removal of non-acm systems. If it becomes necessary to remove ACM to access non- ACM systems, the ACM removal will be performed as outlined in Section prior to removal of the affected non-acm systems ASBESTOS-CONTAINING MATERIALS (Now 6.1.5) SC19) This section indicates that friable ACM pipe insulation and non-friable floor tiles will be removed simultaneously within the contained work area. However, ACM removal must be sequential as indicated within ICR All friable ACM must be removed first followed by an intermediate cleaning, and then all non-friable ACM shall be removed. This section must be revised to correspond with ICR 56 requirements. Section has been revised to include the following statement: In any areas where both friable and non-friable ACM are present within the same, immediate working area, all of the friable ACM in that area will be removed first. Following the removal of the friable ACM, the immediate working area will be cleaned by HEPA vacuuming and wet wiping. After this intermediate cleaning, the non-friable ACM in that immediate working area will be removed.

14 SC20) In addition, requirements consistent with ICR (o) must be included. This section of ICR 56 indicates that, power tools used to drill, cut, or otherwise disturb asbestos material in regulated abatement work areas, shall be manufacturer equipped with HEPA-filtered local exhaust ventilation'. Section has been revised to include the following statement: Any power tools used to disturb asbestos containing material will be equipped with HEPA filter exhaust ventilation CLEANING AND CLEARANCE OF THE FIRST FLOOR CLEAN ZONE SC21) This section must be revised to include the requirement that encapsulation of removal surfaces is prohibited until after satisfactory clearance air sample results have been obtained. The Cleaning and Clearance of Stairwell C has been revised. Please refer to the above response to the General Comment regarding Stairwell C to review this revision. SC22) In addition, please include a description of all anticipated remaining surfaces within the first floor clean zone following abatement, cleaning and clearance (e.g. masonry and steel construction with no interstitial spaces remaining at ceilings or walls... all exposed surfaces remaining at completion of cleaning and clearance are non-porous painted concrete or steel). The following list of surfaces to remain after the completion of clearance of the First Floor Clean Zone has been added at the end of Section 6.1: Steel Structurals Metal Hangers and Attachment Mechanisms Masonry Walls Concrete Deck Concrete Floor Slab Glass Window Wall Steel & Masonry Columns Cables Please note that all masonry surfaces that will remain will have been cleaned by HEPA vacuuming and wet wiping during remediation operations. These surfaces will have passed visual inspection and final air clearance and been encapsulated CLEANING AND CLEARANCE OF STAIRWELL C SC23) This section indicates that stairwell C will be cleaned and cleared simultaneously with the first floor clean zone, but no correlation is included regarding cleaning and clearance of these two portions of the same work area at exactly the same time. As these two portions of the same work area share the same air source and there is no segregation or isolation of these separate portions of the same work area, cleaning and clearance must

15 occur throughout both portions of the work area at the same time. As previously indicated, this approach is problematic at best The operations within each abatement work area must be entirely completed before the project monitor visual inspection commences. The satisfactory visual inspection would then be followed by clearance air sampling of the entire work area. The Cleaning and Clearance of Stairwell C has been revised. Please refer to the above response to the General Comment regarding Stairwell C to review this revision. SC24) In addition, as no wall, ceiling or other system removals are planned for Stairwell C, please include a description of Stairwell C construction, as well as a description of all remaining surfaces within the stairwell following cleaning and clearance (e.g. masonry and steel construction with no interstitial spaces at ceilings or walls... all exposed surfaces remaining at completion of cleaning and clearance are non-porous painted concrete or steel). The following list of the stairwell construction materials/surfaces to remain after the completion of clearance of Stairwell C has been added at the end of Section 6.1.7: Steel Structurals Metal Hangers and Attachment Mechanisms Steel Stairs Steel Handrails Stand Pipe Concrete Deck Concrete Slab Masonry Walls Please note that all masonry surfaces that will remain will have been cleaned by HEPA vacuuming and wet wiping during remediation operations. These surfaces will have passed visual inspection and final air clearance and been encapsulated. SC25) This section also indicates that Stairwell C barriers will be broken down following satisfactory clearance and then all accesses to the stairwell will be sealed from the upper floors. This requirement must be modified to prevent any access to stairwell C from upper floor contaminated areas. The critical barriers sealing upper floor access to Stairwell C should remain in place following completion of Stairwell C satisfactory clearance air sampling. This procedure should be included within the sitespecific variance petition. The Cleaning and Clearance of Stairwell C has been revised. Please refer to the above response to the General Comment regarding Stairwell C to review this revision FIRST FLOOR CLEAN ZONE AND C STAIRWELL CLEARANCE CRITERIA SC26) This section indicates that 5 TEM samples will be collected per floor of work area.

16 How does this requirement relate to clearance of Stairwell C? Does this mean that approximately 75 TEM samples will be collected from Stairwell C during clearance air sampling? Minimum clearance air sampling requirements must be further clarified. The follwowing clearance testing procedure is included in the revised Stairwell C cleaning and clearance procedure: After the Stairwell C work area has passed regulatory visual inspection, aggressive clearance air sampling will be performed by the Owner s Environmental Consultant. Sampling will be performed as follows: 5 TEM air samples (1 sample for every 3 floors) and 5 Metals air samples (1 sample for every 3 floors) will be run for the entire stairwell. Sample locations will be evenly distributed vertically through the stairwell. Clearance testing for all work areas will be consistent with the work area Clearance Criteria noted in section SC27) In addition, please include a description of all anticipated remaining surfaces within the first floor clean zone following abatement, cleaning and clearance (e.g. masonry and steel construction with no interstitial spaces remaining at ceilings or walls... all exposed surfaces remaining at completion of cleaning and clearance are non-porous painted concrete or steel). The following list of surfaces to remain after the completion of clearance of the First Floor Clean Zone has been added at the end of Section 6.1: Steel Structurals Metal Hangers and Attachment Mechanisms Masonry Walls Concrete Deck Concrete Floor Slab Glass Window Wall Steel & Masonry Columns Cables Please note that all masonry surfaces that will remain will have been cleaned by HEPA vacuuming and wet wiping during remediation operations. These surfaces will have passed visual inspection and final air clearance and been encapsulated. 6.2 UPPER LEVEL ACCESS SC28) This section indicates that the personal decontamination facility will be constructed at the West Broadway East side Lobby south entrance. However, the clean zone configuration plan drawing indicates that the personal decontamination facility shall be constructed within the building at the south interior entrance to the east Side Lobby. The plan drawing and work plan text must be revised accordingly. The logistics plan (Attachment V) entitled Decontamination of the Clean Zone and Upper Level Access shows that the location of the personal decontamination unit is

17 outside the Building attached to the East side Lobby south entrance as indicated in Section 6.2. The personal decontamination unit will not move inside of the Building until the Clean Zone has been cleared. It will be necessary to gain access to the upper levels during the work to decontaminate the Clean Zone, so it is necessary to have this decon exterior to the Building until the Clean Zone is established. SC29) In addition, this section indicates that upper floor access and abatement of the first floor clean zone will occur simultaneously. This simultaneous access would be impossible if the personal decontamination facility is actually located within the first floor work area. These inconsistencies must be appropriately addressed. Decontamination facilities are located outside of the Building during simultaneous work procedures on the Upper Floors. Refer to logistics plan (Attachment V, page 55 Decontamination of the Clean Zone and Upper Level Access). 6.3 SHREDDER INSTALLATION SC30) This section indicates that a section of north side curtain wall will be removed to allow installation of the shredder. However, nothing is mentioned regarding any impact to remaining exterior ACMs. Please clarify this section accordingly. The following statement has been added to Section 6.3: There are no exterior ACMs present at the north side curtain wall. This area of the Building is double height with no kneewall present. SC31) In addition, a minimum of eight air changes per hour must be maintained within the shredder area during shredder operations. A manometer shall be installed within this area to continuously document pressure differential readings within the shredder processing area. Please note that the Remediation Operations will be performed in one containment. The shredder will be inside of this containment. The following statement has been added to Section 6.3: The contractor will install negative pressure ventilation equipment, as demonstrated by calculations, to provide eight (8) air volume changes per hour in the Shredder Zone. Please note that the shredder zone is part of the one containment work area where air volume will be changed four (4) times per hour in accordance with ICR 56. A manometer shall be installed in the shredder zone to document pressure differential in this area. SC32) All processing of waste through the shredder must be completed using wet methods, and no visible emissions are allowed during the processing procedure. Waste to be processed must be adequately wet during processing operations and after processing

18 when loaded into waste containers. Please note that only non-acm will be processed through the shredder. As stated in Section 6.3 of Part I(R) Remediation Operations Work Plan, the shredder will be equipped with a misting systems. The shredder will be equipped with a water misting system to control dust while materials are processed through the hopper. Section 6.3, page 20 This language has been revised for clarification to state the following: The shredder will be equipped with a wet misting system for dust control. The misting system consists of a plastic attachment for a water hose. The attachment spreads water from the hose in an even and repetitive manner across the shredder loading hopper. The misting system shall be running continuously at all times while the shredder is being operated. The shredder area will be placed under negative pressure as part of the containment of the upper levels. SC33) The list of shreddable materials includes various metal items, wood and porcelain items. Further details must be provided regarding limitations of the shredder. What type of materials can not be processed by the shredder (other than ACM)? Can any thickness metal be processed? Also, are there any engineering controls at the shredder itself, such as localized HEPA-filtered negative air ventilation? It is not anticipated that building materials scheduled for removal during the Remediation Operations which cannot be processed through the shredder will be encountered. The following statement has been added to Section 6.3: Should any non-porous, non-asbestos materials be encountered that cannot be processed through the shredder, they will be cleaned for disposal as conventional waste after inspection by the Owner s Environmental Consultant or otherwise disposed of as asbestos waste or in accordance with any waste characterization results. Should any porous, non-asbestos materials be encountered that cannot be processed through the shredder, they will be disposed of as asbestos waste or in accordance with any waste characterization results. See the above comment SC32 regarding the shredder misting system. There will be enough negative pressure ventilation equipment to provide eight (8) air volume changes per hour in the shredder zone. No other engineering controls will be provided at the shredder itself. 6.4 ESTABLISHMENT OF SECONDARY LOADING DOCK SC34) This section indicates that a section of west side curtain wall will be removed to allow for loading dock conversion. However, nothing is mentioned regarding any impact to remaining exterior ACMs. Please clarify this section accordingly.