BLASER VAPOR INTRUSION INSPECTION, MONITORING, AND MAINTENANCE WORK PLAN SEATTLE, WASHINGTON

Transcription

1 BLASER VAPOR INTRUSION INSPECTION, MONITORING, AND MAINTENANCE WORK PLAN SEATTLE, WASHINGTON August 7, 2008

2 BLASER VAPOR INTRUSION INSPECTION, MONITORING, AND MAINTENANCE WORK PLAN SEATTLE, WASHINGTON Prepared for: Blaser Die Casting 5700 Third Avenue South PO Box Seattle WA And Kirkpatrick and Lockhart Preston Gates Ellis LLP 925 Fourth Avenue, Suite 2900 Seattle, WA Prepared by: Pacific Groundwater Group 2377 Eastlake Avenue East, Suite 200 Seattle, Washington August 7, 2008 JK0504 VI IM&M workplan

3 TABLE OF CONTENTS 1.0 INTRODUCTION BACKGROUND LOCATIONS MITIGATION SYSTEMS INSPECTION AND MONITORING PREVIOUS INSPECTION AND MONITORING Pressure Field Extension Tests Indoor Air Quality Monitoring Tenant Manometer Checks Annual Inspections PROPOSED INSPECTION AND MONITORING Pressure Field Extension Tests Indoor Air Quality Monitoring Tenant Manometer Checks Annual Inspections RE-EVALUATION/ENHANCEMENT OF MITIGATION SYSTEMS SYSTEM MAINTENANCE SYSTEM SHUTDOWN VI IM&M REPORTING REFERENCES...6 BLASER VI IM&M WORK PLAN AUGUST 7, 2008 iii

4 TABLES Table 1: Table 2: Proposed Inspection and Monitoring Schedule Previous Indoor Air Quality, Manometer, and Pressure Field Extension Tests FIGURES Figure 1: Figure 2: Vicinity Map, Blaser Die Casting Blaser Lead Business Site Map APPENDICES Appendix A: As-built Diagrams of VI Mitigation Systems Appendix B: Annual Inspection Forms Appendix C: Manometer Check Reminder BLASER VI IM&M WORK PLAN AUGUST 7, 2008 iv

5 SIGNATURE This report, and Pacific Groundwater Group s work contributing to this report, were reviewed by the undersigned and approved for release. Janet Knox Principal Environmental Geochemist Washington State Geologist No. 413 BLASER VI IM&M WORK PLAN AUGUST 7, 2008 v

6 1.0 INTRODUCTION This Blaser Vapor Intrusion (VI) Inspection, Monitoring, and Maintenance (IM&M) Work Plan (Work Plan) was developed by Pacific Groundwater Group (PGG) on behalf of Blaser Die Casting (Blaser) in the Georgetown neighborhood of Seattle, Washington (Figure 1). This Work Plan provides detailed IM&M requirements for VI mitigation systems currently operating in buildings for which Blaser is the Lead Business for Inhalation Pathway Interim Measure (IPIM) activities. The building locations are shown in Figure 2. Work Plan development is in accordance with the requirements of Enforcement Order No. DE5479 between the Washington State Department of Ecology (Ecology) and Blaser, dated January 31, BACKGROUND Corrective action under Resource Conservation and Recovery Act (RCRA) Facility Operation Permits and Washington State Model Toxics Control Act (MTCA) Regulations (WAC ) required Philips Services Corporation (PSC) to assess and mitigate VI of volatile organic compounds (VOCs) associated with releases at the former waste management facility at 734 South Lucile Street. PSC developed and began implementing an Inhalation Pathway Interim Measure (IPIM) Program (PSC, 2002a). The IPIM approach integrates the analytical results of groundwater and indoor air samples to assess the need for further investigation or mitigation by way of an interim measure. As part of the IPIM Program, PSC conducted groundwater investigations in the Georgetown neighborhood west of 4th Avenue South (W4 Investigation Area). Groundwater samples collected adjacent to Blaser by PSC (2002b) indicated two independent, vertically stratified chlorinated solvent plumes. Further work by PSC (2005a) narrowed the extent of the plume, and work by PGG in 2006 and 2007 helped to define the plume and identify the source area beneath the southwest corner of the Blaser building. As a result, Blaser became the lead business for interim VI measures for some properties downgradient of their facility. Blaser completed soil source control in December 2007 (PGG, 2008a). The Blaser investigations identified TCE as the primary contaminant of concern for VI. PSC investigations in the W4 Investigation Area also identified VOC source areas at Art Brass Plating (ABP) (5516-3rd Avenue South) and Capital Industries (Capital; nd Avenue S). As with Blaser, ABP and Capital became the lead businesses for interim VI in the W4 Investigation Area. In order to establish a consistent interim process to assess and mitigate potential VI threats in the W4 Investigation Area, PSC, ABP, Blaser, and Capital jointly prepared (at Ecology s request) an Interim VI Plan (Arrow et al. 2007). The Interim VI Plan lists the Ecology-identified buildings assigned to each lead business, proposes an interim VI approach with Ecology-approved methodologies from PSC s IPIM Program for consistent implementation by each lead business. Although Blaser endeavors to explicitly implement PSC-developed methodologies, Blaser sitespecific conditions including, but not limited to new groundwater concentration data, plume dimensions, and improved sampling techniques may indicate a need to re-assess the VI IM&M schedule proposed herein. This discussion will be included in the VI Assessment Work Plan. BLASER VI IM&M WORK PLAN 1 AUGUST 7, 2008

7 1.2 LOCATIONS The Interim VI Plan lists 11 buildings where Blaser is responsible for conducting interim VI activities. The locations are shown on Figure 2. The buildings can be divided into two categories as follows: Four buildings are at various stages of VI assessment ( Mead St., nd Ave, 211 S. Orcas St., and 308 S. Orcas St). In accordance with the requirements of the Enforcement Order, Blaser is developing a separate VI Assessment Work Plan to address future activities associated with those locations. Seven buildings already have VI mitigation systems installed and operating. This Work Plan specifically addresses VI IM&M activities to be conducted at these seven buildings. Building information is summarized in Table 1. If VI mitigation systems are installed in any of the four buildings currently under assessment, the VI IM&M methodology presented herein will be applied. 1.3 MITIGATION SYSTEMS The VI mitigation systems operating at the seven buildings addressed in this work plan were installed and started up by PSC in 2003; except for the Blaser Office system, which was installed by Advanced Radon Technologies in February, PSC describes IPIM mitigation designs in The Depressurization Design Document: A Supplemental Inhalation Pathway Interim Measures Work Plan (PSC, 2003). Prior to installation, diagnostic testing is performed to determine the size of the depressurization system required for each building. Two types of VI mitigation designs were implemented: subslab depressurization system (SSDS) and sub-membrane depressurization system (SMDS). The purpose of the SSDS and SMDS are to depressurize the soil directly below the slab or vapor barrier by maintaining a field of negative pressure by evacuating soil gases with exhaust fans. The generation of this negative pressure field captures soil gases and vents it to the ambient air. The SSDS is applicable to slab-on-grade building and buildings with basements. An SSDS depressurizes the ground immediately below the slab with a radius of influence largely dependant on the exhaust rate. One or more sumps are created beneath the slab, which are linked via piping to one or more exhaust fans. The exhaust fan operates continuously, pulling soil gas from the sump(s) and venting them to the ambient air above the roof of the building via an exhaust stack. A dedicated manometer located between the fan inlet and outlet measures the pressure differential (in inches of water column). The effectiveness of an SSDS to induce a negative pressure field can be quantified by performing a Pressure Field Extension (PFE) test. For buildings with crawl spaces SMDS are applicable. Perforated pipes are positioned on the ground surface in the crawl space and connected to a non-perforated riser pipe. The perforated pipes are then covered by a vapor barrier. A fan exhausts captured soil gas to the ambient air via an exhaust stack. A dedicated manometer located between the fan inlet and outlet measures the pressure. A PFE test can not be performed on a SMDS. Appendix A provides as-built information on the seven operating systems, including plan and crosssection diagrams showing the locations of system components in each building. Note that original PSC reports for 132 and 134 S. Mead St. contain the same as-built diagrams as 128 S. Mead St. Only one set of as-built diagrams is included for the Mead St. residences. BLASER VI IM&M WORK PLAN 2 AUGUST 7, 2008

8 2.0 INSPECTION AND MONITORING 2.1 PREVIOUS INSPECTION AND MONITORING Initial confirmation of system performance was conducted in accordance with the Depressurization Design Document (PSC, 2003) and the Verification of Depressurization System Effectiveness and Long Term Operations and Maintenance Plan for Inhalation Pathway Interim Measure (Long-Term O&M Plan) (PSC, 2005b). The following sections describe the post-im inspection and monitoring at the seven buildings. Inspection and monitoring results are compiled in Table Pressure Field Extension Tests Pressure Field Extension tests were conducted by PSC on the initial startup of SSD systems to confirm that the mitigation system is effectively generating negative pressure beneath the entire slab. The through-slab pressure differential is monitored at test holes located at the far reaches of the building. A pressure differential of inches of water column or greater is acceptable. PSC s long-term operation and maintenance plan calls for PFE tests on a biennial basis. Advance Radon Technologies performed PFE testing at the Blaser Building (5700 3rd Ave) in The test holes are plugged between monitoring events Indoor Air Quality Monitoring Air quality monitoring was conducted by PSC following system installation at select locations, to confirm that mitigation measures were effective. PSC divided the six residential buildings into three long-term monitoring (LTM) groups. PSC s plan called for sampling LTM group 1 at a rate of one location every two years, beginning with 134 Mead St. in 2005, sampling 215 S. Orcas St in 2009, and 217 S. Orcas St in Indoor air was sampled at 227 S. Orcas St in March, PSC and PGG have conducted indoor air quality sampling at the Blaser Office Building ( rd Ave) six times for nine samples between 2005 and 2007 (PGG, 2008b) Tenant Manometer Checks PSC sent quarterly reminders to tenants or property owners to check the status of the manometer associated with their buildings VI mitigation system. They were encouraged to call PSC if the manometer levels were even or zero, indicating improper operation of the system. PGG field checked the manometer at 227 S. Orcas St and the Blaser Office Building (5700 3rd Ave) twice in Annual Inspections PSC used standardized inspection forms to be completed on an annual basis by PSC representatives during on-site inspections of the buildings. The PSC inspections recorded manometer readings, the condition of accessible VI systems components, and looked for any significant structural changes to the buildings that may affect the effectiveness of VI systems. Annual inspections of this type were conducted by PSC in 2005 and 2006 at 128, 132, and 134 Mead St, and 215, 217, and 227 S. Orcas St. Manometer readings at the Blaser Office Building ( rd Ave) were recorded twice in 2007 and once in RGA Environmental conducted an indoor air VOC survey of the office at Blaser in Manometer readings are summarized in Table 2. BLASER VI IM&M WORK PLAN 3 AUGUST 7, 2008

9 2.2 PROPOSED INSPECTION AND MONITORING The inspection and monitoring schedule proposed by Blaser is shown in Table 1. The schedule is consistent with PSC s plan for the six residential buildings with modifications and Blaser s Office Post- Mitigation Plan (PGG, 2008b) for the Blaser Office Building (5700 3rd Ave). During 2007 when the lead business changed from PSC to Blaser for the six residential buildings, inspection and monitoring were not performed while the Interim Vapor Intrusion Plan (Arrow et al., 2007) was being written. Blaser is directed to adopt the prescribed methods and conduct the assigned tasks under the approved Interim Vapor Intrusion Plan in Section 5 of Exhibit B of the Enforcement Order. Proposed inspection and monitoring activities include a combination of annual inspections, PFE tests, indoor air quality monitoring, and quarterly tenant manometer checks. Annual inspections, PFE tests, and indoor air quality monitoring will be conducted during the winter heating season months between October and March, during which time VI potential may be at a maximum Pressure Field Extension Tests PFE tests will be performed in 2008 following PSC protocol on residential SSD systems at 215, 217, and 227 S. Orcas St. A PFE test will be conducted as determined to be necessary based on indoor air source investigations at the Blaser Office Building as per Blaser s Office Post-Mitigation Plan (PGG, 2008b) Indoor Air Quality Monitoring Indoor air quality monitoring for 215, 217, and 227 S. Orcas St will be conducted in 2008 after PFE tests are concluded. Blaser proposes to shift indoor air quality sampling that was missed in 2007 at 217 S. Orcas St to winter 2008 to A sampling and analysis plan (SAP) will be included in the VI Assessment Work Plan. Site-specific sampling information will be communicated to Ecology prior to sampling, and will include: the number of samples to be collected and sampling locations. Indoor air quality monitoring at the Blaser Office building is scheduled for 2008 as per Blaser s Office Post-Mitigation Plan (PGG, 2008b). The initial long-term monitoring plan drafted by PSC (2005b) scheduled indoor air sampling during the winter of 2007 and the winter of 2009 for 128 and 132 Mead St., respectively. However, in the Interim VI Plan (Arrow et al., 2007) the VI scope is for annual inspections at 132 and 134 S. Mead St, and groundwater sampling and analysis near 128 S. Mead St. Consistent with previous agreements between Ecology and PSC, when shallow groundwater concentrations beneath a building are significantly below CCEFs or NCCEFs of 10, Ecology permitted PSC to forego scheduled indoor air sampling in buildings with operating VI mitigation systems. The rationale expressed is that if the shallow groundwater COC concentrations are below the action level, there is an incomplete VI migration pathway, and the VI mitigation system has no practical significance. So, it is fruitless to sample indoor air. This rationale can also be applied to PFE tests. Similarly, Blaser may use groundwater results that indicate an incomplete VI migration pathway in lieu of performing indoor air quality monitoring and PFE tests. This information will be reported to Ecology at least 30 days prior to the scheduled indoor air quality sampling event or PFE test. BLASER VI IM&M WORK PLAN 4 AUGUST 7, 2008

10 2.2.3 Tenant Manometer Checks Blaser will continue PSC s practice of mailing quarterly reminders to building tenants and/or property owners instructing them to check the mitigation system manometer. A copy of Blaser s reminder notice is included in Appendix C Annual Inspections Annual inspections will be conducted at the same time of year at the six residential properties if possible. Blaser will adopt the ABP s revised PSC inspection forms (Aspect, 2008) that separate the questions for the SSDS and SMDS (Appendix B). Aspect wisely added a box for manometer readings, and a box for the previous manometer reading. With this information the inspector can readily assess significant changes in the readings, and directly troubleshoot possible problems. If permitted by property owner, photographs will be taken to further document the conditions of the building and VI mitigation systems and appurtenances. 3.0 RE-EVALUATION/ENHANCEMENT OF MITIGATION SYSTEMS The results of annual inspections, indoor air quality monitoring and/or PFE testing may expose problems with VI mitigation system effectiveness. It may become necessary to re-evaluate and possibly enhance system effectiveness. Re-evaluation and possibly enhancement of VI mitigation system effectiveness process will be conducted on a case-by-case basis in the event that one of the following criteria is met: A significant structural change in the building. In the event of a significant structural change is observed in a building, Blaser will contact Ecology within 3 weeks of the building inspection date to discuss the site conditions and propose steps to address the problem. Air quality monitoring results that indicate an indoor air IPIMAL exceedance in the absence of introduced indoor sources. If indoor air quality sampling results indicate the need for system reevaluation, Ecology will be contacted within 3 weeks of receiving analytical laboratory results A minimum tenfold increase in groundwater VOC concentrations in the vicinity of the buildings. The evaluation and reporting will be performed each time groundwater in these wells is sampled as per Blaser s Groundwater Monitoring Plan (PGG, 2008d, in preparation). If groundwater sampling results indicate the need for system re-evaluation, Ecology will be contacted within 3 weeks of receiving analytical laboratory results. See Figure 2 for ground water table monitoring well locations near to the buildings discussed herein. Existing groundwater monitoring well BDC-1-WT and proposed monitoring wells BDC-8-WT and BDC-10-WT (RI Work Plan, PGG 2008c) will be used to evaluate significant increases in COC concentrations at buildings B1 to B3. Monitoring wells BDC-4-WT and BDC-3-WT will be evaluated for the Blaser Office, and proposed monitoring well BDC-11-WT for B5 to B SYSTEM MAINTENANCE There is no regularly-scheduled maintenance associated with VI mitigation systems, but will be performed as-needed. Exhaust fans are the primary component that would fail on the SMDS and SSDS. These fans are relatively inexpensive and readily replaceable. If annual inspections indicate reduced fan effectiveness such as noise, vibration, or significantly reduced manometer readings, then these units will be replaced directly without triggering a full system re-evaluation. Other common system BLASER VI IM&M WORK PLAN 5 AUGUST 7, 2008

11 maintenance that may need to be performed includes replacing damaged system piping and repair/reseating of SMDS vapor barriers. Maintenance is generally initiated by conditions observed during annual inspections or by calls from the building tenant. 3.2 SYSTEM SHUTDOWN The VI Assessment Work Plan will discuss how periodic groundwater monitoring results are evaluated to determine whether VI mitigation systems are candidates for shutdown. If a system is identified for shutdown, Blaser would draft a letter to Ecology proposing shutdown procedures and postshutdown monitoring. 4.0 VI IM&M REPORTING Blaser shall report the results of all annual system inspections, manometer readings, and PFE tests in a short progress report within 30 days of completion. Indoor air sampling results will be reported within 60 days of completion. In addition, any potentially significant change of conditions, as per section 3.0 above, will be discussed in a timely manner with Ecology. Each scheduled indoor air quality monitoring event and report formatting will follow the SAP included in the VI Assessment Work Plan. Site-specific concerns such as sampling location and number of samples will be communicated to Ecology. Monitoring results will be compared to any previous pre- or post-mitigation monitoring results, and to indoor air IPIMALs (to be discussed in the VI Assessment Work Plan). The SAP for the Blaser Office Building ( rd Ave) is included in the Blaser s Office Post-Mitigation Plan (PGG, 2008b). The evaluation of groundwater monitoring results discussed in this Work Plan under section 3.0 should be reported in groundwater monitoring reports, and not as part of VI IM&M reporting. 5.0 REFERENCES Arrow, et al., 2007, Interim Vapor Intrusion Plan, West of 4th Avenue South Investigation Area, Seattle, Washington, Arrow Environmental, LLC (for PSC), Aspect Consulting, LLC (for ABP), Farallon Consulting, LLC (for Capital Industries), and Pacific Groundwater Group (for Blaser Die Casting), July 20, Aspect Consulting, 2008, Vapor Intrusion Inspection, Monitoring, and Maintenance Work Plan, Art Brass Plating. February 28, 2008 (Draft with Comments from Ecology and responses from Aspect, May 27, 2008). Pacific Groundwater Group (PGG), 2006, Blaser Die Casting, Soil and Groundwater Investigation Report, October 30, PGG, 2008a, Blaser Source Control Report Blaser Die Casting, January 23, PGG, 2008b, Blaser Office Post-Mitigation Plan, rd Ave South, Seattle, Washington, May 28, PGG, 2008c, Blaser Die Casting, Draft Remedial Investigation Work Plan, February 28, PGG, 2008d, Draft Blaser Groundwater Monitoring Plan, in preparation. BLASER VI IM&M WORK PLAN 6 AUGUST 7, 2008

12 PSC, 2002a, Revised Inhalation Pathway Interim Measures Work Plan. August 12, 2002, and Errata Document, September 17, PSC, 2002b, Technical Memorandum VIII: Results of the Supplemental Off-Site Groundwater Characterization & Proposed Monitoring Well Locations, April 15, PSC, Philip Services Corporation. Final Depressurization Design Document: A Supplemental Inhalation Pathway Interim Measures Work Plan, May PSC, 2005a. Inhalation Pathway Interim Measure Tier 3 Sampling Report for rd Avenue S., Seattle, Washington. November 14, PSC, 2005b, Verification of Depressurization System Effectiveness and Long Term Operations and Maintenance Plan for Inhalation Pathway Interim Measures, April Washington State Department of Ecology Toxics Cleanup Program. March 3, Model Toxics Control Act Cleanup Regulation Chapter WAC. BLASER VI IM&M WORK PLAN 7 AUGUST 7, 2008

13 Table 1. Proposed Inspection and Monitoring Schedule VI Mitigation System Type LTM Group Location ID (1) Building Address Use (2) System Inspection (3) PFE Monitoring (4)(5) Air Quality Monitoring Tenant Manometer Checks SSDS 1 B1 215 S. Orcas St R SSDS/SMDS B2 217 S. Orcas St R 2 SSDS B3 227 S. Orcas St R SSDS 3 B rd Ave South C Winter Winter Winter Winter Winter Winter Winter Winter Winter (a) SMDS B5 128 S. Mead R ns Quarterly SMDS 4 B6 132 S. Mead R Winter ns Quarterly SMDS B7 134 S. Mead R Winter ns Quarterly C Commercial R Residential SMDS Sub-membrane depressurization system SSDS Sub-slab depressurization system LTM Long-term monitoring VI Vapor intrusion Notes: (1) Ecology-identified location, per Table 2 of the Interim VI Plan (Arrow et al., 2007). (2) For buildings that have more than one use, the most restrictive use (e.g., residential) is listed. (3) This column refers to formal inspections by Blaser representatives. In addition, quarterly mailed reminder notices notify tenants to check the VI system manometer (4) PFE tests will be conducted on a biennial basis, or every two years. (5)Negative pressure field extension cannot be measured for SMD systems. (a) Contingent on Blaser Office Post-Mitigation Work Plan (PGG, 2008b) approved schedule ns not scheduled for air quality monitoring as per Arrow et al., 2007 and/or PSC, 2005b Winter includes the winter months of Nov. and Dec. of 2008, and Jan. and Feb. of Winter Winter ns Winter (a) Quarterly Quarterly Quarterly Quarterly

14 Table 2. Previous Indoor Air Quality, Manometer, and Pressure Field Extension VI Mitigation System Type LTM Group Location ID (1) Building Address Air Quality Monitoring Date Initial Inches H2O Manometer Readings SSDS 1 B1 215 S. Orcas St None 10/14/ /8 10/14/2003 SSDS/SMDS B2 217 S. Orcas St None 11/13/ /8 11/13/2003* 2 SSDS B3 227 S. Orcas St Mar-06 7/14/ /14/2003 SSDS 3 B rd Ave South October 2005, March 2006, May, 2006, September 2006, July 2007, October 2007 February 2006 SMDS B5 128 S. Mead None 10/23/ SMDS 4 B6 132 S. Mead None 9/25/ SMDS B7 134 S. Mead None 9/25/ Date Inches H2O Date Inches H2O Date /20/ /5/ Feb-06 PFE Test Results Negative Pressure Readings (inches H2O)(2) at each Test Hole (3) PFE-1 PFE-2 PFE PFE-1 PFE PFE-1 PFE-2 PFE-3 PFE PFE-1 PFE-2 PFE not applicable SMDS Sub-membrane depressurization system SSDS Sub-slab depressurization system Notes: (1) Ecology-identified location, per Table 2 of the Interim VI Plan (Arrow et al., 2007). (2) Ecology performance criteria of inches H2O or greater. (3) For test hole locations, see Appendix A. * Due to the uneven surfaces in the crawl space and the rigidity of the membrane material, it is not possible to get the tight seal needed to perform diagnostic testing in crawl space systems. Therefore, diagnostic testing was not performed in this portion of the system.

15 E l l i o t t B a y 90 P u g e t S o u n d D u w a m i s h R i v e Blaser Die Casting r 4th Ave S S Lucile St 5 K:\JANET\JK0504 BlaserDieCasting\GIS\mxds\VicinityMap.mxd - 1/9/ Miles 1 Figure 1 Vicinity Map Blaser Die Casting JK0504

16 S FINDLAY ST 20 S ORCAS ST B5 B6 B7 B1 B2 B3 B4 3RD AVE S Blaser Die Casting 4TH AVE S 2ND AVE S 16 Mead Street Building S MEAD ST Figure 2 Blaser Lead Business Site Map Parcels Buildings addressd in VI Assessment Work Plan Buildings addressd in VI Inspection, Maintenance and Monitoring Work Plan Buildings with vapor intrusion mitigation system B4 Ecology identified building (Arrow et al. 2007) Blaser Die Casting 0 Feet USGS Orthophoto JK0504

17 BLASER VI IM&M WORK PLAN AUGUST 7, 2008 APPENDIX A AS-BUILT DIAGRAMS OF VI MITIGATION SYSTEMS

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26 BLASER VI IM&M WORK PLAN AUGUST 7, 2008 APPENDIX B ANNUAL INSPECTION FORMS

27 Form 1 - Sub-Slab Depressurization System Inspection Form Date: Time: Address: PART 1 - DOCUMENTATION OF CONDITION OF SYSTEM COMPONENTS Manometer Readings Date In.H 2 O Exterior Pipe Free of Cracks Y N N/A Interior Pipe Free of Cracks Y N N/A Fan Running Appropriately (no excess vibration or noise) Y N N/A Caulk on Floor Penetrations in Good Condition Y N N/A Manometer in Good Condition Y N N/A Roof Flashing in Good Condition Y N N/A Significant basement floor cracking, or new openings in the floor Y N N/A Significantly different manometer readings Y N N/A PART 2 - DOCUMENTATION OF STRUCTURAL CHANGES Any Significant changes to the building's HVAC System Y N N/A Any new vents or openings in the roof/walls, less than 10' away from the stack (and <2' below it) Y N N/A Any changes to the use of any chimneys that could result in re-entrainment Y N N/A Any new buildings near the mitigated building close enough that stack gasses could contaminate their indoor air Y N N/A Has the attic been remodeled into a living space (if the mitigation fan is located in the attic) Y N N/A Have there been any signifcant earthquake events Y N N/A PART 3 - OTHER OBSERVATIONS/COMMENTS Inspected by: (Signature) (Printed Name) Aspect Consulting 2/28/2008 Form 1 V:\ Art Brass Plating\RI Work Plan\Vapor Intrusion Inspection, Monitoring, and Maintenance\VI IM&M WP Tables & Forms Page 1 of 1

28 Form 2 - Sub-Membrane Depressurization System Inspection Form Date: Time: Address: PART 1 - DOCUMENTATION OF CONDITION OF SYSTEM COMPONENTS Manometer Readings Date In.H 2 O Exterior Pipe Free of Cracks Y N N/A Interior Pipe Free of Cracks Y N N/A Fan Running Appropriately (no excess vibration or noise) Y N N/A Membrane Material in Good Condition Y N N/A Membrane Seals in Good Condition Y N N/A Manometer in Good Condition Y N N/A Roof Flashing in Good Condition Y N N/A Significantly different manometer readings Y N N/A Any evidence that the membrane has been walked on, moved, or otherwise tinkered with Y N N/A Any holes in the membrane, broken seals, etc. Y N N/A PART 2 - DOCUMENTATION OF STRUCTURAL CHANGES Any Significant changes to the building's HVAC System Y N N/A Any new vents or openings in the roof/walls, less than 10' away from the stack (and <2' below it) Y N N/A Any changes to the use of any chimneys that could result in re-entrainment Y N N/A Any new buildings near the mitigated building close enough that stack gasses could contaminate their indoor air Y N N/A Has the attic been remodeled into a living space (if the mitigation fan is located in the attic) Y N N/A Have there been any signifcant earthquake events Y N N/A PART 3 - OTHER OBSERVATIONS/COMMENTS Inspected by: (Signature) (Printed Name) Aspect Consulting 2/28/2008 Form 2 V:\ Art Brass Plating\RI Work Plan\Vapor Intrusion Inspection, Monitoring, and Maintenance\VI IM&M WP Tables & Forms Page 1 of 1

29 BLASER VI IM&M WORK PLAN AUGUST 7, 2008 APPENDIX C MANOMETER CHECK REMINDER

30 REMINDER Please check periodically to make sure your depressurization system is working properly. Do this by looking at the fluid level in your manometer. If the fluid level on each side makes an uneven U, as shown in the picture to the left, then the system is working properly. However, if the fluid level on each side is of the U is even, then please call so that we can make arrangements to fix any problems. Temporary problems with the system would not indicate any additional health risks- we just need to make sure the system is operating correctly. Thank you for your cooperation, Janet Knox Principal Hydrogeologist Pacific Groundwater Group (206)

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