Using Vapor Intrusion Subslab Barriers. Rob Carvahlo and Amanda Petrocelli EAI, Inc.

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1 Using Vapor Intrusion Subslab Barriers Rob Carvahlo and Amanda Petrocelli EAI, Inc.

2 LINING TECHNOLOGIES REMEDIATION TECHNOLOGIES DRILLING SYSTEMS BUILDING ENVELOPE CONTRACTING SERVICES FOR PROTECTION AGAINST VAPOR INTRUSION Amanda Petrocelli Robert Carvalho October 11,

3 Agenda Gas Vapor Mitigation Options Chemical/Physical Properties Diffusion Testing CETCO Offerings Gas Vapor Barrier Systems Gas Venting Systems Quality Control Case Studies by EAI 3

4 The Risk: Vapor Intrusion Vapor intrusion is the migration of subsurface chemical vapors into overlying structures. Vapors may include: Volatile organic compounds (VOCs) Semi-volatile organic compounds Inorganics (i.e.. mercury, hydrogen sulfide, etc.) Methane Radon Naturally-occurring / man-made contaminants Vapor intrusion and indoor air risk occurs when you have: A source An inhabited building A pathway from the source to the inhabitants Vapor intrusion has become a significant environmental issue for regulators, industry leaders, and concerned residents nationwide. 4

5 The Risk: Vapor Intrusion Current lack of knowledge about indoor air issues and evaluation techniques may oversimplify the problem and may cause air quality investigations and subsequent risk assessments to understate or overstate the problem. Indoor air quality is overlooked in many environmental site investigation and soil or groundwater plume contamination scenarios. Lack of knowledge regarding indoor air quality issues and cost considerations tend to contribute to the omission of indoor air sampling and evaluation. ITRC CETCO offers: Solutions for various site conditions, backed by extensive track record/case history Experienced technical managers with knowledge on current industry trends Technical and design assistance for gas vapor membrane and venting systems World-class Research & Development facility Design-build capabilities 5

6 GAS VAPOR MITIGATION OPTIONS 6

7 Two Types of Gas Vapor Barriers (per ITRC Guidance) Gas vapor barrier options include: Sheet-applied, batten and welded 60 mil - HDPE Spray-Applied Membranes 60 mil - Liquid Boot 7

8 Physical Properties of Liquid Boot (spray-applied) * * * * Physical Property Test Method Result Bonded Seam Strength Tests ASTM D6392 Passed Heat Aging- average tensile strength change, average tensile stress change, average elongation change, bonded seams ASTM D Dead Load Seam Strength City of Los Angeles Passed Environmental Stress-Cracking ASTM D Passed Soil Burial ASTM E Passed Passed Elongation ASTM D412 1,332% - Ø reinforcement, 90% recovery Tensile Strength ASTM D p.s.i. without reinforcement Tensile Bond Strength to Concrete ASTM D413 2,707 lbs/ft 2 uplift force Water Vapor Permeability ASTM E perms Water Vapor Transmission ASTM E grains/h-ft 2 * City of Los Angeles approval for 60-mil Liquid Boot Gas Vapor Barrier 8

9 Chemical Properties of Liquid Boot (spray-applied) Chemical Property Test Method Result Acid Exposure (10% H2SO4 for 90 days) ASTM D543 Less than 1% weight change Diesel (1000 mg/l), Ethylbenzene (1000 mg/l), Naphthalene (5000 mg/l) and Acetone (500 mg/l) Exposure for 7 days ASTM D543 Less than 1% weight change, Less than 1% tensile strength change Radon Permeability Tested by US Dept. of Energy Zero permeability to Radon (222Rn) * * * Micro Organism Resistance (Soil Burial) ASTM D Passed* Methane Permeability ASTM Passed* Oil Resistance Test- average weight change, average tensile strength change, average tensile stress change, average elongation change, bonded seams, methane permeability ASTM D PCE Diffusion Coefficient Tested at 6,000 mg/m x m 2 /sec TCE Diffusion Coefficient Tested at 20,000 mg/m x m 2 /sec Benzene Diffusion Coefficient Tested at 43,000 mg/m x m 2 /sec Passed* * City of Los Angeles approval for 60-mil Liquid Boot Gas Vapor Barrier 9

10 Membrane Diffusion Test Modified ASTM E96 The diagram illustrates how the diffusion coefficients on the Liquid Boot membrane for PCE, TCE and Benzene were determined CETCO R&D facility is capable of performing these tests 10

11 Fick s Law Applying diffusion test data into the Fick s Law equation results in the diffusion coefficient: E= A(C source - C g0 )D cz eff / L cz where E = Rate of mass transfer, g/s A = Cross-sectional area through which vapors pass, cm 2 C source = Vapor concentration within the capillary zone, g/cm 3 -v C g0 = A known vapor concentration at the top of the capillary zone, g/cm 3 -v (C g0 is assumed to be zero as diffusion proceeds upward) D cz eff = Effective diffusion coefficient across the capillary zone, cm 2 /s L cz = Thickness of capillary zone, cm 11

12 Diffusion Test Results Summary Test Conditions Average Solvent Diffusion Rate Membrane Area Membrane Thickness Calculated Diffusion Coefficient PCE 6,000 mg/m mg/day 1.45 x 10-2 m x 10-3 m 2.74 x m 2 /sec TCE 20,000 mg/m mg/day 1.48 x 10-2 m x 10-3 m 8.04 x m 2 /sec 13,000 mg/m mg/day 1.48 x 10-2 m x 10-3 m 1.4 x m 2 /sec 136,000 mg/m 3 19 mg/day 1.48 x 10-2 m x 10-3 m 1.9 x m 2 /sec 12

Venting Systems (Used In Conjunction with a Gas Vapor Barrier per ITRC Guidance) Passive Venting

active, if needed, to reduce vapor concentrations Should be properly designed to allow adequate

alter and maintain pressure gradients & redirect subsurface gas flow Major system components

13 Venting Systems (Used In Conjunction with a Gas Vapor Barrier per ITRC Guidance) Passive Venting Rely on nature pressure differentials to vent the subsurface gas Can be designed to be converted to active, if needed, to reduce vapor concentrations Should be properly designed to allow adequate flow of vapors Evaluation of air flow should be conducted Active Venting Use of mechanical means to alter and maintain pressure gradients & redirect subsurface gas flow Major system components generally include gas extraction wells and piping, vacuum blowers, and gas/vapor treatment or reuse systems 13

14 CETCO SYSTEM OFFERINGS 14

15 CETCO System Offerings Liquid Boot Gas Vapor Barrier System Liquid Boot Plus High-Performance Gas Vapor Barrier System Coreflex Methane Barrier & Waterproofing System GeoVent Gas Venting System 15

16 LIQUID BOOT GAS VAPOR BARRIER SYSTEM 16

17 Liquid Boot System Description: Liquid Boot is a cold, spray-applied membrane that acts as a gas vapor barrier and damp-proof membrane. Typical Uses: Applied under slab and on below grade vertical walls as a gas vapor barrier to minimize vapor and nuisance water (non-hydrostatic conditions) migration into buildings Ideal for methane migration control Concrete water tank and reservoirs liner to prevent water seepage into concrete Applied as a liner to concrete canals for rehabilitation Agency Approvals: City of Los Angeles Research Report # Approved for Liquid Boot Membrane for Gas Barrier County of Los Angeles Department of Public Works Approved for Liquid Boot Application as a Methane Gas Barrier NSF International-NSF/61 Approved for Potable Water Tank Liner for tanks >300,000 gallons 17

18 Liquid Boot System Components and Features: GeoVent TM Gas Venting System Low profile; no trenching required Liquid Boot BaseFabric T-40/T-60 (fabric selection depends on site conditions) Heat bonded non-woven geotextile Liquid Boot Two component spray applied membrane (60 mils typical) Water based - No VOCs, odorless Bonds to most surfaces eases detailing Seamless - eliminating membrane failures Rapid curing - reducing construction time High strength and elongation durable Liquid Boot UltraShield Series Protection Course G Series - Needle-punched, nonwoven geotextile P Series - HDPE Polyethylene geomembrane Adheres to the underslab providing superior tensile strength 18

19 Liquid Boot PILE CAPS AND FOOTINGS PENETRATIONS 19

20 Liquid Boot VERTICAL SURFACE ATTACHMENTS 20

21 Liquid Boot TYPICAL SYSTEM INSTALLATION 1. Liquid Boot applied to BaseFabric 2. Penetrations Detailed 3. UltraShield Protection Fabric 21

22 LIQUID BOOT PLUS HIGH-PERFORMANCE GAS VAPOR BARRIER SYSTEM 22

23 Liquid Boot Plus System Description: The Liquid Boot Plus Gas Vapor Barrier system is a multi-layer and high-performance, cold spray-applied membrane that acts as a gas vapor barrier and damp-proof membrane. Typical Uses: Installed under slab and on below grade vertical walls as a gas vapor barrier to minimize vapor and nuisance water (non-hydrostatic conditions) migration into buildings Ideal for applications with chlorinated solvents, BTEX and other PAHs Agency Approvals: City of Los Angeles Research Report # Approved for Liquid Boot Membrane for Gas Barrier County of Los Angeles Department of Public Works Approved for Liquid Boot Application as a Methane Gas Barrier 23

24 Liquid Boot Plus System Components and Features: GeoVent Gas Venting System Low profile; no trenching required Liquid Boot VI-20 Geomembrane EVOH composite geomembrane - 20x lower VOC diffusion than 80 mil HDPE Liquid Boot VI-20 Detailing Fabric Liquid Boot Two component spray applied membrane (60 mils typical) Water based - No VOCs, odorless Bonds to most surfaces eases detailing Seamless - eliminating membrane failures Rapid curing - reducing construction time High strength and elongation - durable Liquid Boot UltraShield Series Protection Course G Series - Needle-punched, nonwoven geotextile P Series - HDPE Polyethylene geomembrane Adheres to the underslab providing superior tensile strength 24

25 Liquid Boot VI-20 Geomembrane Tested by Dr. Kerry Rowe, Queens University, Ontario Author of the POLLUTE model Well-known in geosynthetics industry Determined upper bound partition and diffusion coefficients Aqueous phase diffusion coefficient of co-extruded geomembrane Liquid Boot VI mil HDPE Contaminant Diffusion Coefficient (m 2 /s) Diffusion Coefficient (m 2 /s) Benzene 9.0 x x Ethyl Benzene 8.0 x x Toluene 8.5 x x O-Xylene 7.5 x x

applications for EVOH is in automotive fuel systems to control emissions of hydrocarbons The use of EVOH in a co-extrusion blow-molded tank with molecular

26 EVOH Geomembrane Technology Liquid Boot VI-20 geomembrane is a layer of EVOH between two layers of polyethylene. EVOH is a copolymer of: Polyethylene (extrudes easily and improves bonding) Polyvinyl Alcohol and Ethylene Vinyl Alcohol (provides gas barrier) Major applications for EVOH is in automotive fuel systems to control emissions of hydrocarbons The use of EVOH in a co-extrusion blow-molded tank with molecular weight HDPE originated in the US in response to mandates of VOC emissions reductions by the US EPA and the CA Air Resources Board (CARB) and is has been in widespread use globally for more than 15 years. 26

27 EVOH Geomembrane Technology Development started in 1989 in response to EPA and CARB mandates Emissions regulations have progressively become tighter each decade EVOH became barrier of choice due to VOC barrier properties Emissions through tank shell are <10mg/24hrs Regulation Agency Tier 1 EPA LEV 1 - CARB LEV 2 - CARB Allowable Emissions 2000mg/test 3 day diumal 2000mg/test 3 day diumal 500mg/test 3 day diumal PZEV - CARB 350mg/test 3 day diumal Allowable emissions from entire vehicle over service life (100, ,000 miles) EVOH polymer is highly resistance to Trichloroethylene because they are INSOLUBLE. (TCE-19.0 MPa EVOH-38.9 MPa) Polyvinylchloride polymer will likely dissolve in Trichloroethylene because they are SOLUBLE. (PVC-19.6 MPa TCE-19.0 MPa) Solvent Solubility Parameter (SI) [MPa] Polymer Solubility Parameter (SI) [MPa] Dichloromethane ,2 Dichloromethane 20.0 Trichloroethylene 19.0 Benzene 18.7 Toluene 18.2 Ethyl benzene 18.0 M-Xylene 18.0 Polypropylene 16.2 Polyethylene 16.4 Polyvinylchloride 19.6 Polyurethane 20.5 Nylon Nylon EVOH (32mol%) 38.9 Water

28 Liquid Boot Plus PILE CAPS AND FOOTINGS PENETRATIONS 28

29 GEOVENT GAS VENTING SYSTEM PRESSURE RELIEF COLLECTION AND VENTING SYSTEM (PRCVS) 29

30 Passive Gas Venting Options Types of Passive Venting Systems: Trenched Installations Pipe and gravel Installation directly on subrade Low-profile GeoVent 30

31 GeoVent Gas Venting System System Description: The GeoVent system is a modular prefabricated gas venting layer designed to improve venting efficiency and reduce installation costs. Typical Use: To provide an active or passive under slab gas venting system System Components and Features: GeoVent Installed directly on subgrade eliminating costly trenching Placed in closer proximity to the gas vapor barrier allowing for more effective venting Greater opening area per lineal foot of pipe and integral filter fabric allowing for higher ventilation efficiency Installed at a higher elevation reducing susceptibility to inundation from perched groundwater that may accumulate beneath the building foundation Flow characteristics meet or exceed that of a typical trenched installation. The overall capacity of the system is far in excess of typical gas flux rates. Specialty Connecting Pieces: End Outlets, Interior Footing Sleeves 31

32 Design Consideration Venting systems should be properly designed to adequately relieve pressure and reduce gas concentrations from beneath the structure CETCO provides gas venting performance data CETCO provides assistance with the design of these types of systems 32

33 GeoVent Gas Venting System Details TYPICAL PLAN VIEW CONNECTION TO A VENT RISER 33

34 GeoVent Gas Venting System Installation TYPICAL SYSTEM INSTALLATION 1. GeoVent rolled out on subgrade 2. No trenching is required 3. GeoVent connection to vent riser 34

35 QUALITY CONTROL 35

36 Certified Installers and Inspectors As with any proper installation, it is important to perform QA/QC measure to ensure successful installations. QA/QC procedures are performed on CETCO systems using: Certified installers Certified inspectors Smoke testing 36

37 QA/QC with Smoke Testing 37

38 SUMMARY 38

39 Summary The EPA has developed and recommends using vapor intrusion models designed to evaluate risk. Guidance documents encourage the use of a spray-applied gas vapor barrier in conjunction with a passive/active venting system. EVOH technology is a high performance vapor intrusion technology offered exclusively in the Liquid Boot Plus system. CETCO provides 4 systems designed to meet the needs of your vapor intrusion projects. CETCO offers design assistance for each of the gas vapor barrier and venting systems we provide. Proper installation techniques and QA/QC procedures are executed on CETCO systems using certified installers and inspectors as well as smoke testing. To ensure your building is protected now and in the future, it is always best practice to install a gas vapor barrier and venting system. 39

40 CASE STUDIES 40

41 Introduction Vapor mitigation has become the standard operating procedure for most new buildings in the Northeast US. Vapor Intrusion can occur on any development/redevelopment of former industrial and manufacturing sites. EAI has worked on a number of large redevelopment sites, installing subslab mitigation systems, vapor barriers, and monitoring systems. 1. Fraternity Meadows Secaucus, NJ 2. Bayonne Crossings Bayonne, NJ 41

42 FRATERNITY MEADOWS Secaucus, NJ 42

43 Fraternity Meadows (Xchange Place) Secaucus, NJ Before 43

44 Site Background Located 10 miles from midtown Manhattan, the site is formerly known as Gallo landfill that encompasses 33.4 acres along the Hackensack river in the NJ Meadowlands. Redevelopment started in 2008 and is ongoing in phases. Vapor intrusion issue is landfill gas intrusion, mainly methane. The overall redevelopment encompasses 60 acres including a new large scale rail station, new turnpike extension, 50,000 SF retail space, 235 luxury condominiums, 800 market rate rentals, 85 low to moderate income rental units. To date, EAI has installed over 250,000 sq. ft. of sub slab vapor mitigation systems including sub slab depressurization systems, vapor barriers, and monitoring systems. 44

45 Site Background GC/Owner: Atlantic Realty/Fraternity Meadows, LLC Design Engineer: HydroQual EAI, Inc. s Scope of Work: LIQUID BOOT Vapor Barrier Installation Sub-slab Venting Installation Monitoring System Installation EAI installed the Liquid Boot vapor barrier underneath the slab of a residential development in Secaucus, NJ. Following the installation of the vapor barrier, EAI installed over 3 miles of reinforced tubing to provide sampling points for a methane gas monitoring system. 45

46 Surface Preparation Fraternity Meadows Secaucus, NJ 46

47 Stone and Subgrade Preparation Fraternity Meadows Secaucus, NJ 47

48 PVC Venting System Installation Fraternity Meadows Secaucus, NJ 48

49 LIQUID BOOT PVC Venting & Geovent Installation Fraternity Meadows Secaucus, NJ 49

50 T-60 Base Fabric Installation Fraternity Meadows Secaucus, NJ 50

51 LIQUID BOOT Installation Fraternity Meadows Secaucus, NJ 51

52 LIQUID BOOT Installation Fraternity Meadows Secaucus, NJ 52

53 LIQUID BOOT Installation Fraternity Meadows Secaucus, NJ 53

54 LIQUID BOOT Fraternity Meadows Secaucus, NJ 54

55 LIQUID BOOT Fraternity Meadows Secaucus, NJ 55

56 LIQUID BOOT Installed and Protected Fraternity Meadows Secaucus, NJ 56

57 Monitoring System Tubing Installation Fraternity Meadows Secaucus, NJ 57

58 3/8 Reinforced Nylon Tubing Fraternity Meadows Secaucus, NJ 58

59 Monitoring Installation Fraternity Meadows Secaucus, NJ 59

60 Fraternity Meadows (Xchange Place) Secaucus, NJ After 60

61 BAYONNE CROSSINGS Bayonne, NJ 61

62 Bayonne Crossings Before 62

63 Site Background Former legacy site of a major petroleum company has turned into Bayonne Crossings, located in Hudson County NJ. The former oil transfer and oil storage facility site encompasses 30 acres in Bayonne, NJ, with close proximity to NYC. Vapor intrusion concerns were volatile organic compounds (VOC s), chromium, and NAPL. The redevelopment includes over 400,000 SF of retail space and is anchored by Lowes, Wal-mart, Michaels, New York Sports Club, and a myriad of restaurants. EAI installed approximately 400,000 sq. ft. of sub-slab vapor mitigation systems including sub-slab depressurization systems, vapor barriers, and monitoring systems. 63

64 Site Background GC/Owner: Cameron Group, LLC Design Engineer: Langan Engineering EAI, Inc. s Scope of Work: Stone and sub-grade preparation UltraDrain 9000 Installation Sub-slab Venting Installation LIQUID BOOT Vapor Barrier Installation Monitoring System Installation EAI installed the Liquid Boot vapor barrier, along with sub-slab depressurization systems, and monitoring systems for various retail stores and restaurants in the Bayonne Crossings complex. 64

65 Site Preparation Bayonne Crossings Bayonne, NJ 65

66 Subgrade Preparation Bayonne Crossings Bayonne, NJ 66

67 Subgrade Preparation Bayonne Crossings Bayonne, NJ 67

68 Trenching for PVC Venting Bayonne Crossings Bayonne, NJ 68

69 PVC Sub-Slab Venting Installation Bayonne Crossings Bayonne, NJ 69

70 LIQUID BOOT GeoVent Installation Bayonne Crossings Bayonne, NJ 70

71 LIQUID BOOT Installation Bayonne Crossings Bayonne, NJ 71

72 Smoke Test Quality Control Bayonne Crossings Bayonne, NJ 72

73 Smoke Test Quality Control Bayonne Crossings Bayonne, NJ 73

74 G-1000 UltraShield Protection Layer Installation Bayonne Crossings Bayonne, NJ 74

75 UltraDrain Layer Installation Bayonne Crossings Bayonne, NJ 75

76 VI-20 Geomembrane Installation New York Sports Club Bayonne, NJ 76

77 Bayonne Crossings Bayonne, NJ After 77

78 SUMMARY 78

79 Summary These sites deal with a variety of complex issues, as any other large scale vapor mitigation project would. By complying with strict plans and specifications, warranties, and guarantees, all stakeholders will be satisfied, including the owner developer, engineering firm, regulator, responsible party, and labor organization. Vapor mitigation systems are now Standard Operating Procedure on many redevelopments, schools, retail, commercial and residential complexes nationwide. 79

80 Questions Contact Amanda Petrocelli or Robert Carvalho with any further questions. Amanda Petrocelli Phone: ext. 261 Robert Carvalho Phone: ext. 229 Visit EAI on the web: Visit CETCO on the web: 80

GAS VAPOR MITIGATION SYSTEMS

LINING TECHNOLOGIES REMEDIATION TECHNOLOGIES DRILLING SYSTEMS BUILDING ENVELOPE CONTRACTING SERVICES GAS VAPOR MITIGATION SYSTEMS FOR PROTECTION AGAINST VAPOR INTRUSION Gas Vapor Barrier System High-Performance