Alaska Department of Environmental Conservation (ADEC) secondary containment requirements for aboveground oil storage tanks (18 AAC 75.

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3 Valdez Marine Terminal Tank Secondary Containment System Catalytically Blown Asphalt (CBA) Liner Integrity Review and Testing Options Phase I Initial Assessment August 2012 The following summarizes initial research completed on the Catalytically Blown Asphalt (CBA) liners installed as part of the Valdez Marine Terminal (VMT) Secondary Containment System. This research includes an initial assessment of the type and suitability of a CBA liner for use as a secondary containment liner in a petroleum storage tank farm and options for permeability testing. CBA Liner Effectiveness A CBA liner is installed under all Crude Oil Storage Tanks and Ballast Water Treatment Storage Tanks. 1 The CBA liner is located below grade and serves as the base of the containment system. The walls of the Crude Oil Storage Tank Secondary Containment System are made of soil covered by geomembrane liner and concrete; the CBA is attached to the geomembrane or concrete at the base of the wall. The walls of the Ballast Water Treatment Storage Tanks Secondary Containment System are made of soil covered by geomembrane liner and exposed bedrock; the CBA is attached to the geomembrane liner or exposed bedrock at the base of the wall. Alaska Department of Environmental Conservation (ADEC) secondary containment requirements for aboveground oil storage tanks (18 AAC ) require: Onshore aboveground oil storage tanks must be located within a secondary containment area that has the capacity to hold the volume of the largest tank within the containment area, plus enough additional capacity to allow for local precipitation. Minimum secondary containment system requirements include berms, dikes, or retaining walls that are constructed to prevent the release of spilled oil from within the containment area; and with the exception of the area under a tank, components constructed of, or lined with, materials that are adequately resistant to damage by the products stored to maintain sufficient impermeability; resistant to damage from prevailing weather conditions; sufficiently impermeable; 2 and resistant to operational damage. 1 Valdez Marine Terminal C-Plan, Table 2-4, Tankage and Dike Containment Information, CP-35-2, Fifth Edition, Revision 2, February 24, Installations placed into service after May 14, 1992 must meet additional requirements including meeting an impermeable standard, rather than sufficiently impermeable. VMT Tank Secondary Containment System CBA Liner Integrity Page 1

4 Therefore, evaluation of CBA liner effectiveness should include an assessment of whether the CBA liner is: 1. Adequately resistant to damage by the products stored to maintain sufficient impermeability; 2. Sufficiently impermeable; 3. Resistant to damage from prevailing weather conditions; and 4. Resistant to operational damage. Is the CBA Liner Resistant to Damage from Petroleum Products? A 1998 report prepared by Golder Associates for ADEC 3 recommends against using asphalt liners in Alaska: Caution should be used in considering the acceptability of an asphalt or coal tar liner for secondary containment system applications in Alaska for two reasons. First, although coal tar is reportedly more fuel resistant than asphalt, asphalt is known to be adversely affected by hydrocarbon compounds, and the impacts of chemical degradation on the permeability of either substance should be carefully considered. Second both compounds are susceptible to cracking at temperatures common the Arctic environments [emphasis added]. The Golder report was prepared several years after the VMT CBA liner was installed. A more recent 2008 New York State (NYS) Guideline for Inspecting and Certifying Secondary Containment Systems of Aboveground Petroleum Storage Tanks at Major Oil Storage Facilities does not recommend asphalt liners under tanks that store petroleum. NYS concludes: 4 An asphalt liner by itself is not an acceptable secondary containment system because it is not chemically compatible with petroleum. However, NYS notes that it may be possible to use asphalt if the asphalt is coupled with a petroleum resistant sealant or an additional liner system to protect the asphalt from contact with petroleum. NYS requires that any asphalt liner coated with a chemically resistant sealant be tested prior to use to verify the liner system is effective in containing petroleum. PWSRCAC s contractor made a public information request to both the Alaska Department of Environmental Conservation (ADEC) and Alaska Department of Natural Resources (ADNR) State Pipeline Coordinators Office (SPCO) to obtain information on the original design basis and installation of the CBA liner to determine what type, if any, chemically resistant sealant was used to protect the asphalt liner from petroleum 3 Golder Associates, Final Report to State of Alaska Department of Environmental Conservation Division of Spill Prevention and Response, Technical Review of Secondary Containment System Technology for Alaska, May 1, New York State, DER-17: Guidelines for Inspecting and Certifying Secondary Containment Systems of Aboveground Petroleum Storage Tanks at Major Oil Storage Facilities, VMT Tank Secondary Containment System CBA Liner Integrity Page 2

5 damage. More information is needed to ascertain whether the CBA liner was initially installed over 36 years ago with a petroleum resistant sealant, and if so, whether that sealant remains effective today. Thus far, records obtained and reviewed from ADEC and SPCO have not confirmed the application of any chemically resistant sealant. A further inquiry to APSC may indicate whether a chemically resistant sealant was applied to the liner when the liner was initially installed. If a sealant was applied, further inquiry should be made as to the manufacturer s name and the manufacturer s recommended operating life for that sealant in cold weather conditions. PWSRCAC and its consultant have only recently received and begun reviewing historical SPCO and ADEC public record data collected on the CBA liner. However, preliminary review of those records shows that APSC has previously conducted CBA chemical resistance testing in the early 1990 s and determined at that time that hydrocarbons damaged the CBA liner when in contact for more than 90 days. A March 1993 letter from APSC to ADEC reported CBA chemical resistance test results showing that after 94 days and 22 hours, a CBA sample from the Tank 11 and 12 containment areas sustained damage after contact with crude oil and crude oil began to leak through the CBA test sample: The CBA was completely softened by the crude oil in the form of a paste like material. The softened materials had signs of leakage... 5 While some other CBA liner samples tested in the same 1993 tests series did not result in complete leak through after the day test period, significant chemical damage and liner deterioration were measured in each test sample. The 1993 tests confirm that in areas where hydrocarbon spills above and below the CBA have occurred, and where hydrocarbons have been in contact with hydrocarbons for more than 90 days such as tank farm contaminated sites where hydrocarbon persists today, the liner integrity is likely to be compromised. In June 2012, Harvey Consulting, LLC provided a report to PWSRCAC summarizing the VMT Contaminated Sites history. 6 This report summarizes where hydrocarbons have been spilled at the VMT in the past, where spills may have damaged the secondary containment liners, and where hydrocarbons persist today that may continue to deteriorate the liner or present ongoing environmental impacts. Harvey Consulting, LLC s (HCLLC s) report was provided to APSC on July 27, 2012 for review and comment. To date, no input has been received from APSC. A copy of this report is attached for reference. HCLLC s report to PWSRCAC was based on a review of ADEC s Contaminated Sites Database Records. HCLLC recommended additional materials be obtained from APSC on each contaminated site where petroleum contaminated soil and groundwater below the CBA liner. Those areas of contamination are expected to pose a higher risk of CBA liner damage, and those sites be high priority testing locations for Golder Associates liner integrity testing. 5 APSC letter to ADEC, March 23, 1993 transmitting CBA liner test results, Letter No G. 6 Harvey Consulting, LLC, Status of Contaminated Sites at Valdez Marine Terminal, Report to PWSRCAC, June 13, VMT Tank Secondary Containment System CBA Liner Integrity Page 3

6 Based on ADEC s data, it appears there were several instances where the CBA liner was ineffective in containing petroleum as hydrocarbons spilled in secondary containment leaked through the liner into soils below the CBA. This indicates areas where the CBA liner may be permeable and not working as effective containment. Does the CBA Liner Meet ADEC s Sufficiently Impermeable Standard? ADEC defines sufficiently impermeable at 18 AAC (124): Sufficiently impermeable means, for a secondary containment system, that its design and construction has the impermeability necessary to protect groundwater from contamination and to contain a discharge or release until it can be detected and cleaned up; for design purposes for a new installation, sufficiently impermeable means using a layer of natural or manufactured material of sufficient thickness, density, and composition to produce a maximum permeability for the substance being contained of 1 x 10-6 cm per second at a maximum anticipated hydrostatic pressure, unless the department determines that an alternate design standard protects groundwater from contamination and contains a discharge or release until detection and cleanup[emphasis added]. Asphalt more typically has a permeability of 1 x 10-4 cm per second which does not meet ADEC s 1 x 10-6 cm per second standard. However, sealant materials sprayed over the asphalt could further reduce permeability and may possibly reduce the permeability to ADEC s standard, depending on the type of sealant used, if any. As indicated above, information is needed to verify whether sealants were used, and if so, the effectiveness of those sealants today. Additional information has been requested from ADEC and ADNR on the CBA installation specifications to determine a more precise permeability rating for the CBA liner. Additional information is requested from APSC on whether sealants were applied and the lifecycle of those sealants as further explained above. CBA Liner Testing Permeability of the CBA liner could be evaluated using a combination of laboratory and field tests. CBA permeability could be tested in a lab using the ASTM D-5084 flexible wall permeameter test. 7 Representative samples of the liner could be obtained from secondary containment areas at the VMT where tanks have been taken out of service. For example, West Tank Farm Crude Oil Storage Tanks 17 and 18 have been taken out of service, and may provide an opportunity to excavate the CBA liner to obtain samples for laboratory testing. CBA chemical resistance 8 should be tested to verify the liner s current condition. This could be accomplished by using EPA Method 9090A 9 or ASTM D The EPA test 7 The ASTM D-5084, Standard Test Methods for Measurement of Hydraulic Conductivity of Saturated Porous Materials Using a Flexible Wall Permeameter. 8 Chemical resistance to petroleum products is the ability of the material to retain its physical strength and chemical barrier properties during and after direct contact with petroleum products. VMT Tank Secondary Containment System CBA Liner Integrity Page 4

7 method examines chemical resistance by immersing the liner material in petroleum for a period of 120 days. Tests can be conducted initially when a liner is installed and periodically thereafter to examine chemical resistance degradation over time. Field test methods could be considered including: borehole testing, flood testing, infiltrometer, double tube test methods, air entry permeameter testing, or chemical tracer testing. The Golder Associates report notes that visual inspection of a secondary containment system can indicate gross problems at the surface but will not provide information on the condition of a buried liner. Golder also recommends a combination of laboratory testing (flexible wall permeameter) and field testing (e.g., infiltration tests). Golder recommends that a statistically significant section of the liner be tested to establish confidence limits in the overall integrity of the system. NYS requires permeability testing once every five years for asphalt liners. Additional information has been requested from ADEC and ADNR on whether the CBA liner permeability was tested initially or subsequently during the liner life. Is the CBA Liner Resistant to Damage from Prevailing Weather and Operational Conditions? The VMT is located in Valdez, Alaska, a sub-arctic location. Ambient temperature commonly ranges from 0 0 F to 70 0 F. Soils freeze in winter and the CBA liner would be subject to freeze thaw cycles. Asphalt in a sub-arctic location would be prone to frost heaving and cracking. Additional information has been requested from ADEC and ADNR on CBA liner damage reported by APSC. Follow up to Phase I Initial Assessment A follow up to this Phase I Initial Assessment is planned. This follow up will include review of documents provided by ADEC and SPCO Preliminary Recommendations The following preliminary recommendations are offered as a result of this initial review. 1. Additional information is needed to verify the CBA design and installation. Public records requests were submitted to both ADEC and ADNR-SPCO, and these records will be reviewed in the near future. 2. Asphalt liners are not typically acceptable secondary containment systems for petroleum storage because asphalt is not compatible with petroleum. Therefore, it is important to determine if the CBA liner was treated with a petroleum resistant sealant when originally installed, and to determine if that sealant was tested for 9 EPA Method 9090A Compatibility Test for Wastes and Membrane Liners 10 ASTM D-5747, Standard Practice for Tests to Evaluate the Chemical Resistance of Geomembranes to Liquids. VMT Tank Secondary Containment System CBA Liner Integrity Page 5

8 chemical compatibility with the crude oil stored at the VMT. CBA chemical resistance may be tested using EPA Method 9090A or ASTM D Liners made of asphalt do not typically meet ADEC s sufficiently impermeable standard of 1 x 10-6 cm per second upon initial installation (more typically asphalt has a permeability of 1 x 10-4 cm per second, unless treated with additional sealants.) Therefore, permeability testing should be conducted in both the lab and field to examine liner permeability, and additional information should be obtained on sealants used. 4. Representative samples of the liner could be obtained from the West Tank Farm Crude Oil Storage Tanks 17 and 18 liner and permeability could be tested in a lab using the ASTM D-5084 flexible wall permeameter test. 5. Field test methods could be considered including: borehole testing, flood testing, infiltrometer, double tube test methods, air entry permeameter testing, or chemical tracer testing. VMT Tank Secondary Containment System CBA Liner Integrity Page 6