An article entitled "Simultaneous Monitoring of Volatile Organic Contaminant Concentration and Controlling Factors for Vapor Intrusion Risk Evaluations—Two Select Cases" describes two unique deployments of innovative continuous monitoring. One of these cases involved a "mystery" site where more than 3 years of investigation using traditional sampling approaches could not resolve critical questions. Within a few days all remaining questions were answered.
Article: Machine Learning to Predict Groundwater Levels
An article by Solgi, Loaiciga and Kram describe a methods to predict groundwater levels with exceptional accuracy using machine learning. This will be incorporated into key web based software platforms to rapidly determine available water supplies.
Case Study Article Receives Top Citation Rank by Wiley Publishers
We were recently notified by Wiley Publishers that our case study article entitled "Automated Continuous Monitoring and Response to Toxic Subsurface Vapors Entering Overlying Buildings - Selected Observations, Implications and Considerations", became “a top cited article and generated immediate impact in the community”. We are honored that our colleagues are citing our efforts. Thank you everyone!
An article entitled "Vapor Intrusion Risk Evaluation Using Automated Continuous Chemical and Physical Parameter Monitoring" points out how continuous monitoring is being used to identify vapor intrusion (VI) "events", whereby subsurface vapors are advectively migrating into buildings. Consistent with EPA VI guidance regarding risk decision criteria, time-weighted average concentration calculation during these events can be used to most accurately estimate the reasonable maximum exposure (RME). This article demonstrates that traditional randomly timed sampling methods are not capable of meeting this RME criteria, and can yield widely ranging results and response recommendations, as they do not coincide with these VI events. The implications are profound for many reasons.
On March 17, 2020, a select group of vapor intrusion specialists presented a workshop entitled "EPA's 2020 Vapor Intrusion Workshop: Why You Should Monitor Indoor Radon, Differential Temperature, and Pressure During Chlorinated Vapor Intrusion Assessments". Dr. Kram presented two brief segments where he discussed correlations between continuous concentration monitoring and vapor intrusion controlling factors such as barometric pressure and differential pressure. Documenting these types of correlations will be critical for implementing the EPA's indicator, surrogate, tracer (IST) program.
Article: Automated Continuous Monitoring Observations
An article entitled "Automated Continuous Monitoring and Response to Toxic Subsurface Vapors Entering Overlying Buildings—Selected Observations, Implications and Considerations" is gaining praise for describing several cases where automated real-time continuous monitoring and response was employed to rapidly resolve key vapor intrusion challenges. The approach continues to garner the attention of private and agency practitioners tasked to quickly address risks and liabilities resulting from vapor intrusion exposures.
Dr. Kram and Dr. Hartman Webinar on Vapor Intrusion
Automated Real-Time Vapor Intrusion Monitoring and Response Gaining Momentum
Vapor intrusion challenges are global in scale. Unfortunately, traditional methods for assessment often result in incorrect conclusions, unresolved questions, the need for repeat field campaigns, delays in real property and Brownfields transactions, and unnecessary public exposures. Key factors have to do with the complex dynamic nature of vapor concentrations, preferential pathways, and natural events and anthropogenic activities that can result in undetected risks. In addition, traditional methods require weeks for a laboratory result. For acute risks posed by TCE, there is a need for immediate response (e.g., within hours or days). To address these challenges, Dr. Kram and his colleagues developed a laboratory grade analytical system capable of tracking dynamic concentration and other factors in real time from multiple locations simultaneously via a Cloud hosted dashboard. This has allowed clients to rapidly resolve unanswered questions and derive long-term solutions. Automated responses are also being implemented. A brief summary of selected projects has been posted.
Vapor Intrusion Technology Comparison Matrix
A new vapor intrusion characterization and response technology comparison matrix has been posted to point out similarities and differences between the various options available to consultants and their clients. Traditional time-integrated sampling approaches do not allow for dynamic concentration data patterns to be revealed, and as such, can lead to incorrect conclusions and an inability to determine cause-and-effect relationships. In addition, they require more time to process than the acute TCE exposure duration of concern, so liabilities and harmful exposures can result. In contrast, field analytical and automated options exist that can resolve the challenges posed by conventional methods. This comparison lists key objectives and rates the various options based on their ability to meet specific goals.
Vapor Intrusion Used as Key Criteria for NPL Listing
On September 13, 2018, the United States Environmental Protection Agency took the unprecedented step of adding a contaminated site to the Superfund National Priorities List (“NPL”) based solely on the risk to human health posed by indoor air vapor intrusion at the site. The newly designated site, which consists of the former Rockwell International Wheel & Trim facility and its surrounding 76 acres, is located in Grenada, Mississippi. EPA’s primary concern—and reason for listing the site—is the potential for airborne volatile organic compounds (“VOCs”) to enter the facility through cracks, joints, and other openings, resulting in contaminated indoor air. The potential for indoor air contamination appears to be of particular concern to EPA, given that nearly 400 individuals currently work within the facility.
Legal Victory for Monterey Coastkeeper as Court Rules Regulations for Ag Runoff Fall Short
Monterey Coastkeeper has successfully defended their position in California's Third District Court of Appeals. A September 18, 2018 decision affirms a previous ruling that the state's effort to regulate agriculturally derived water pollution on the Central Coast was too lenient. This could prove to be a ground-breaking decision, as it is anticipated to result in significant increases in monitoring and mitigation throughout California and beyond. Dr. Kram participated in some of the earlier deliberations related to this issue, and has advocated for use of proven and upcoming remote monitoring and response technology, while also exercising punitive restraint, particularly during the early phases of program development.
On August 24, Ohio EPA released new guidance that incorporates what many consider to be the most aggressive regulatory approach to addressing vapor intrusion risks in the US. Under the new guidance, Recommendations Regarding Response Action Levels and Timeframes for Common Contaminants of Concern at Vapor Intrusion Sites in Ohio, the Agency is for the first time demanding immediate action when contaminant levels exceed certain established “trigger” levels for trichloroethylene (TCE). The guidance has major implications for businesses, property owners, consultants and attorneys.
Dr. Kram Publishes Cost Comparison: Continuous Automated Vapor Intrusion Monitoring vs. Passive Sampling Approaches
Dr. Kram and distinguished colleagues (Dr. Blayne Hartman and Cliff Frescura) derived a cost comparison between continuous automated vapor intrusion monitoring and passive sampling approaches. The authors have gained considerable experience deploying continuous monitoring systems and have documented that continuous monitoring costs are competitive with currently accepted passive sampling approaches. Continuous monitoring also allows for immediate and automated response to acute TCE risks before exposures have exceeded a duration of concern.
Shell and Dole Settle Carson Carousel Suit for $120M
Shell Oil Co. and Dole Food Co. (parent firm for Barclay Hollander Corp.) will pay a $120 million good-faith settlement to vacate the personal injury class action lawsuit filed by about 1,500 Los Angeles area residents who allege that they were injured by waste oil buried in the ground. The class action settlement will alleviate any future judgments against the defendants. In addition, Shell and Dole will pay for cleanup as ordered by the Los Angeles Regional Water Quality Control Board.
Dr. Kram Publishes GWMR Guest Editorial on Vapor Intrusion Methodologies
Dr. Kram's Guest Op/Ed entitled "The Emperor's Old Clothes: An Inconvenient Truth About Currently Accepted Vapor Intrusion Assessment Methods" was published in the Fall 2015 issue of Ground Water Monitoring and Remediation (GWMR). Dr. Kram discusses concerns regarding the use of traditional methods for evaluation of vapor intrusion risks (particularly acute TCE and methane risks), rationale behind these concerns, prevailing claims regarding fate and transport that have yet to be thoroughly evaluated, and recommendations moving forward.
New Automated Vapor Intrusion Measurement and Acute Risk Mapping and Alerting Platform - VaporSafeTM
Hartman Environmental Geoscience (HEG) and Groundswell Technologies (GT) have partnered to deploy automated continuous vapor intrusion (VI) assessment, mapping and alerting services to overcome formidable shortcomings associated with the use of traditional methods when acute risks are dynamic. HEG has field-ruggedized and multiplexed a laboratory grade analytical instrument that has been modified to allow for automated continuous sampling and analysis of dynamic vapor concentration distributions and potential acute risks throughout a building. This system consists of a gas chromatograph with an ECD, and can measure extremely low levels (e.g., 1 ug/m3) of TCE and PCE from up to 30 locations with a single device. GT has developed software to automatically generate geospatial visualizations of the analytical results, manage the incoming data, and trigger automated alerts and responses. The data is available 24/7/365 from any browser-supported device (including smart phones and tablets). The approach alleviates VI management and exposure risks while significantly reducing uncertainties associated with questionable results, expediting response times, and by pinpointing exact locations where vapors are entering structures. The system is also ideal for confirming that mitigation systems are performing as specified. Using this new platform, HEG and GT have documented several cases where traditional approaches would have resulted in false positive and false negative conclusions.
EPA Releases Long Awaited Vapor Intrusion Guidance
EPA has released two new vapor intrusion (VI) guidance documents to help practitioners navigate the complexities associated with evaluating and mitigating sites suspected or documented to pose health risks to inhabitants. "Technical Guide for Assessing and Mitigating the Vapor Intrusion Pathway From Subsurface Sources to Indoor Air" is a comprehensive document that offers many key considerations and recommendations applicable to sites where volatile contaminants have been released to the subsurface. "Technical Guide for Addressing Petroleum Vapor Intrusion at Leaking Underground Storage Tank Sites" covers many similar concepts, but with a focus on volatile petroleum constituents and breakdown products. Both documents acknowledge that exposure and explosion risks are dynamic and describe factors that contribute to the spatial and temporal variability that must be considered when determining worst case risk scenarios.
Shell Settles Carson Carousel Suit
Shell Oil Co. will be allowed to pay a $90 million good-faith settlement to vacate the personal injury class action lawsuit filed by about 1,500 Los Angeles area residents who allege that they were injured by waste oil buried in the ground. However, the lawsuits against the neighborhood developer, Barclay Hollander Corp. and Dole Food Co., which is the current owner, will continue. The $90 million class action settlement, which has been approved by a California judge, will alleviate any future judgments against Shell made in the class action lawsuit against the developers. In addition, Shell will still pay for part of the cleanup as ordered by the Los Angeles Regional Water Quality Control Board.
Dr. Kram and Dr. Loaiciga Receive US Patent for Groundwater Sustainability Invention
Dr. Kram and Dr. Loaiciga (UCSB) received a US Patent entitled "Integrated Resource Monitoring System with Interactive Logic Control for Well Water Extraction". Their invention is designed to protect from groundwater basin overdraft, seawater intrusion and stream depletion by automatically determining maximum sustainable groundwater extraction rates. When unsustainable conditions arise, responsible parties can be notified or extraction rates can auto-adjust. Unlike traditional models used by most consultants and agencies, this system specifically addresses sustainable extraction rates at the local well and well network level without adding artificial constraints such as fixed boundary conditions and forced potentiometric surfaces that are simulated. In contrast, this empirically based system responds to live dynamic measurements of extraction rates and water levels, and includes a self-calibration component. The system can also be used by agencies tasked to evaluate and approve new well permits, as the platform predicts impacts of the proposed extractions. The timing is perfect for addressing new legislation to help California communities become more water sustainable.
Governor Brown Signs Historic Groundwater Legislation
Governor Edmund G. Brown, Jr. enacted legislation to help California communities become more water sustainable. Key components include requirements for at-risk basins to designate a "groundwater sustainability agency" and development and adoption of a "groundwater sustainability plan" within a few (5-7) years. For local agencies who do not comply, the State Water Resources Control Board may intervene and adopt and enforce their own plan for the basin.
Dr. Kram and Dr. Everett Receive 2014 ASTM Committee D18 Technical Editors Award
At the ASTM meetings in Toronto this past June, Dr. Mark Kram and Dr. Lorne Everett received the prestigious 2014 ASTM International Committee D18 Technical Editors Award for their work on the publication entitled "STP1570, Continuous Soil Gas Measurements: Worst Case Risk Parameters". The book represents a compilation of selected papers presented at the similarly named ASTM International Symposium held in January of 2013 in Jacksonville, FL, USA, which was co-Chaired by Drs. Kram and Everett. The symposium and publication were organized by ASTM leaders following Dr. Kram's documentation that soil vapor concentrations and risks can be extremely dynamic. Using continuous sensor based monitoring, dramatic changes in subsurface methane levels coincided with slight changes in barometric pressure. Implications are profound, as it calls into question traditional point-in-time sampling and monitoring methods employed in vapor intrusion investigations. It remains to be seen whether regulatory policies will fully endorse continuous monitoring. The symposium participants and authors of the papers in STP1570 are convinced that traditional monitoring approaches yield data that do not represent worst case risks.
EPA Region IX Releases New Short-Term TCE VI Policies; RPs Push Back
On July 9, 2014, USEPA Region IX released their TCE Interim Action Level Memorandum, and as expected, established Accelerated Response and Urgent Response action levels for TCE vapor inhalation exposures in commercial and residential settings. Unfortunately, EPA recommends use of time-integrated sampling approaches, which have been suspected of yielding non-representative results, as they do not accurately account for time-specific exposure concentrations, yield an average concentration over the sample collection duration (which can underestimate maximum exposure levels), and are typically deployed for limited durations. This is problematic, as exposure risks can exhibit dynamic and episodic patterns. Meanwhile, industry is challenging these revisions and claims that neither the Region nor EPA headquarters has formally adopted these changes.
Supreme Court Ruling Leaves Victims Without Recourse
On June 9, 2014, the Supreme Court ruled in CTS Corp v. Waldburger et al. that North Carolina’s statute of repose is not preempted by the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). As such, if contamination is discovered after the statute of repose has expired (which for North Carolina is 10 years), victims have no recourse. Many high level cases in the US are based on contaminant risks discovered many decades after contaminants were released. For ideas and options regarding how best to address this, contact our associates.
Dr. Kram Presents Webinar on Vapor Intrusion
Dr. Kram was invited by the Midwest GeoSciences Group to give an international webinar entitled "Vapor Intrusion Challenges, Technologies, and Risk Management Solutions: Addressing Impacts of New Revelations and Policies." The presentation was well-received and can be viewed on-demand through their portal.
New Publication Suggests High Probability of False Negative Vapor Intrusion Results Using Traditional Methods
The most comprehensive vapor intrusion study to-date ("Temporal Variability of Indoor Air Concentrations under Natural Conditions in a House Overlying a Dilute Chlorinated Solvent Groundwater Plume"; Holton et al., 2013) concluded that traditional vapor intrusion characterization methods can result in incorrect conclusions and decisions due to the dynamic nature of risks. This Department of Defense sponsored effort could have a profound impact on future vapor intrusion assessment and response efforts. Furthermore, this could result in reopening of sites deemed low risk based on earlier assessment efforts.
ASTM International Releases New Book on Continuous Monitoring for Vapor Intrusion Assessment
In response to Dr. Kram's findings regarding dynamic vapor intrusion potential, ASTM International organized a special symposium, invited Dr. Kram to serve as co-Chair, and released a new book entitled "Continuous Soil Gas Measurements: Worst Case Risk Parameters" (Eds. Everett and Kram). The book includes new methods for most effectively addressing vapor intrusion potential as well as recommendations for regulatory agencies and policies.
Dynamic Vapor Intrusion Risks Documented
This seminal article ("Dynamic Subsurface Explosive Vapor Concentrations: Observations and Implications"; Kram et al., 2011) describes how Dr. Kram used continuous sensor based real-time automated monitoring and data processing and visualization to document that subsurface vapor concentrations can fluctuate widely over short periods, and as such, vapor intrusion risks can be dynamic. The implications are profound, in that these findings suggest that in order to determine worst case risks, practitioners should consider using high frequency or continuous monitoring approaches.
Dr. Kram Delivers Keynote MIT Presentation on the Use of Technology to Solve Water Supply Challenges
Days before Governor Brown declared a state of emergency based on California's drought, Dr. Kram deliver a keynote presentation at the MIT Forum to describe how technological advances developed over the past few years have the potential to solve the current water supply crisis. Success or failure will greatly depend upon how rapidly water agencies can adopt some or all of the recommendations discussed. The clip below features Dr. Kram's presentation as well as presentations from Russell McGlothlin (Attorney for Brownstein, Hyatt, Farber and Shreck) and John Krist (CEO of the Ventura County Farm Bureau) and a detailed panel discussion.