Toronto

Treatment of Recalcitrant Organics Using Solar Photocatalysis

Conventionally, the treatment of recalcitrant dissolved organics requires significant chemical and electrical inputs and capital-intensive process equipment. To this end H2nanO has developed SolarPass, a passive oxidative treatment technology consisting of a system of buoyant photocatalyst composites that provides off-grid, high strength oxidative treatment of organics without the need for chemical or electrical inputs. H2nanO’s photocatalyst technology generates free radicals from the treatment effluent itself, including hydroxyl and superoxide, upon exposure to naturally occurring solar or artificial ultraviolet (UV) light. As the photocatalyst media is not consumed, they may be collected for reuse once treatment is complete using low-energyflotation or a similar process. SolarPass can be continuously operated without operator intervention, gas handling, or adsorbent regeneration/disposal. Further, for the treatment of volatiles and semi-volatiles SolarPass can act as a floating reactive barrier, mitigating volatile emissions while simultaneously providing sunlight-driven oxidative treatment. Currently,H2nanO’s SolarPass technology has been identified as a solution for the treatment of complexlong-chain organics within the Canadian Oil Sands, an issue which is insufficiently addressed by conventional treatment technologies. This presentation will further discuss H2nanO’s treatment technology and highlight treatment case studies, at various stages of development, for recalcitrant organics including polycyclic aromatic hydrocarbons (PAHs), petroleum hydrocarbons, 1,4-dioxane, and BTEX compounds

In Situ Biogeochemical Process for the Treatment of Chlorinated Organics and Metals

Background

For over two decades, biotic (enhanced reductive dechlorination; ERD) and abiotic (in situchemical reduction; ISCR) processes have been applied to degrade chlorinated volatile organiccompounds (CVOCs) in situ. Recently, biogeochemical reduction (BGCR), a process whichcombines biological and chemical processes, has been combined with ERD and ISCR to providean additional mechanism to more aggressively degrade CVOCs and to sequester metals.During ERD and ISCR, highly reducing conditions are generated which are favorable to thereduction of ferric iron (Fe3+) to ferrous (Fe2+) and sulfate (SO4) to sulfide (S-). If present, theferrous and sulfide rapidly combine to produce iron-sulfide minerals such as mackinawite (FeS),and pyrite (FeS2). These biologically generated minerals have been demonstrated to abioticallydegrade CVOCs on contact by the β elimination pathway. This pathway minimizes thegeneration of toxic degradation products thereby substantially reducing the clean-up time. Inaddition to forming reactive minerals, the sulfide will precipitate on zero valent iron (ZVI) ifpresent. This sulfidation of ZVI has been demonstrated to substantially enhance ZVI reactivity.

Approach

Bench tests, field pilot studies and full-scale treatment have been conducted to evaluate the effectiveness two BGCR enhancing reagents (GeoformTM Extended Release and GeoformTM Soluble) for treatment of CVOCs and sequestration of toxic metals. These reagents have been applied at sites with distinct hydrogeologic and geochemical conditions, and contaminant concentrations. Innovative analytical techniques were used to confirm the generation of the formation and characterize the type of minerals formed.

Results

The bench tests demonstrated that BGCR enhancement significantly increased the reactivity of the ISCR reagent. The field tests demonstrated that the biologically mediated establishment of highly reducing conditions resulted in the reduction of the supplied sulfate to sulfide. Analysis confirmed that the sulfide combined with the supplied ferrous resulting in the rapid generation of a combination of reactive iron sulfide minerals. The combination of these technologies resulted in the rapid destruction of CVOCs and sequestration of toxic metals.This presentation will describe the synergistic changes in geochemical conditions which occur during BGCR enhanced ERD and ISCR. The unique methods for identifying these newly formed minerals will be described, and the results of full-scale application of BGCR enhanced ERD andISCR for treatment of CVOCs and metals will be presented.

Leveraging Your CSM to Develop Successful Bedrock Remediation Approaches - Concepts & Case Studies

Fractured bedrock sites present unique characterization and remediation challenges.Developing an accurate conceptual site model (CSM) is a critical first step in the remediationprocess. Some of the key aspects of CSM development at bedrock sites include identifying therock type, delineating the source mass, characterizing the fracture network, andunderstanding the groundwater flow regime. For in situ remediation at bedrock sites, thetreatment technology and/or amendment delivery method require careful consideration ofthese CSM components.

This presentation will highlight the key features of various fractured bedrock types and howthese influence remedy selection, design and implementation. Several key considerationsinclude: i) the influence of bedrock structure on migration of contaminants and amendments;ii) the role of bedrock porosity in terms of mass storage and access; iii) the potential formobilization or altered flowpaths during remedy implementation; and iv) the advantages ofspecific remedial approaches in treated mass stored in the bedrock matrix.

We will present site examples and a case study that demonstrate how well-developed CSMscan be leveraged to implement successful remediation approaches at complex bedrock sites.The detailed case study is a site in Ontario where a tetrachloroethene (PCE) source area andplume in weathered shale has been investigated and treated using an anaerobicbioremediation approach. At this site, many of the considerations noted above wereimportant considerations in designing and implementing the remedy. The potential forrebound related to back diffusion and alteration of flow paths during the remedyimplementation also played a role in how the remedial program was designed andimplemented.

Curtain Walls, Sub-slab Depressurization, and Chemical Barriers – Building a CVOC Prison

A case study on a confidential oil company site where traditional remediation would have cost over $20M; instead, a strategy involving Risk Assessment and the implementation of a wide variety of RMMs was designed and executed to support the filing of an RSC for <$5M.

Environmental Financing – What I’ve Seen in 23 Years at the Bank & Predictions for the Future

Having soil or groundwater contamination on a site was once the kiss of death for getting a property financed. It did not matter what the contaminant was, where it was or how extensive it was, banks had no interest and maintained that position for years. They were oblivious to the fact that they already had 100’s of properties with contamination issues in their lending portfolio.So long as the borrower continued to make the payments on the loan, the bank was happy to be blissfully unaware. It has changed since that time and some banks will finance a site that they know is contaminated for the right client. By that, I am referring to those that manage the contamination appropriately (preferably through active remediation), they have a realistic remediation plan and they have a long term quality tenant. These type of tenants can always make the rent so that the bank never has to take the site back. Risk assessments help but they are not the panacea that some clients and consultants think they are, and they are not suitable for all sites. More than few client have gone to the expense of getting a risk assessment done to only find out the bank has no interest. Not because of the quality of the risk assessment but because the quality of the asset.

Case Studies – Using Environmental Insurance to Facilitate Brownfield Development

Across Canada, there is an increasing need to build infrastructure and residential communities on urban and industrial lands. Learn how environmental insurance can be used as a tool to reduce the liability of acquiring, building on, and repurposing environmentally challenging properties. Using case studies, attendees will learn strategies to minimize environmental liabilities and achieve better outcomes.

Excess Soils – What’s Next?

N/A

A Developer’s Perspective – All the Pieces of the Puzzle

A holistic overview conversation of everything the developer needs to consider regarding soils and groundwater contamination, and how it ties into the total proforma and construction budget/schedule/permit planning process. 3 stagesto touch on:

1. Acquisition – due diligence review – do we want to take this on? Is it worth it? How bad is it? What is the density we can get approved for/build at what sales value to offset remediation work required?

2. Development
• Site Plan Review/Pre-Approval Conditions
• RSC/RA program – need RSC for full permit – need Site Plan Approval to get a permit, but can’t get a permit without an RSC, can’t get RSC without remediating, can’t remediate without excavating, can’t excavate without a permit…
o Full Permits vs Conditional Permits vs Standalone Permits – what to apply for when • CPU – what are the conditions to adhere to? How to lock this down into a trade contract?
• Budget – how to prepare the proforma 3 yearsin advance
• Bathtubbing foundations – how much does this add to the budget? Costs review of bathtubbing vs discharging if the infrastructure is even available to handle the amount?
• Soils remediation/delineation – Soils Management Plan – Excess Soils Reg – what to believe/how to prepare?
• Groundwaterremediation – TW Discharge – Sani or Storm – filtration and costs – what is the best and worst case scenario?
o Remember when we used to send a 1 page fax for construction discharge?!
o Preparing a redundant collection system IN CASE any groundwater gets through?!
o Any long term filtration required – what will pass on to the future condo board?

3. Construction
• CMP – logistics of what goes where o Space for waterfiltration units o Space for stock pile? o How are you excavating/bring trucksin and out o How are you stacking construction processes – i.e., what all can be done at the same time to maximize the efficiency of the schedule
• Construction schedule – what can start when on what type of permit? How to prepare schedule and proposed costs years in advance before you dig? Contingency plan upon contingency plan. o Tarion First Occupancy Dates and Outside Occupancy Dates prep Wrap Up and Conclusion

PFAS in Canada: A Legal Perspective on the “Forever Chemicals” – Laws, Guidelines, and Practical Considerations

Federal, provincial and territorial governments across Canada are considering how to address per- and poly-fluoroalkyl substances (PFAS). Canada and our provinces and territories now realize the potential toxicity and persistence of PFAS in the environment, but struggle to find ways to regulate and address PFAS, due to complexities involved in detecting, managing and remediating PFAS.

Jacquelyn Stevens and Matthew Gardner will:
• Provide a cross-country review of measures the federal, provincial and territorial governments are taking to address PFAS in the environment
• Consider whether and how PFAS are being addressed in environmental investigations, clean ups, and land transactions, and
• Provide considerations for environmental consultants and their clients when dealing with PFAS.

PFAS in Canada: A Legal Perspective on the “Forever Chemicals” – Laws, Guidelines, and Practical Considerations

Federal, provincial and territorial governments across Canada are considering how to address per- and poly-fluoroalkyl substances (PFAS). Canada and our provinces and territories now realize the potential toxicity and persistence of PFAS in the environment, but struggle to find ways to regulate and address PFAS, due to complexities involved in detecting, managing and remediating PFAS.

Jacquelyn Stevens and Matthew Gardner will:
• Provide a cross-country review of measures the federal, provincial and territorial governments are taking to address PFAS in the environment
• Consider whether and how PFAS are being addressed in environmental investigations, clean ups, and land transactions, and
• Provide considerations for environmental consultants and their clients when dealing with PFAS.