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New Technology for Mapping DNAPL Contamination

Laser-induced fluorescence (LIF)

As reported in Groundwater Monitoring and Remediation (38(3):28-42), DyeLIF™ is a new version of laser-induced fluorescence (LIF) for high-resolution 3D mapping of NAPLs in the subsurface.   DyeLIF eliminates the requirement that the NAPL contains native fluorophores (such as those that occur in compounds like PAHs) and therefore can be used to detect chlorinated solvents and other nonfluorescing compounds.

NAPLs were previously undetectable with conventional LIF tools. With DyeLIF, an aqueous solution of water and nontoxic hydrophobic dye is continuously injected ahead of the sapphire detection window while the LIF probe is being advanced in the subsurface.  If soil containing NAPL is penetrated, the injected dye solvates into the NAPL within a few milliseconds, creating strong fluorescence that is transmitted via fiber-optic filaments to aboveground optical sensors. This paper describes a detailed field evaluation of the novel DyeLIF technology performed at a contaminated industrial site in Lowell, Mass., where chlorinated solvent DNAPL persists below the water table in sandy sediments..

The DyeLIF system was field tested at a Formerly Used Defense (FUD) facility in Massachusetts in Fall 2013 (Geoprobe® delivery) and again in March 2014 (CPT delivery). The primary field demonstration completed in 2013 included two components: one week of DyeLIF probing and a second week of follow-on soil coring using research-quality direct push (DP) soil coring methods in order to compare DyeLIF results to colorimetric dye shake tests and laboratory analysis.

Several performance objectives were established in the project demonstration work plan and all were met or exceeded. The performance objective for chemical analysis was 70% consistency between positive DyeLIF responses and samples when DNAPL saturations were greater than 5%. The demonstration results showed 100% consistency between chemical analysis and DyeLIF for saturations greater than 1.9% (35 of 35 samples), and 95% consistency for estimated saturations greater than 0.5% (40 of 42 samples).

ESTCP funded Project ER-201121 to demonstrate the DyeLIF technology.  Additional details on the technology can be found at the U.S. Department of Defence Strategic Environmental Research and Development Program (SERDP) and the U.S. Department of Defence Environmental Security Technology Certification Program (ESTCP) link at SERDP-ESTCP.

2D and 3D Conceptual Site Models of a Contaminated Property

Innovations in Pipeline Design: Leak-proof technology

By Dema Mamon, M.Sc.Pl, BES and John Nicholson, M.Sc., P.Eng.

In Canada, getting approval to construct an oil pipeline has become increasingly difficult.  Every oil pipeline incident that involves a leak and subsequent clean-up is widely covered in the media,  providing fuel for pipeline opponents that call an end to the construction of new pipelines.

Abacus Data Inc., an Ottawa-based research firm, has been tracking public opinion on the construction of new pipeline capacity and has found some interesting trends.  Since 2014, polling has shown that the negative view of building new oil pipelines has remained steady at 21 to 22% range.  However, there was a drop in the positive attitude amongst Canadians toward building new pipelines – from 58% in 2014 to 44% in 2017.  Over that three year span, a good proportion of Canadians who once viewed building new pipeline capacity with a positive attitude have shifted to a neutral view.  The neutral view on oil pipelines have grown from 20% in 2014 to 36% in 2017.

There can be many theories to explain the three year shift in public opinion on new oil pipelines.  One plausible theory is that oil spills from pipelines typically make headline news, thus leaving an impression in the minds of Canadians the perhaps pipelines are not as safe as the industry states.  Oil leaks from pipelines damage the environment, are costly to clean-up, and fuel public opinion that pipelines are not safe.

One way to eliminate the perception that building new oil pipelines is bad for the environment and shift public opinion in favour of such projects is to build pipelines that don’t leak.  However, is it even possible to build leak-proof pipelines?

Are Double-Walled Pipelines the Answer?

One logical idea for building leak-proof pipelines is for them to be double-walled.  The outer wall would serve as protection from external damage.  The technology does exist to construct double-walled pipelines and they are used in certain circumstances such as when there is a large temperature difference between the liquid in the pipe and the surrounding environment.

Double-walled pipelines are not considered the cure-all by some in the industry.  Those resistant to the use of double-walled pipelines note that in some instances, it may be more cost effective to protect pipelines from the potential of external damage by burying them or placing slabs over them in higher risk areas.  Furthermore, it can be more difficult to monitor a double-walled pipeline and an outer pipe interferes with the maintenance of the inner pipe.

At the University of Calgary, researchers believe their two-walled pipeline design and monitoring system is the solution to preventing spills.  Although double-walled pipelines have been around since the 1980’s, Thiago Valentin de Oliveira, an electrical and computer-engineering master’s student, and Martin Mintchev, an engineering professor, say that their design is superior.

The U of Calgary researchers designed and constructed their prototype to consist of a typical steel inner layer with either a steel or plastic outer layer.  There is an air gap between inner and outer pipeline contains the oil that leaks from the inner pipeline leak.  The real innovation developed by the U of Calgary is the segmentation of the inter-pipe space and the inclusion of a linear wireless network linking the segments.  With the segmentation, a leak of oil from the inner pipe enters the air gap between the two pipes and is contained in a section of pipe.  Wireless pressure sensors between the two walled layers detect the pressure build up and send an alert to the pipeline control staff.

 

If commercially implemented, the U of Calgary system would allow pipeline operators with the means of quickly shutting down the pipeline when a leak was detected into the outer pipeline and crews could be dispatched to make repairs.  The oil that leaked from the inner pipe would be contained in the air gap between the two pipes and be confined to one section of the pipeline.

The U of Calgary researchers estimate that their design would result in an additional 25% in the capital cost of building pipelines.  They believe this cost could be reduced if the outer pipeline material was composite materials or plastic.

Is Advanced Monitoring the Solution?

Also in Alberta, a Calgary-based firm, HiFi Engineering, recently announced that it has developed an innovative pipeline leak detection system.  Dubbed High-Fidelity Dynamic Sensing (HDS™), the monitoring system can spot the exact location of a leak in a pipeline within seconds of it occurring.  The system continuously monitors temperature, sonic and ultrasonic acoustics, and vibration and strain.  Any anomaly in the measurements results in an alert being sent to the pipeline company control room.

Hifi Engineering’s High Fidelity Dynamic Sensing (HDS) technology is being called the ‘ears of pipeline monitoring.’

The system works utilizing fiber optic cables that run the length of the pipeline.  A laser beam is sent down the length of the optic cable and sends signals back that provide a multitude of information to the pipeline control room.

TransCanada Pipelines Corporation has already installed the HiFi HDS™ monitoring system in sections of the Keystone XL oil pipeline that runs from Canada to the U.S.  Also, Enbridge employs the technology in its new northern Alberta pipeline.

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About the Authors

Dema is a graduate of York University’s Bachelor in Environmental Studies program (2008) and the University of Toronto’s Masters of Science in Planning Programme (2010). She is currently pursuing her Canada Green Building Council’s Leadership in Energy and Environmental Design’s Green Associate certification. Her research interests include environmental conservation, green infrastructure, and sustainability. She can be reached at dema.mamon@gmail.com.

John Nicholson is the editor of Hazmat Management Magazine.  He has over 25 years of experience in the environmental and cleantech sectors.  He is a registered professional engineer in the Province of Ontario and has a M.Sc. in environmental engineering.  His professional experience includes time at a large engineering consulting firm, a major Canadian law firm, and the Ontario Ministry of the Environment and Climate Change.

Advance Technology Camera spots hidden Oil Spills

As reported in the New Scientist, a new kind of polarising camera is available that can detect otherwise invisible oil sheens.

Like many oil imagers, the Pyxis camera sees the infrared radiation emitted by all objects.  That is important because there is often a temperature difference between oil and water.  However, if there isn’t one, thermal imagers don’t work.  So the Pyxis also detects differences between the way oil and water scatter light.  Thanks to this differing polarisation, it works not only when the oil and water are the same temperature – but also in pitch darkness.

Infrared polarimetry has been used in astronomy to help identify distant stellar objects. Polaris Sensor Technologies, based in Alabama, has modified the technology for a new use.

“The optical system and the physics behind it are very complex,” says David Chenault, President of Polaris Sensor Technologies.  “We started building infrared polarimeters several decades ago, but they were bulky and not capable of looking at dynamic scenes.” Only in the past few years did it become possible to significantly shrink the sensor – now roughly the size of a fist – and make it capable of imaging moving scenes. That is important for detecting oil on water.

The new camera can see spills invisible to the naked eye from 2 kilometres away.  Its size means it can be mounted on a small drone or other robot.

Doug Helton of the National Oceanic and Atmospheric Administration Emergency Response Division says these cameras could augment NOAA satellite networks, which detect and track suspected oil spills.  While they can spot even small spills, visual confirmation is crucial to rule out false positives. “Wind shadow may look like an oil slick,” he says.

Confirmation is usually done by people in a helicopter or plane, so that is where a drone-mounted camera could save a lot of time.

The camera can also spot and track oil washed up on beaches. Typically, this is a time-consuming task that must be done by people on the ground.

The sensor passed extensive tests with crude oil and diesel in different wave conditions at the massive Ohmsett test facility pool in New Jersey and at an actual spill off Santa Barbara, California, in 2015.  Russell Chipman at the University of Arizona says this is a significant development. “The costs of polarimeters are decreasing,” he says, and the miniaturisation and commercialisation of infrared polarimetric sensors means this technology can now be deployed widely to detect all kinds of oil slicks.

While Polaris is currently concentrating on oil detection, more applications for the camera are likely to be discovered when it goes into mass production, anticipated early next year.

 

Confirming the Chemical Identity

Philip Tackett, a certified HAZMAT responder and a Product Manager at FLIR, discusses its latest tool for chemical identification

 

By Philip Tackett

Civilian and military responders face scenarios ranging from intentional chemical attacks and accidental hazardous material (HAZMAT) releases to natural disasters and environmental monitoring or remediation efforts.  Responders step on-scene with a diverse toolkit – sometimes small and other times extensive.  It is critical to stay familiar with the equipment in the kit, because no single chemical detection tool can provide answers for every scenario.

Colorimetric test kits are one of the most commonly used technologies for quickly collecting presumptive information about a chemical.  They are used to determine if a threat is present and determine its chemical class.  This information is important, but knowing the exact identity of a chemical can inform a safer response.  True chemical identity can provide information to responders and law enforcement officials beyond the initial threat, and lead to further discoveries to further safeguard the public.

Griffin G510

While some detectors only indicate the presence of a chemical, others specifically detect hazards in the presence of a complex chemical background, like a gas chromatograph mass spectrometer (GC/MS).  GC/MS is an incredibly sensitive and highly specific tool commonly used in laboratory environments.  It can sense trace level chemicals other equipment can’t, while also providing the ability to positively identify the chemical.  But chemical emergencies don’t just happen in laboratories – they can happen anywhere.

Real-time chemical detection and identification in the field is critical to the Chemical, biological, radiological, nuclear, and explosives (CBRNE) defense or HAZMAT response mission.  Confirmatory chemical identification enables responders to mitigate a threat and protect people and the environment from harm.

The most challenging aspects of taking gold-standard technology like GC/MS into the field is survivability in harsh environments and ease of use.  Significant technological advancements have led to the development of the FLIR Griffin G510 person-portable GC/MS system.  Its lab-quality detection performance, simple-to-use interface, and rugged construction are ideal for high-consequence response missions.

Response missions take place in complex environments that the GC/MS must withstand.  The Griffin G510 is completely self-contained in a 36-pound device, including batteries, carrier gas, vacuum system, injector, and heated sample probe.  It is also the first IP65-rated portable GC/MS.  This means it’s dust-tight and spray-resistant, which adds flexibility to decontamination procedures.  There is no 40-pound external service module like other portable GC/MS systems and no 20-pound external pump under the bench like those seen in a laboratory.  Batteries last up to four hours and are hot swappable, should the mission extend longer than expected, which eliminates the need for a power generator.  The Griffin G510 is designed from the ground up to operate outside of the lab.

Griffin G510 syringe injection

Hazmat technicians will dive into using the features that deliver lab-quality analysis.  First on-scene operators will appreciate that they don’t need a Ph.D. to use it.  Basic operator training is completed in only two hours, while expert training can be completed in a single day.  The user interface truly sets it apart from other portable GC/MS systems.  It’s streamlined design and guided controls help the user select the mode of operation.  First responders must perform quickly and with limited dexterity when wearing required PPE.  They are responsible for sample and data collection, and in some cases, real-time decision making.  The G510 alerts the operator with visual alarm confirmation both on the handheld probe, as well as the on-board 9” touchscreen.  The large touchscreen can be operated by a responder while wearing full personal protective equipment (PPE).

Hazmat responders can use the Griffin G510 to analyze all phases of matter (solid, liquid, gas). Its integrated survey mode capability identifies vapor-phase chemical threats within seconds.  Its integrated split/splitless liquid injector enables responders to perform direct injection of organic liquids – an industry first.  This same injector also accepts other sampling tools, including solid-phase microextraction (SPME), off-the-shelf headspace analyzers, and the Prepless Sample Introduction (PSI) Probe.  The PSI-Probe directly accepts solid samples in their native form (such as soil and water-based materials).  The Griffin G510 reduces the burden of sample preparation for the operator and provides ultimate flexibility as the daily mission changes.

Hazardous environments demand the ultimate toolbox include confirmatory instrumentation like GC/MS. The Griffin G510 portable GC/MS redefines performance, ease of use, and value for the responder toolkit.

Griffin G510 – checking readout