Who, What, When, Where & Why: Environmental Forensics

 

Questions regarding environmental forensics will come up at some level in almost every environmental project.

Cross Section Plume Map - Environmental Forensics
Site Conceptual Model – Cross Section of a Plume Map

This can range from drawing conclusions about a release from a UST system to sophisticated analysis of large environmental datasets collected specifically to identify contributions from multiple sources. The purpose of forensic interpretation is to tell a story. The story becomes most interesting when some or all responsibility shifts from one party to another. In many ways, this is a natural extension of developing a site conceptual model (SCM), and much of the data required for telling the story is collected as part of most primary environmental investigations. Do you need forensic data interpretation or interpretation of forensic data?

To get the most value for your dollars spent, it might be helpful to think of forensic techniques as a specialized way in which environmental data is evaluated rather than as a series of analytical techniques. Commonly collected data can have significant forensic implications, boring logs, slug tests, GC chromatograms and tentatively identified compounds (TICs) all have a story to tell. Prior to investing in the collection of dedicated forensic data, a good consultant will fully understand what answers you need and evaluate how close you are to those answers using data you already have. It may be, for example, that the data required to delineate and characterize the basic fate and transport of a chlorinated compound in groundwater, for regulatory purposes, is also sufficient to constrain the potential release date with the required precision. Or, the presence or absence of various gasoline oxygenates in a BTEX plume may be enough to identify the decade in which the release occurred.

 

 

A number of specialized analytical techniques can provide specific data useful for environmental forensics.

Chromatogram - Environmental Forensics
TPH Chromatogram

Only after reviewing existing data in light of the SCM can you start looking at the analytical techniques people usually associate with environmental forensics. The most basic may be petroleum fingerprinting, looking at the composition of LNAPL or petroleum in soil or water to identify the type of product present and degree of weathering. Like everything else in life, this can be done quick and inexpensive with moderate precision or slower and at greater cost for greater precision and defensibility. There are no foolproof analytical methods to date petroleum releases. However, the Christensen and Larsen (1993) method is often used to estimate the date of diesel/#2 fuel oil releases. This method is based on observed changes in the ratio of compounds over time due to biodegradation. While used with success in many cases, the further your site conditions are from those on which the method is based, the greater the caution should be exercised in interpreting results.

 

Moving beyond petroleum, a wide range of forensic techniques are available for different circumstances with an equally wider range in cost. With the right circumstances, specific tools like PCB congener analysis, stable isotope measurements, extended PAH analysis or sediment and groundwater age dating can provide key information to distinguish multiple sources or refine the understanding of contaminant fate and transport. As always, there is a tradeoff between the cost of sample collection and analysis and the need to document results with sufficient certainty to stand up to hostile scrutiny.

 

 

Leveraging existing data can ensure your environmental forensic efforts get you the answers you need.

You hope that you know (and like) what results you get from a forensic investigation. But even starting with a well-developed SCM, expect some surprises when the analysis and data evaluation are performed. The real life messiness of even the best environmental data is, on its own, a good reason to develop specific and realistic goals for a forensic evaluation before data collection. Developing those goals is easier when you are making the best use of the data you already have.

 

 

 

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Identify Your Trusted Sources of Information for a Hurricane Event – Hurricane Preparedness Week

SuperCell - Hurricane Preparedness Week - Trusted Sources of Information

Take simple steps to keep you alerted.

 

Staying aware of developing weather is critical to taking timely action for the safety of personnel and property. Tracking weather may not be high on your list of priorities during a busy workday, so take the time now to make sure that information will come to you when you need it.

 

Text Message Alert - Hurricane Preparedness Week - Trusted Sources of Information
Get emergency alerts sent directly to your phone.

Be sure to activate emergency alerts if available on your phone.

Every phone is different, so there isn’t one simple way to turn on alerts. Refer to the phone’s user manual or use the internet to search how to allow emergency alerts to be sent to your phone.

 

Consider getting a NOAA radio and programming it to receive alarms for your county.

NOAA radios are available online or in many stores. Learn more about NOAA weather radio at: http://www.nws.noaa.gov/nwr/

 

Sign up for text and email alerts.

A number of third party services allow you to subscribe to National Weather Service alerts and warnings by email and text message, so consider using the following link to sign up for a service: http://www.weather.gov/subscribe

You can also sign up for alerts based on USGS stream gauge data, a good idea if you have a site vulnerable to inland flooding:  http://water.usgs.gov/wateralert/

 

 

 

For additional sources, check out:

http://www.nws.noaa.gov/com/weatherreadynation/news/160404_hurricane_info.html

Bookmark the links most relevant to you so you can find them easily the next time bad weather threatens.

 

 

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Strengthen Your Business – Hurricane Preparedness Week

Strengthen Your Business - Hurricane Preparedness Week

NOAA mentions the importance of strengthening your home if you plan to ride out a storm, but a business owner needs to remember to prepare a second abode for bad weather: the workplace. It’s important to make sure your building is strong enough to hold up against a natural disaster. Vulnerable businesses and other sites can be retrofitted to be less vulnerable to hurricane damage in similar ways to homes.  An important and relatively inexpensive measure is to elevate critical equipment such as utilities or IT infrastructure above projected flood levels. In highly vulnerable or especially critical structures, installation of flood barriers may be a good investment now to save you in the future.

 

Tank - Strengthen Your Business - Hurricane Preparedness WeekOne hazard often unrecognized in both homes and businesses is the threat from hazardous or flammable materials stored in areas that could flood, most commonly stored heating fuel. Above-ground storage tanks (ASTs), propane tanks of all sizes and other small-scale chemical stores are often lost in flooding events. Even underground storage tanks (USTs) can be vulnerable to buoyancy induced damage or water infiltration during flood events. However, if planned for ahead of time, it is possible to anchor tanks and other storage vessels with cables or tie downs and move small vessels to secure storage areas so they don’t float away.

 

 

For more ideas on how to strengthen your home or business against a hurricane, visit:

http://www.flash.org/peril_hurricanes.php

 

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Developing an Evacuation Plan – Hurricane Preparedness Week

Hurricane - Evacuation Plan - Hurricane Preparedness Week

Plan out where everyone and everything must go.

 

Historically, industry has been concentrated along or near waterways. As a result, many businesses handling hazardous materials as well as many brownfield sites are vulnerable to flooding. With hurricane season just around the corner, those with businesses or homes in flood and storm surge prone areas need to be very aware of their risks. Everyone must have a plan to evacuate safely when instructed to do so.

Safety of employees and others is a high priority, but a business owner may also benefit from planning a way to safely evacuate equipment or supplies from risky areas ahead of time. Telling people to safely head home is one thing, but getting heavy equipment relocated can be much more difficult. Planning the transportation of equipment and deciding where it will be securely stored is best determined well in advance. Five hours to landfall is not the time to decide how and where to move that expensive trailer. Think about your evacuation needs now and plan accordingly to save time, money and your business from more damage than need occur.

 

For more information on developing an evacuation plan or to see if your business or home resides in a storm surge prone area, check out NOAA’s Hurricane Preparedness Week site:

http://www.nws.noaa.gov/com/weatherreadynation/news/160404_hurricane_evacuation.html

 

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Determine Your Risk – Hurricane Preparedness Week

 

Every business should be prepared.

As NOAA notes, hurricanes are not just a coastal hazard; inland flooding is a serious issue that can cause severe damage and is known to be the most common cause of hurricane-related deaths. Hurricanes, flooding, strong winds and resulting power outages can reach far inland and hit businesses that may not have anticipated being affected by the storm. For example, businesses have reported an increasing number of hazardous material and petroleum releases caused by hurricanes; about 3% of these occur in inland states with many more in inland areas of coastal states.

 

Increased Hurricane Activity - Determine Your Risk - Hurricane Preparedness Week

 

The good news is that it’s never been quicker or easier to evaluate your natural hazard risk. There are multiple resources out there that you can use to understand how a hurricane may affect your business:

 

  • FEMA flood maps are still the go-to source of flood hazard information. Plug in the address of your business, home or project site to get a good idea of historic flood risk.

 

 

 

  • On a more local level, there have been a number of efforts to create easy-to-use tools for evaluating flood hazards in the Northeast. There are mapping tools for New Jersey and Maryland that include data on flood, sea level rise and storm surge information as well as data on sea level rise in Delaware.

 

 

 

With so many resources available, the real danger for a causal user is getting overwhelmed and not using any of them. We encourage you to get on one of these easy-to-use websites now and get to know the potential natural hazard risks of your business or other places of interest.

 

 

 

For more on Hurricane Preparedness Week, visit:
http://www.nws.noaa.gov/com/weatherreadynation/news/160404_hurricane_hazards.html

 

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Understanding Differing Impact to Groundwater Standards

Deep Water - Understanding Differing Impact to Groundwater StandardsWorking on environmental projects in four or more states simultaneously can sometimes get a little confusing. One of the more confounding issues is understanding (and remembering) the varying state standards for common constituents of concern. Why is a concentration of benzene in soil greater than 5 parts per billion (ppb) something to worry about in New Jersey but one minute down the road in Pennsylvania concentrations up to 500 ppb are OK?

 

As in most states, the same basic equations describing soil/water partitioning of chemicals are used to derive standards. So why are the end results so different?

 

One reason is the groundwater standard which needs to be maintained. The NJ health-based standard of 0.2 ug/l benzene (not the 1 ug/l practical quantitation limit [PQL] which is used as a benzene standard in practice) is 25 times less than the PA media specific concentration (MSC) of 5 ug/l.

 

The second reason is the assumptions made about how much water infiltrating through the unsaturated zone is diluted in the aquifer. NJ assumes a default value of 20x dilution while PA assumes 100X dilution. But PA MSCs for soil to groundwater can also be set to 100x the groundwater MSC if this value is higher than that indicated by partition equations. This option, also used in some other states, was inserted into the Land Recycling Program regulations for when values based on partitioning seemed too restrictive to implement practically.  For mobile COCs, the 100x MSC will be a higher value while for immobile contaminants the generic (partition equation) value will be higher. Using the 100X MSC rule gives you a 0.5 mg/kg PADEP standard for benzene compared to the NJ standard of 0.005 mg/kg.

 

A slight wrinkle in all this is that in NJ, the standard only applies to unsaturated soils while in PA it applies to both saturated and unsaturated soils. In saturated soils, the PA generic (but not the 100xMSC value) are divided by a factor of 10 and the higher of the two values is chosen.

 

So what does all this mean? Is one set of approaches better than the other?

 

Higher standards help to get past minor environmental issues and focus on the major ones, letting you jump through fewer hoops and at lower cost. But in the end, the realities of fate and transport remain the same. Once you move on to site specific determinations of appropriate standards (e.g. SPLP testing and or unsaturated zone transport models), if the evaluation is done right, standards will converge to about the same place despite a host of state-dependent differences in regulatory paths. Knowing where all those numbers come from helps make that happen.

 

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