Month: September 2016

Minimizing The Impact of a Cleanup

Posted on by EnviroForensics Staff

It can feel like their whole world has been turned upside down when our clients receive the news that they have an environmental contamination issue on their property that could take hundreds of thousands, or millions, of dollars to clean up. Adding to this sense of panic is the knowledge that active remediation activities can be intrusive, time-consuming, and potentially disrupt business operations.  The risk of losing loyal customers during forced down-time can keep anyone up at night. That’s why EnviroForensics goes to great lengths to work with drycleaner owners to make sure we’re doing our job while also allowing them to do theirs.

Recently, we began the process of remediating a Site in Indiana where the best remedial technology necessitated work inside the drycleaner building.  The owners needed to keep the business running uninterrupted, and we needed to work with them to make that happen. We put our heads together and came up with a schedule and approach to install our remedial components while minimizing the impact on the drycleaner’s ability to conduct normal business.

We moved most of the drilling outside to minimize impact to the business.
We moved most of the drilling for our ozone sparge points outside to minimize impact to the business.

The first task was the installation process involved installing ozone sparge points into the groundwater beneath the Site building. Ozone sparge technology is able to oxidize contaminants in groundwater through the injection of ozone through subsurface injection points. For this phase, we devised a way to stay out of our clients way altogether by drilling angled sparge points from outside of the building to reach the contaminants beneath the building.  This innovative approach allowed for normal cleaning operations to continue inside the building during the drilling activities.

The second step of the installation process was a little bit trickier since it necessitated the installation of soil vapor extraction (SVE) wells and above ground piping inside the building.  We were able to schedule this portion of the work during February, which has historically been one of the slower times of year for our clients. For two weeks, dry cleaning and laundry operations were conducted as normal from 8am to 2pm before the building shifted into remediation mode.  The front desk and pick-up/drop-off operations continued as usual while our experienced install team went to work installing the SVE system from 2pm until 10pm each night.  Pulling those second shift hours paid dividends for our dry cleaning partner by allowing them to keep the doors open and meet the cleaning needs of their customers.  Now, while the public gets their dry cleaning finished on time, our remediation system is keeping a low profile, cleaning up soil and groundwater impacts.

Staying open is a big deal. For some business owners, it’s absolutely necessary to keep their heads above water. For others, it’s just a powerful statement to their loyal customers that they can continue to serve them in spite of their commitment to improving environmental conditions at their site. Keeping our client’s best interests in mind is a vital part of our job, and we demonstrate this on each and every project through team work and innovation to develop new solutions to old problems.  We work hard behind closed doors so yours can stay open.

This poster is prominently displayed outside the actual drycleaner. It was put up to help maintain transparency between the business and its loyal customers as well as establish the drycleaner owners as stewards for the environment.

ERD Delivering Effective Remediation to Indiana Drycleaner Site

Posted on by Alex Miller

ERD injectionsEnviroForensics is excited to report yet another Enhanced Reductive Dechlorination (ERD) success story. Our staff has been employing this technique for more than a decade at sites across the state and the Midwest, and it has, once again, delivered the desired effect to an impacted drycleaning property in Lafayette, Indiana.

Contamination consisting of the chlorinated solvent, PCE, was discovered in the subsurface at the Vogue Cleaners property, in an interbedded sand and clay formation. Per the Remedial Work Plan approved by the Indiana Department of Environmental Management (IDEM), we conducted an excavation on the side of the building, digging as deep as 21-feet below ground level to remove impacted soil.

In order to address groundwater impacts, we used an ERD application augmented with zero-valent iron (ZVI – an in-situ chemical reduction [ISCR] agent) to address those problem areas.  Naturally occurring bacteria called dehalococcoides (DHC) were present in the groundwater onsite and in the area of the property. As we’ve explained in past blogs, these microorganisms naturally break down chlorinated solvents by cleaving off chlorine molecules and replacing them with hydrogen particles. In order to maximize the use of these microorganisms, we injected a substrate called Lecithin mixed with ZVI ®, developed by Peroxychem, as the carbon source. Additionally, a substrate called Provect IR (produced by Provectus), which also had ZVI as an ISCR agent, was used in a different part of the site because it was determined to be more effective for the subsurface conditions found in that area.

The addition of the substrates immediately began the reduction of the PCE concentrations followed by sustained contaminant destruction over time.  The first round of ERD injections proved to be very successful. PCE concentrations, which in some spots were as high as 4,000 micrograms per liter, were knocked down to less than laboratory detection limits. These results show the typical success of ERD technologies when implemented by experienced professionals.  The remediation at the site has progressed quickly and effectively, and closure procedures are now being discussed with IDEM.  With this effective and efficient remediation we anticipate our client will receive a “covenant not to sue” from the State of Indiana shortly after site closure.

EPA Adds West Vermont Street Site to Superfund List

Posted on by Alex Miller

Following nearly a year of speculation, an 18-acre groundwater contaminant plume on Indianapolis’ West Side, has landed the area on the U.S. Environmental Protection Agency’s new Superfund list.  Superfund is a federal program that aims to address some of the most contaminated land and waterways in the country.

In September 2015, the EPA made the proposal to put the West Vermont Street groundwater site on the National Priority List. In 2009, Marion County Health Officials had discovered high concentrations of vinyl chloride (a breakdown product of drycleaning solvents) in the drinking water of three homes near the Allison Transmissions plant, just south of the Indianapolis Motor Speedway.

Proposal Map for West Vermont Street Superfund Site. Courtesy: United States Environmental Protection Agency
Proposal Map for West Vermont Street Superfund Site. Courtesy: United States Environmental Protection Agency

 

According to EPA officials, there were at least 20 other potentially affected homes in the area, and immediate action was taken to ensure the health and safety of these homeowners. Utility workers diverted the water service from the underground water wells in the area to municipal water.

Even with this measure in place, EPA officials determined the potential danger of the groundwater plume was too much to ignore. Investigations confirmed the migration of the plume could put as many as 18 thousand people at risk of becoming exposed to the contaminant.

EPA officials are now conducting further investigations to delineate the horizontal and vertical nature of the plume, filling in data gaps, and identifying all potential exposure pathways including vapor intrusions. A few potential responsible parties have been identified as a result of their historic operation and known individual contaminant releases on their properties.

EnviroForensics has been involved in SuperFund sites like this one around the Indianapolis area, including the Keystone Corridor Project, and we know how important this work is. We look forward to providing additional information as new developments arise regarding this project.

A Vapor Intrusion Success Story

Posted on by EnviroForensics Staff

Sometimes detecting and addressing a vapor intrusion pathway is like a giant game of whack-a-mole. As soon you knock one down, another one pops up, and so on and so forth. One of our teams recently encountered this issue, having discovered that their initial mitigation efforts had not decreased the concentration of tetrachlorethene (PCE) inside an apartment located above a dry cleaner.  Despite this setback, our team dusted themselves off, and went back to work, going by the old addage; if at first you don’t succeed, you try again.

To give you an idea of what we were working with, our site building is a 2-story structure with a dry cleaner on the first floor, and an apartment on the second. The dry cleaner is now a drop-off only location, but had conducted on-site cleaning in the past. We discovered PCE in the sub-slab vapor underneath the structure, which helped us determine there were vapor intrusion risks to both the dry cleaner building and, perhaps more importantly, the apartment above it. We installed a sub-slab depressurization system (SSDS) to address this issue.

Unfortunately, that did not solve the problem. Indoor air PCE concentrations in both the first floor dry cleaner and second floor apartment remained above the residential vapor action level despite the operation of the SSDS. The concentrations were similar on both floors, which suggested direct physical pathways for indoor air movement. The HVAC systems that services these spaces were the most likely culprit.

Armed with this new knowledge, we focused our efforts on the first floor room that houses both of the HVAC systems. We first sealed up the mechanical room, using an air-tight door gasket and sweep. Duct work and piping penetrations in and out of the mechanical room were also sealed and a furnace filter cover was added to prevent the apartment furnace system from potentially capturing vapors from the first floor. We then installed door gaskets between the first floor store and the second floor apartment stairway. The final touch was an energy recovery ventilator (ERV) installed on the apartment’s furnace to increase fresh air exchange.

Early returns suggest this latest attempt to address the problem was successful. The first post-mitigation indoor air sample collected from the apartment did not contain PCE above laboratory detection limits. Our team will conduct a confirmation air sampling event during the upcoming winter months, when conditions will be ideal for a “worst case” air assessment.

In the Environmental Cleanup business, there really isn’t any room for failure. The preceding is a good example of the trial and error we go through when looking for all potential vapor intrusion pathways. Using the experience and ingenuity we have managing contaminations like this, we were able to come up with another solution. And, at least in the short run, it appears the residents of that 2nd floor apartment can breathe easy without having to worry about the potential health risks of exposure to PCE.

image was a courtesy of Washington State, Department of Ecology
image was a courtesy of Washington State, Department of Ecology

Putting the Forensics in EnviroForensics

Posted on by EnviroForensics Staff

When you hear the word “Forensics”, often times it conjures up images of television detectives. You imagine a hard-boiled cop working on his second cup of coffee, lifting up the caution tape on the police perimeter, so he can walk onto the crime scene and begin to reconstruct what happened. He collects clues like patches of fabric, hair and blood samples. Talks with witnesses and potential suspects; interrogating the shifty ex-con whose fingerprints are all over the crime and whose past won’t afford him the benefit of the doubt. It all invariably leads to the climactic finish with the unlikely perpetrator being caught in the final ten minutes of a neatly wrapped 60-minute serial. Environmental Forensics is kind of like Hollywood forensics – we reconstruct the past to answer questions like “who done it?”, and its application can assist in a multitude of ways when dealing with an environmental liability.

Environmental forensic investigations differ from traditional environmental investigations in that the objective is not to identify human health exposure pathways or answer remedial feasibility and design questions, but rather to answer specific questions about historical contaminant release scenarios.  The leading question is typically, “who is responsible?”  To answer this question, it is often instructive to determine where and/or when the release occurred.  Other potentially useful information may include contaminant type and indicator parameters detected with the contamination.  The need for a forensic investigation often comes about through environmental litigation proceedings, but forensic evidence can also be used to support insurance claims, out-of-court settlement proceedings, or other questions that may be aided by understanding the contaminant release and migration history at a site.  We have many tools to use for this purpose, including Fate and Transport Modeling (most common), Compound Specific Isotope Analysis, Principal Components Analysis, and Chemical Ratio Analysis, to name a few.

Just like our Hollywood example, forensic evidence in an environmental case also plays a huge role in the legal side of things.  We deal with the question of “who-done-it” a lot.  After all, figuring out who’s responsible/liable is what sets this whole thing into motion in the first place.  Often times, there are multiple, overlapping plumes with more than one potentially responsible party.  Forensic evidence can help us determine who is at fault, if there are any other responsible parties, and if a suit or claim is defensible.

It may not be as dramatic or as glamorous as the criminal forensics you see on TV, but environmental forensics is still a very important and useful practice.  The tools involved allow us to determine the nature of a release of a chemical contaminant, the timing of release, and perhaps most importantly, the source of release.  These facts not only help us better understand the site and recommended courses of action, but also aid in cost allocation, identify responsible parties, and support litigation proceedings.