23 Aug Dry Cleaning’s Dirty Little Secret
Reading Time: 5 minutesJerry Seinfeld said, “Did you ever get something on your clothes and brush it off with your hands? That’s dry cleaning.” While Jerry’s dry-cleaning routine is funny, it’s not factually accurate, and those affected by the residual chemicals used in “dry” cleaning tend not to laugh. This article serves as a guide to property owners, developers, and commercial real estate brokers dealing with active or former dry cleaning establishments.
Dry Cleaning Solvents and Why You Should Care If They’re On Your Property
Most of us understand that the “dry” in dry cleaning simply means no water is used. Instead, dry cleaners use a variety of chemical solvents, typically perchloroethene (PCE). PCE is a colorless liquid that is part of a class of liquids known as Halogenated Volatile Organic Compounds (HVOCs). HVOCs are denser than water and, when exposed to air, they readily evaporate into a gaseous state. When HVOCs spills on soil, they infiltrate the soil and percolate downward. Because they are denser than water, when they encounter the water table, they continue to sink. Contrast this with gasoline and heating oil, which are both less dense than water, causing them to float. The tendency of HVOCs to sink below the water table, coupled with the physical stability of such compounds, makes them difficult to remediate. It is for these reasons that HVOC remedial projects, especially when groundwater is impacted, tend to be expensive (more on paying for HVOC remediation at the end of this article).
PCE (and many other HVOCs) can also cause indoor vapor issues. When PCE vapor in soil migrates, it follows the path of least resistance. The coarse backfill that surrounds underground pipes is an ideal conduit for organic vapors, allowing them to gradually infiltrate buildings and create potential indoor air quality concerns.
Recognizing the problem, the dry-cleaning industry has made great strides in mitigating pollution by changing the types of chemicals used and how they’re stored. Notwithstanding these industry changes, the potential for environmental contamination from dry cleaners remains a real threat and concern, and it is estimated that there are more than 30,000 dry cleaning establishments in the United States alone.
Dry Cleaning Due Diligence
There are two common avenues that ESA is asked to explore when investigating potential environmental impacts involving dry cleaners. The first involves active dry cleaners. The second involves buildings or land where a dry cleaner previously operated.
When examining an active dry cleaner, an environmental consultant will determine what kind of cleaning solvent is (and was) used and how and where it is stored. Then, an examination of the actual dry-cleaning equipment and the floor beneath and near the equipment will be conducted to ensure everything is operating properly, there are no leaks, and the floor is intact with no cracks. The consultant will also determine how long the dry cleaner has been in business at the location and how the dry-cleaning operation was run originally. Sometimes, the current operation is determined to be sound, but former practices create cause for concern.
When performing due diligence on a property without an active dry cleaner on the premises, historical records may occasionally reveal that a dry-cleaning facility once operated there in the past. When this happens, a Phase II investigation is needed to determine if the former practice caused any subsurface impacts. Because HVOCs are stable chemicals, even when spills occurred decades prior, their impacts persist and continue to spread in the subsurface. These characteristics make HVOCs particularly pernicious pollutants.
How are HVOCs (especially PCE) Remediated?
Subsurface impacts can be in soil, groundwater, or both. It is always important to eliminate the source material causing the impacts, because un-remediated sources will continue to distribute pollutants into the subsurface.
Sometimes, soil impacts can be relatively easy to remediate. If the impacted soil is readily accessible, it can be excavated and disposed of. This is often the fastest and least expensive way to remediate impacted soil. If the impacted soil lies beneath a building, the soil can be remediated by drawing a vacuum through perforated pipes installed beneath the building in a process called Soil Vapor Extraction (SVE). The extracted vapor is normally then passed through a vapor-phase carbon adsorption unit.
Remediation of HVOCs in groundwater can be difficult, complex, and expensive. There are a variety of treatment methods available, none of which is “the best.” So, how does one decide which treatment methodology to use? The answer, like many of the things that environmental consultants do, is a combination of both art and science. Following are some of the more common groundwater treatment technologies available:
Chemical Oxidation – This method requires the use of a chemical oxidizer (normally some form of concentrated peroxide). If there is a large pool of contaminants in the groundwater and its extent is well defined, this can be an effective method. Oxidizers are exothermic and, if not used carefully, can effervesce to the ground’s surface, exacerbating the problem and causing harm to people, equipment, and buildings.
Bacteria – Chlorinated solvents must be bioremediated anaerobically. When oxygen is present, the compounds will biodegrade into a toxic byproduct called vinyl chloride. Anaerobic bioremediation works well, but the bacterially treated groundwater must make physical contact with 100 percent of the mass of contaminants for it to work.
Groundwater Pump and Treat – This is the “old fashioned” treatment method where groundwater is pumped to the surface and passed through an air stripping tower and, possibly, through activated carbon. The treated water is then discharged. This method usually requires an air permit for the stripping tower and water discharge permit for the effluent.
Sparging in Conjunction with Soil Vapor Extraction (SVE) – This is an interesting technique where air is bubbled through the impacted groundwater. This physical action (called sparging) tends to promote the volatilization of the HVOCs. The released vapors are then run through an SVE system.
Dechlorination – This remedial method relies on proprietary chemical compounds that enhance anaerobic bioremediation.
So, again, to determine the most appropriate remedial technology for a given site requires a combination of both art and science. The environmental consultant must gain a clear understanding of the horizontal and vertical extent of the impacts, the depth of the groundwater impacts, the nature of the impacted property (is there ample space to work or is the business part of an active strip mall) and whether the contamination is limited to just the soil, or if it has impacted both the soil and the groundwater. This information should then be analyzed by experienced environmental remediation professionals to identify a remedial solution that makes sense.
Paying the Cost for Dry Cleaning Remediation
Throughout the 32-year history of ESA Environmental Consultants, we have always sought to identify “other people’s money” to pay for our clients’ environmental services. Because HVOC remediation problems are among the more expensive projects encountered, ESA always advises our clients to look for old insurance policies that may pay some or all of the costs.
In conclusion, if you have a potential or known HVOC contamination problem, seek assistance immediately from an environmental consultant that has the expertise, experience, and integrity to help you navigate this challenging issue. The sooner you have a clear picture of the situation and know what needs to be done, the better your position when dealing with regulatory authorities and, if considering a sale, with real estate brokers and buyers as well. It also helps to get advice from a trusted environmental attorney who, in concert with your environmental consultant, will create a solid team that can confidently manage your remediation project.