The Emerging Use Of ISCO In Environmental Claims

There is an emerging trend that all insurance adjusters and claims managers should be aware of — in situ chemical oxidation (ISCO). This technology is commonly provided by specialized environmental contracting companies in conjunction with a technically competent environmental engineering firm. While in situ environmental clean-ups have been occurring over the past decade, it is classified as an emerging trend because only in the last few years has ISCO entered the mainstream. It is now more widely used by environmental risk management professionals.

What is ISCO?

The phrase in situ is a Latin term that means “in its place.” In situ remediation refers to clean up efforts that take place in the ground, for example, simulating natural processes in the soil or groundwater to remove contamination. Conversely ex situ remediation generally refers to cleanup efforts where contaminated material is excavated and removed to an off-site location. The second part of the term ISCO encompasses the process of chemical oxidation. Simply put, a polluting chemical is transformed from a harmful substance to a safe substance by the placement of a oxidant or treatment chemical into the zone of contamination.

Typically the ISCO process is achieved by injecting a treatment chemical into an area of contaminated soil or groundwater through injection wells. These are drilled into the ground so that contact can be made between the treatment chemical and the polluting chemical. The more contact made between the treatment chemical and the polluting chemical, the higher the likelihood the polluting chemical will be destroyed or transformed into a safe substance.

The treatment chemical could also be placed in the bottom of an excavation where contaminated soil or groundwater are encountered, for example, in the base of an excavation after removal of a gasoline storage tank.

ISCO uses on claims

ISCO is an excellent technology to use for the remediation of properties that are contaminated with chlorinated solvents such as degreasing fluids like trichloroethylene (TCE), dry cleaning fluids like perchloroethylene (PCE), petroleum based contaminants (BTEX, PHC) and products of incomplete combustion (PAHs). There has even been success treating problematic compounds such as PCBs (Polychlorinated biphenyls).

As ISCO has evolved there have been many new products available for the specific destruction of polluting chemicals. For example, potassium permanganate and sodium permanganate are commonly used treatment chemicals that destroy TCE and PCE, with the former being less expensive and the latter remaining longer in the ground creating a more lasting effect.

Treatment chemicals such as base activated persulfate are very effective in the destruction of BTEX and PHC or similar petroleum related polluting chemicals. Proprietary designer chemicals are also available such as RegenOx, which is comprised of an oxidizing chemical with a catalyst to destroy specific polluting chemicals.

Advantages of using ISCO

The advantages of ISCO are as follows:

• the time required to clean-up a contaminated soil or groundwater is greatly reduced when compared to traditional remedial methods (pump and treatment systems, air sparging, etc). Contaminated sites can be cleaned up in months to years compared to decades with traditional methods.

• costs can be greatly reduced for soil remediation when compared to excavation and landfilling of contaminated soil, especially for deeper impacts or impacts located beneath a building.

• costs are greatly reduced for groundwater remediation when compared to traditional methods.

• Contamination can be cleaned up below buildings without demolition. This is an excellent technique for use under historic buildings or monuments.

• remediation can be achieved with minimal disruption to property occupants. Small injection wells/points are used to deliver the treatment chemical to the subsurface versus large excavations for soil removal or the con- struction of buildings to house pumping and treatment systems.

• remediation can be successfully achieved in winter and summer versus biological remediation techniques that only work well in warm temperatures or pumping systems that require heating to avoid freeze up of liquid transfer lines.

• minimal equipment and capital costs are required to get the remedial work started.

• harmful breakdown products such as vinyl chloride, a human carcinogen, are not created during the oxidation process.

• a process that is safe to use in explosive environments versus traditional remedial techniques that use electricity or involve excavation. The photo below shows a site with gasoline contaminated soil that caught fire when an excavator hit a stone and caused a spark during soil removal work.

ISCO selection considerations

The key to a successful ISCO remediation program is to retain an environmental science and engineering firm with a proven track record of designing and overseeing numerous ISCO projects. The firm should be prepared to present client references that can attest to the success of ISCO projects on the contaminants of concern at the subject property upon which the claim has been made. Similarly, the environmental contracting company must have a proven track record of success undertaking ISCO projects in many different situations.

Because ISCO is based on chemical reactions in the subsurface, it is very important the employees fully understand not only the chemistry of the contaminants but also the complexity of the hydrogeology and geology in which the ISCO reactions will take place.

When to use ISCO

Below are examples of recent insurance claims that made use the ISCO technology:

• Hydrocarbon contamination was treated below a five-storey office building in Hamilton, Ont. The contaminants were reduced to well below the MOE standards. The use of ISCO prevented the need to demolish the building, resulting in savings of over $1,000,000.

• Former gas station in Strathmore, Alta. had Benzene, PHC, Napthalene and MTBE contamination in groundwater on the site and below the adjacent roadway. Alberta Tier 1 Standards were achieved in 18 months using a series of percarbonate solution injections at a cost of $750,000. Alternative remedial strategies were estimated to take eight plus years to complete remediation at a costs of well over $2,000,000.

When used properly on environmental insurance claims, ISCO has the ability to eliminate long-tail claims, reduce total claims payout and minimize disruption to the occupants of the contaminated site.

David Wade, P. Geo., CRM, FRM is the president of Canadian operations for Premier Environmental Services Inc. and Premier Risk Management Solutions.