FAQs

Questions about the Matrix Enhanced Treatment System™ (METS) for remediation of contaminated soils:

1. What is the Matrix Enhanced Treatment System™?

The Matrix Enhanced Treatment System (METS) is a major breakthrough in the practical science of remediating contaminated soils. METS was designed and developed after extensive research into other advanced and alternative remediation technologies. Most of these predecessor technologies have significant limitations, making them too costly to operate and often unreliable when confronted with extensive contamination and/or diverse soil conditions.

METS overcomes these drawbacks to a degree no other commercially available remediation system can match. Moreover, METS is simple in design and application. It is based entirely on proven contamination treatment products and soil processing designs. METS is capable of treating virtually any type of contaminant -- and combination of contaminants -- in virtually any post excavation soil matrix.

2. What makes METS different from other soil remediation methods?

Treatment cost, the designers of the METS process knew from years of experience with other remediation technologies that degrading or neutralizing contamination should be simple and cost effective if you are able to attack the contaminant at the molecular level. However, given the wide variation in soil conditions and composition that occurs in nature, pockets of contamination can easily hide from other remediation technologies. The METS designers realized that, for a remediation method to be reliable, we required a more efficient and thorough means of processing the soil and blending the decontamination reagents or microorganisms into the soil. After years of research and testing, we proved and patented the right combination of elements to accomplish that goal. The result is METS.

3. How does METS work?

The METS remediation process equipment is about the size of a large 4x4. It is fully mobile and self-propelled. Previously excavated soil is deposited in the hopper at the top of the apparatus by a conventional front-end loader. Very large debris, such as rock, concrete or asphalt, is usually screened off during project development. From the hopper, the soil is transferred in a regulated flow to a custom designed processing mill. The mill impacts and shreds the soil, while blending a treatment solution (chemical, biological, or both), along with air and moisture, into the soil using a method that is proprietary to MB Environmental. The contaminant molecules in the soil are already being degraded or neutralized by the time the soil emerges from the processing mill. The treated soil may be deposited directly to the ground from the mill or a conveyor system for higher stacking/windrowing depending on site space constraints.

4. Why does METS Work?

There is, in nature, a wide variability in soil conditions and soil content, even within small distances. This is the principal barrier to effective and efficient remediation of contaminated soil. The METS process is designed to eliminate this variability in the soil while introducing one or more chemical or biological reagent(s) known to degrade and/or neutralize the specific contaminants in that soil. In other words, METS is able to tailor the choice of chemical and/or biological reagent to the specific type and severity of contamination, and to the specific soil conditions at a site. Second, the METS process reduces the soil to a fine particle state in order to maximize access to the contaminant molecules. Third, the METS process ensures the even distribution of the reagent(s) throughout this soil matrix, and the degradation/neutralization is completed before the soil loses its homogeneous and fine particulate composition. Finally, to improve speed and efficiency, the METS process creates a relatively high level of air entrainment in the soil, along with a carefully calibrated level of moisture content.

5. Is METS an ex-situ or in-situ process?

METS is an ex-situ process -- meaning that it works only with soil that has been excavated. This makes it possible for the soil to be deposited by a front-end loader into the METS processing equipment. Usually all of the contaminated soil is excavated and stockpiled on the site prior to beginning the treatment process. However, depending on time and site constraints, soil may be taken directly from excavation to the METS processing equipment. Also, on very large projects, it may be more efficient to excavate, stockpile and treat portions of the soil in phases.

6. Does METS work with soil that has not been excavated?

METS only works with previously excavated soil. The fact is, finding pockets of contamination that are hidden throughout unexcavated soil is, at best, a hit-or-miss proposition. That is not good enough to meet our goals of clean and safe soils. Excavating the soil is an essential step for any remediation technology that attempts to reduce contamination to a safe level.

7. What happens to the contamination during the METS process?

The METS remediation process is based on thoroughly blending safe, decontaminating reagents and/or biological cultures into a suitably prepared soil matrix that includes proper moisture and aeration in a single operation. As a result, the contaminants are either destroyed or rendered environmentally inert as soon as the reagents or microorganisms come into contact with the contaminant molecules. This treatment process, which is proprietary to METS, ensures that the contaminated soil can be remediated to an environmentally safe level in the shortest possible time. Our biological treatment can produce desired results in days instead of the months often required by other bioremediation techniques and methods.

8. Is METS a bioremediation process?

Depending upon the type and concentration of contaminant, and other site conditions, the best and cheapest choice for treatment using METS may be with a biological agent. In every case, the cultured microorganisms are drawn from nature, typically from locations where the microorganisms evolved to live off substances that we consider to be contamination. Even better, the METS process stimulates microorganisms that are already present in the soil being treated. It is not unusual for these preexisting biological cultures to be a big factor in degrading the surrounding contamination, once they have been stimulated.

9. Is METS environmentally safe?

In no case does METS create or produce environmentally unsafe byproducts, sludge or waste. The contaminants are destroyed or neutralized during the process -- no contaminants are hauled away for treatment or disposal somewhere else. At no time is there a threat to surrounding land, groundwater or air. In fact, many of the chemical reagents and biological cultures we use are also commonly used in the cleaning of sewers, storm drains, water supply systems and other facilities that are involved in the circulation of water.

Questions about using METS to solve your specific soil contamination problems:

1. How does METS treat different contaminant types and concentrations

METS is designed to work with any chemical reagent or biological treatment product that is or can be delivered in an aqueous solution or solid powder/pellets. The choice of what to use in a given project is determined from analysis of the contaminant or combination of contaminants in the soil, and from analysis of the soil composition, moisture content, pH, etc. For example, commercially available products that are commonly used to degrade hydrocarbons as part of various cleaning and degreasing applications, can be adapted successfully by METS. Other products that can be adapted for METS are based on an exothermic reaction as well as oxygen release. This reaction, depending upon the catalyst involved, degrades a hydrocarbon molecule to its carbon and hydrogen elements.

Metals (ie; soluble lead) can be detoxified/desolublized by chemical bonding at the molecular level, resulting in compounds that are stable and benign. METS is also able to apply a variety of products that release cultured microbes proven to degrade and/or neutralise various types of contaminants. In all known cases, these are naturally occurring biological organisms that have been found to thrive in environments where these contaminants have been introduced by man made events or by natural causes.

2. Is METS suitable for a very large project?

The METS process is suitable for a project of any size. Depending on the size of equipment being use, our largest processors can treat in excess of 300 tons of contaminated soil per hour. By using more than one processor at a project site, each of which is served by a separate loader or team of loaders, a huge project can be completed in a surprisingly short time.

If site constraints preclude using multiple processors, a large project can be tackled in a phased approach. That is, a section of contaminated soil can be excavated, treated, tested and returned to the ground, making room for treatment of the next section.

3. Is METS suitable for a very small project?

METS is designed to be practical and cost effective for very small projects. The only condition is that the site has room for the METS processing equipment (about the size of a large 4x4) and a small loader.

4. Is METS suitable for treating very high concentrations of contaminant?

METS is capable of treating any level of contaminant in the soil. In extreme situations where the concentration is very high (for example, soil that has become saturated with hydrocarbon based sludge), it may be necessary to add soil to the mixture simply to ensure than the METS processing is efficient. It is additionally possible that at very high concentrations METS can actually assist in a higher recovery rate of products such as tar/oil sands.

5. Can METS treat more than one contaminant at a time?

The standard METS processing equipment is designed to treat more than one contaminant during a single pass through the system. It is also possible to treat a stock of contaminated soil with both a chemical reagent and biological culture in a single pass through the system.

6. What if the soil cannot be excavated for one reason or another?

In a project where the soil cannot be excavated (for example, because it is beneath a building), METS alone will not solve the problem. However, in a situation where only a portion of the soil cannot be excavated, METS is the most cost-effective way to remediate the soil that can be excavated. That way, conventional techniques for in situ remediation, which are generally slow and costly, should be employed only where the option for excavation is completely foreclosed.

7. Are there any environmental or safety considerations involved with using METS?

There are no special environmental or safety hazards or risks associated with METS. Specifically, with respect to:

• Chemical hazard. The chemical and biological treatment products used in the METS process are biodegradable and environmentally benign. In most cases EPA/UL approved.

• Noise. The METS processing equipment, when operating, produces a noise level comparable to a medium sized residential gasoline generator. The noise level is typically less than that produced by the loader equipment being used to dump contaminated soil into the machinery.

• Air pollution. The METS processing equipment meets relevant emission control requirements for such equipment and our current units meet or exceed Tier III specifications.

• Water pollution. There is no contact with groundwater during the process since the contaminated soil is already excavated and stockpiled. Nor is there any release of chemicals or biological products, diluted or undiluted, into public waterways, public sewers or storm drains. In fact, some of these products are in fact prescribed for use in cleaning sewers and storm drains. All METS Licensees are trained to assure that reagents are stored safely on site to avoid spillage and provide containment.