Choose a Destination Construction Evironmental Division Forestry About Cam-Mac Group Inc. Safety Products Press Contact Us and Enquire Home

Bioremediation

   The controlled destruction of hazardous materials by natural methods of bioremediation offers unique and extremely diverse opportunities for the clean up of contaminated environments. Biological treatment is important because the end results are simply biological cell mass, carbon dioxide and water, effectively eliminating liabilities associated with other methods of treatment.

   Bioremediation is not a novel technology, and relies either on the indigenous bacteria of the site or inoculation with other naturally occurring, contaminant specific microbes. The concepts of bioremediation are well founded, and are implemented through enrichment with appropriate nutrients and by increasing oxygen transfer within the contaminated environment.

   All living organisms require sources of energy to develop and sustain their populations. In biological treatment, the contaminant is one of the sources of food and energy for the microbes. Their activity is dependent on the availability of water and oxygen, nutrients, temperature and pH.

   During the microbial growth process, organisms incorporate certain amounts of nutrients. Nitrogen and phosphorous must be available and maintained at sufficient concentrations with respect to the available organic carbon in the limiting nutrient. To ensure control of the physical environment during the remediation process, variables which must be considered to achieve success are: - proper moisture content (varies with soil type),

-pH in the range of 6-9,

-temperature as near optimum for the degrading organisms as can be reasonably achieved (to a certain limit, the higher the temperature, the faster the degradation process),

- and the dissolved oxygen content in aerobic systems at optimum saturation with air.

   Cam-Mac can supply all nutrient, pH adjustment material and our unique mixing head allows for maximum air exchange to take place. In situations where mixing is not possible, Cam-Mac can supply a chemical oxygen supply for the microorganisms.

   Bioremediation is defined as a process by which oxygen, nutrients and cultured microbes are applied to a contaminated site in an effort to promote the degradation of contaminants. Bioremediation is best accomplished with bioaugmentation, the addition of large numbers of selected microorganisms grown in the laboratory. In comparing bioaugmentation with natural degradation, the former greatly increases the rate of degradation. The microorganisms naturally present that can degrade petroleum products are usually present only in the upper few inches of soil and in lower concentrations. These organisms are greatly diluted when mixed with a large amount of excavated soil from deeper levels. The dilution factor can be so large that it takes an excessively long time, if ever, to establish a working population of suitable organisms.
More on Bioremediation and Alternatives to BioremediationClick Here

  With bioaugmentation, microorganisms are applied to the soil to give an initial population of over three million organisms per ounce of soil. Studies have shown that this concentration ensures that a sufficient population will be maintained at this level. As the project progresses the population of petrophilic organisms will show up to a one-thousand-percent increase as they digest the contaminants.

H-Bac 1, Cam-Mac Construction’s blend of microorganisms and stabilized enzymes, is a synergistic group of microorganisms that digest short and long chain hydrocarbons. These organisms are non-pathogenic and use petroleum products in the soil as a source for both carbon and energy. These microbes convert the contaminants to cell mass, carbon dioxide, and water. The stabilized enzymes allow the immediate start of the breakdown of the hydrocarbons so that they are available for the microorganisms to consume. While the microorganisms are developing sufficient amounts of enzymes to do the job.

Sur-Fact consists of an entirely biodegradable blend of surfactants and penetrants that break the hydrocarbons loose from the soil and breaks most chains. In the emulsification process, Sur-Fact separates the long-chain molecules exposing a multitude of end-chain carbons. It is to these end-chain molecules that the microorganisms attach to start the degradation process. Sur-Fact helps to stimulate biological activity by increasing food chain availability, thus allowing a rapid degradation of the contaminate. Sur-Fact is effective in hard, soft, salt, fresh, and brackish water environments, and is equally effective in a soil matrix. This even emulsion allows maximum exposure of the contaminate to the microorganisms, thus speeding up the degradation process.

  Nitrogen is needed for biosyntheseis and can be obtained by microorganisms from either inorganic or organic sources. Nitrogen, along with other nutrients, are added to attain the correct carbon/nitrogen ratio.

  The oxygen level is quite often the rate limiting factor in the biodegradation of petroleum based products. Microbial activity is most frequently limited by insufficient oxygen due to slow rates of diffusion in the interior of the soil layers or piles and into the center of soil aggregates. Generally, the greater the mass of oxygen that can be distributed, the more rapid and complete the cleanup. With Cam-Mac Construction's unique soil mixing head approximately 4 air exchanges occur during a mixing as opposed to less than 1 when a bucket is used. When air is forced through perforated pipes that are contained in a bio-pile, it takes the path of the least resistance and consequently some of the contaminated soils do not get the required oxygen exchanges. Please refer to attached "Innoculants: Microorganisms and Surfactants, Soil Conditioner / Mixer".