Carbon Footprint
Carbon Footprint
The Concept of Carbon Footprint
The concept of “carbon footprint” is described as "the total set of GHG (greenhouse gas) emissions caused directly and indirectly by an individual, organization, event or product" 1. With regard to environmental remediation activities, the vast majority of the associated carbon footprint is directly related to carbon dioxide (CO2) emissions. These emissions result primarily from the use of fossil fuel- derived energy employed throughout the remediation program life cycle and, to a lesser extent, the CO2 emissions resulting from the combustion or biological degradation of organic contaminants.
Carbon Footprint Calculations
Calculating the total carbon footprint of a remediation program at a given site is a demanding and somewhat arbitrary undertaking. Referred to as life-cycle assessment, this process requires that every step in the generation of every product used and every process undertaken in relation to the remediation program be assessed for potential CO2 emissions. The sum of all the emissions calculations is referred to as the total life-cycle carbon footprint.
Total life-cycle assessments, when performed properly, are very detailed. For example, a remediation project employing air sparging would require a life-cycle carbon footprint calculation to be accomplished on the manufacture and use of an air compressor. This calculation alone would include all CO2 emission related to the mining and transportation of various ores, manufacturing of steel, machining of various parts, transportation of parts, assembly, testing, packaging, shipment, warehousing, etc. Often raw materials production and parts manufacturing are accomplished at a variety of locations around the world as producers strive to source low cost goods and labor, thus complicating these calculations further as energy use for transportation varies dramatically with geographic location. Often the assumptions one makes about global supply chain location plays a crucial role in the outcome of the life-cycle carbon foot print calculation for a final finished product.
Currently there is no widely accepted standard dictating the level of detail required in carbon footprint life-cycle assessments nor are there any accepted governing bodies regulating calculation methods or validating claims. Standardization and regulation is certain to come with time as more and more attention is being given to global GHG emissions.
Carbon Footprint of Remediation Projects- Current Practice
Several organizations are now turning attention to encouraging the use of sustainable methods when performing environmental remediation. Several of these organizations are encouraging the practice of calculating the carbon footprint of remediation processes, but at the same time recognize the intense effort and potentially arbitrary outcome of full life-cycle assessments for all products/materials employed in the remediation program (i.e. automobiles, piping, electronics, chemicals, etc.). Thus, the current practice being encouraged is to perform a carbon footprint calculation limited to those activities that occur from the onset or startup of the remediation program itself. This limits the calculation mainly to CO2 emissions related to energy use and to the oxidation of contaminants and chemical substrates employed. Some of the organizations that are encouraging this approach include Network for Industrially Contaminated Land Europe (NICOLE) and the US Air Force Center for Environmental Excellence (AFCEE).
In Situ Remediation –Carbon Footprint of Substrates
When implementing in situ remediation projects, chemical substrates are often utilized. Each of these substrates has a unique carbon footprint associated with its manufacture and use. However, “rules of thumb” widely used in the environmental industry are available that indicate the approximate carbon footprint of various types of substrates when used on in situ remediation projects.
| HRC® or 3D Microemulsion®: Enhanced Bioremediation Electron Donor Substrate | 2.8 lbs CO2 / lb of substrate plus 0.7 CO2 / lb of chlorinated solvents treated2 |
| ORC® or ORC-Advanced®: Enhanced Bioremediation Oxygen Additive | 3.3 lb CO2 / lb of BTEX3 |
| RegenOx™: Chemical Oxidation Substrate | 3.3 lb CO2 / lb of BTEX4 |
If, in the design of a specific remediation project, more detailed carbon footprint calculation data is required on any of Regenesis’ products, please contact Regenesis Technical Services at 949-366-8000 or by e-mail at tech@regenesis.com
References:
1) Carbon Trust UK, 2008, www.carbontrust.co.uk
2) United States Air Force Center For Environmental Excellence, 2009, Sustainable Remediation Tool
3) Unites States Air Force Center For Environmental Excellence, 2009, Sustainable Remediation Tool
4) Regenesis, 2009, assumes complete oxidation without carbonate sink as per AFCEE Sustainable Remediation Tool
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