Enhanced Aerobic Bioremediation

Enhanced aerobic bioremediation is the practice of adding oxygen (an electron acceptor) to groundwater and/or soil to increase the number and vitality of indigenous microorganisms performing biodegradation.

Enhanced aerobic bioremediation technologies such as Oxygen Release Compound (ORC®) and ORC Advaned® are used to accelerate naturally occurring in-situ bioremediation of petroleum hydrocarbons, and certain fuel oxygenates such as methyl tertiary-butyl ether (MTBE), by indigenous microorganisms in the subsurface. The use of these convenient and easy to apply solid oxygen compounds provides a controlled-release, supplemental source of oxygen to the subsurface which Is made available to aerobic, hydrocarbon-degrading bacteria. Oxygen is considered by many to be the primary growth-limiting factor for hydrocarbon degrading bacteria, however it is normally depleted in zones that have been contaminated with hydrocarbons. The stoichiometric ratio of oxygen per hydrocarbon is 3 moles of oxygen per 1 mole of hydrocarbons. By deploying technologies such as ORC and ORC Advanced, remediation practitioners can increase the rates of petroleum hydrocarbon biodegradation at least 10 to 100 times over naturally-occurring, non-enhanced rates.

The use of Regenesis' ORC and ORC Advanced offers the following benefits:

  • Environmentally safe and easy to handle/apply materials
  • Decreased time to site closure - degradation rates accelerated 10 to 100 times faster than intrinsically slow, natural attenuation rates
  • Minimal site disturbance with in-situ treatment - no emplaced aboveground tanks, piping, equipment, etc. and a single product application can last up to 12 months, maintenance free
  • Minimal waste generation - no significant recovered contamination, off-gases or fluid discharges
  • No long-term operations and maintenance - lower costs and greater efficiency/reliability than engineered mechanical systems, oxygen emitters and bubblers
  • Easily combined as a polishing step with in-situ chemical oxidation using RegenOx
  • Experience and a proven track record of success (applied on over 12,000 sites worldwide)

Which Regenesis Oxygen Release Compound is best for my site?

Most remediation practitioners will choose our calcium oxyhydroxide based ORC Advanced material due to its higher active oxygen content and lower cost per unit price. However in some instances our customers prefer to use the original, magnesium based ORC material. Both material are delivered as powder-like material and applied in the same manner, except for the fact that ORC Advanced is a 5.1 oxidizer and is therefore treated differently relative to shipping, handling and storage. The table below shows a side-by-side comparison of the two materials.

ORC:

  • Magnesium based product
  • 10% oxygen by weight
  • Non-oxidizer status for shipping
  • Wide use and regulatory acceptance over 12 year period
  • Higher cost per pound than ORC Advanced

ORC Advanced

  • Calcium Oxy-hydroxide based product
  • 17% oxygen by weight
  • Oxidizer status (increases cost of shipping)
  • Use becoming more widely accepted
  • Lower cost per pound than regular ORC

If you are unsure about which Regenesis material is right for your site, please contact us for a free consultation

Oxygen Release Compound (ORC®)

is the original oxygen releasing product which was formulated and commercialized for groundwater remediation applications in 1994. This product is designed specifically for the in-situ treatment of petroleum-based hydrocarbon contamination or any aerobically degradable substance. ORC is a fine, powdery material that is typically mixed with water and pressure injected into the subsurface. Once hydrated, ORC (a magnesium hydroxide based material) releases up to 10% of its weight as molecular oxygen. This release of oxygen is governed by specialized ORC chemistry which allows for a gradual, controlled release of oxygen over periods of up to 12 months. The available oxygen is then utilized by indigenous microbial populations to naturally degrade contaminants into harmless end products like CO2 and water. ORC was originally manufactured and applied in "filter sock" form. Still popular today, these replaceable 2", 4" and 6" filter socks are designed to be used in wells where they can be installed, removed and replaced upon exhaustion of their oxygen supply.

Oxygen Release Compound Advanced (ORC Advanced™)

is a product designed specifically for the in-situ treatment of petroleum based hydrocarbon contamination or any aerobically degradable substance in the subsurface. Like regular ORC, ORC Advanced is a fine powdery material that is typically mixed with water and pressure injected into the subsurface. Once hydrated, ORC Advanced (a calcium oxy-hydroxide based material) releases up to 17% of its weight as molecular oxygen. Like ORC, this release of oxygen is also governed by specialized ORC chemistry which allows for a gradual, controlled release of oxygen over periods of up to 12 months. The available oxygen is then utilized by indigenous microbial populations to naturally degrade or break down contaminants into harmless end products like CO2 and water.