Henry's Law

Dissolved Oxygen

Bio-enhancing contaminated groundwater with oxygen to raise DO levels is commonly performed to create or enhance a natural aerobic biodegradation of contaminants. At standard temperature and pressure (25C, 14.7 psi), the solubility of dissolved oxygen in fresh water is approximately 39 mg/L.

The solubility of oxygen in water is dependent on temperature and pressure:

  • Temperature: solubility increases with decreasing temperature
  • Pressure: solubility increases with increasing partial pressure of oxygen in accordance with Henry's law

Henry's Law:

H = C / P

H = Henry's constant for O2 in water at a given temperature and pressure ( H is different for every gas, temperature, and solvent)
C = concentration of O2 in water
P = Partial pressure of O2

Practical Implications for O2 bio-enhancement remediation techniques:

The solubility of DO in water will increase with depth to contaminated groundwater plume (i.e. depth is proportional to increased pressure and decreased temperature)