GMS:SEAM3D Biodegradation Package

The Biodegradation Package is used with the SEAM3D model to set estimated parameters for the disintegration of materials by bacteria, fungi, or other biological means. Estimation of model parameters for biodegradation may be based on laboratory measurements, published values, and theoretical estimates. To produce maximum flexibility, SEAM3D allows parameters to vary across the aquifer layers and among the various substrates and electron acceptors for biodegradation.

The dialog is reached through the SEAM3D | Biodegradation Package command.

Minimum Concentration

SEEM3D Biodegradation Package dialog showing the Minimum Concentration tab

The Minimum Concentration tab has the following options:

• Number of bio steps per transport step
• Screen output cell
• Microcolony minimum concentration
• Minimum concentration – This table allows setting a minimum concentration for a defined species. If the concentration of defined species falls below a minimum value, then utilization of that species ceases.

Starting Concentration

The Start. Conc. tab allows setting an initial concentration for defined species. Clicking the Edit button will open an array editor called the Starting Concentration Array.

SEEM3D Biodegradation Package dialog showing the Starting Concentration tab

Electron Acceptor

This tab allows setting the inhibition coefficient and the Yeild coefficient for defined species.

SEEM3D Biodegradation Package dialog showing the Electron Acceptor tab

General Coefficient

This tab allows setting the Product coefficient, Methane coefficient, and Daughter coefficient for certain species.

SEEM3D Biodegradation Package dialog showing the General Coefficient tab

Use Coefficient

There are two use coefficients that can be defined: the Electron acceptor use coefficient and the Nutrient use coefficient.

SEEM3D Biodegradation Package dialog showing the Use Coefficient tab

Saturation Constant

SEEM3D Biodegradation Package dialog showing the Saturation Constant tab

• Hydrocarbon half saturation constants
• Electron acceptor half saturation constants
• Nutrient half saturation constant
  • Use all nutrients to limit growth
  • Use minimum nutrient to limit growth

Rate

• Death Rate
  • Calculated by model
  • No death
  • Constant
• Maximum specific rate of substrate utilization
  • Vary spatially – When turned on, allows spatial variability for the maximum specific rate of substrate utilization. Clicking the Edit button will open an array editor called the Maximum Rate of Substrate Utilization Array.

SEEM3D Biodegradation Package dialog showing the Rate tab