| Characteristic |
Parameter |
Conditions Indicating Likelihood of NAPL Recovery Is -- |
LOW
NAPL is Unlikely to Be Recovered |
MODERATE
Some NAPL May Be Recovered |
HIGH
All or Most NAPL May Be Recovered |
| Physical Properties of NAPL |
NAPL Viscosity |
High viscosity
(> 2 cpb/) |
Moderate viscosity
(0.9 to 2 cp) |
Low viscosity
(< 0.9 cp) |
| NAPL Volatility |
Low volatility
(vapor pressure < 1mm Hgc/) |
Moderate volatility
(vapor pressure 1 to 10 mm Hg) |
High volatility
(vapor pressure > 10mm Hg)
|
| NAPL Occurrence |
NAPL Location |
Fractures or deep saturated zone |
Capillary zone or shallow saturated zone |
Vadose zone |
| NAPL Distribution |
Residual NAPL |
Potentially mobile NAPL |
Mobile NAPL |
| Geology |
Soil Type |
Clay |
Silt or sand |
Gravel |
| Stratigraphy |
Complex/poorly characterized |
Moderate heterogeneity |
Simple/well characterized |
| Hydrology |
Permeability |
Low
( < 10-4 cm/secd/) |
Moderate
( 10-4 to 10-2 cm/sec) |
High
(> 10-2 cm/sec) |
| Remediation Factors |
Potential for Excavation |
Deep
(NAPL > 15 feet deep) |
Intermediate depth
(NAPL 5 to 15 feet deep) |
Shallow
(NAPL < 5 feet deep) |
| Accessibility |
Poor
(e.g., below building) |
Fair
(some obstructions) |
Good
(no obstructions) |
