Santa Susana

Operable Units and Groups

Surficial Media Operable Unit (SMOU)

The Surficial Media Operable Unit (SMOU) is comprised of saturated and unsaturated soil, sediment, surface water, near-surface groundwater, air, biota, and weathered bedrock. Near-surface groundwater is found at shallow depths and is present within the alluvium or weathered bedrock (see illustration). Near-surface groundwater is also sometimes referred to as shallow groundwater because of its close proximity to the ground surface.

Chatsworth formation Operable Unit (CFOU)

The Chatsworth formation Operable Unit (CFOU) is comprised of the Chatsworth formation aquifer and includes both saturated and unsaturated unweathered (competent) bedrock (see illustration). Groundwater present in alluvium, weathered bedrock and unweathered bedrock and throughout forms an active hydrologic continuum in which the water in the alluvium and weathered bedrock predominantly flows into the unweathered bedrock (i.e., the Chatsworth formation).