scope:

This EM addresses P/C/F systems and includes the following:

• General discussion of theory of precipitation, coagulation and flocculation.

• Precipitation methods.

• Discussion and comparison of coagulants and coagulant aids.

• Pre-design treatability requirements.

• Pre-treatment requirements.

• Operational considerations.

• Equipment requirements.

• Specification preparation.

Purpose. This engineer manual (EM) was written to provide guidance for determining if precipitation, coagulation, flocculation (P/C/F) systems are applicable and guidance on how to properly design, specify, and operate P/C/F systems to remove dissolved heavy metals from aqueous waste streams.

Applicability. This EM applies to HQUSACE/OCE elements and USAGE commands with responsibility for Hazardous, Toxic and Radioactive Waste (HTRW) projects.