35 Ill. Adm. Code 604.800
Lime or Lime-soda Process
Section 604.800 Lime or Lime-soda Process
a) Design
standards for rapid mix, flocculation and sedimentation are in Subpart E.
b) When
split treatment is used, an accurate means of measuring and splitting the flow
must be provided.
c) Before
installation of lime or lime-soda processes, the community water supply must
determine the carbon dioxide content of the raw water to evaluate the efficacy
of installing aeration treatment.
d) Lime
must be fed directly into the rapid mix basin or mixing chamber.
e) Rapid
mix detention time must be no longer than 30 seconds, with adequate velocity
gradients to keep the lime particles dispersed.
f) The
softening process must include equipment for stabilization of water softened by
the lime or lime-soda.
g) The
use of excess lime is not an acceptable substitute for disinfection.
h) The plant processes must
be manually started following shut down.