|
State, city
work to solve
waste treatment problem
Northern Indiana Times-Union -
8/12
The Indiana
Department of Environmental Management is working with the Warsaw
wastewater treatment plant to identify and correct problems at the
facility in Boggs Industrial Park.
While the cause
is not yet known, it appears the plant has been unable to
sufficiently treat its waste before discharging it into Walnut
Creek, according to an IDEM news release.
Last weekend a
fish kill claimed a number of shad in Walnut Creek prompting IDEM
to examine the treatment plant’s effluent stream. IDEM personnel
noted discolored discharge from the plant that included solids. In
a plant that is functioning properly, solids should settle out of
the waste steam instead of remaining suspended.
Friday, public
works superintendent Lacy Francis said the “fines” – tiny
particles of sediment that remain after wastewater is heated and
filtered – overflowed the sludge tanks into Walnut Creek.
IDEM inspectors
suspect the presence of surfactants (a soap material) as a
possible contributor to the suspension of solids. Surfactants,
which may have come from industrial discharge, can prevent solids
from settling during the treatment process.
Low dissolved
oxygen levels were observed downstream from the plant and in the
Tippecanoe River, to which Walnut Creek is a tributary.
No environmental
warnings have been issued for either waterway.
According to
wastewater treatment plant supervisor Dick Van Dyne, the spill
into Walnut Creek ended this morning.
The facility
faced several problems at once leading to last week’s troubles,
he said.
The sludge tanks
were at capacity pending permits for land application. Those
permits were approved last week.
Before the land
application took place, an unknown soap material (surfactants)
entered the tanks, breaking the sludge into bits too small to
capture the “fines.”
“The soap
material is either different from or at levels we haven’t had
before,” Van Dyne said. “IDEM is conducting a CTAS test to
determine the surfactant and its quantity. It’s something other
than what we’re used to.”
Local industries
have their own pretreatment plants that ordinarily remove possible
contaminants.
IDEM will track
down the source of the suspected surfactants. Samples are on their
way to a laboratory in Louisville, Ky., for testing.
Van Dyne is sure
the problem is organic, however, and not stemming from an
introduction of metal.
“We had to
remove the bulk of the sludge from the system in a very short
time,” he said. “When the sludge is in a young stage, solids
don’t settle as easily. The bacteria has to grow and
accumulate.”
It doesn’t take
a whole lot to mess up the delicate environment of a sludge tank.
Over the weekend,
polymers were added to the tanks to attract solid particles, a
process known as deflokulation. Currently the sludge is “too
young” to attract solids on its own.
It will have to
regenerate its own population of bacteria, and that will take
several days, the superintendent said.
IDEM is taking
the following steps to help stabilize the plant and the creek:
• Using
aerators to raise the level of dissolved oxygen in the creek;
• Assisting the
treatment plant in removing solids;
• Talking with
local industries to determine the composition of the waste stream
received by the treatment plant;
• Urging the
city to work with industrial discharge to minimize discharges; and
• Monitoring
plant activity and efforts to correct the problem and assisting as
needed.
NOTICE: In accordance with Title
17 U.S.C., section 107, some material is provided without
permission from the copyright owner, only for purposes of
criticism, comment, scholarship and research under the "fair
use" provisions of federal copyright laws. These materials
may not be distributed further, except for "fair use,"
without permission of the copyright owner.
|