"Metal Hits at WWTP

1
"Metal Hits at WWTPs

• Class A EQ Biosolids
• To Class F
• And Back Again

2
Cadillac WWTP

• Class B tertiary treatment plant
• Grit removal
• Primaries
• Aeration tanks
• Secondary's
• RBC
• Sand filters
• Anaerobic digesters
• Discharge into trout stream

3
The Story

• Microscopic Evaluation
• Hauling Biosolids
• Point Source Study
• Wet Test
• We Have a problem

• Confirm Tests
• Investigation
• Incoming Trunk lines
• Factories
• On the trail of the Guilty
• Sampling Trailer

4
Story (continued)

• Guilty Party
• The Meeting
• Results
• Toxic Sludge
• Bidding
• Geotubes

• Geotubes II
• Disposal
• Outcome

5
Microscopic Evaluation

• Evaluate three Activated sludge slides a day
• Noticed decrease in life on Mondays
• Increased life all week
• Decreased life next Monday
• Life in tanks are not stable
• Begin trying changing operations.

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Massive Colony of Stalked Ciliates
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EUPLOTES
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Biosolids

• Five years of study for class A EQ status
• Sent in application for certification
• Received certification
• Applied 1st time as Certified Class A EQ
• Emptied both biosolids tanks(800K 700K)

9
Point Source Study

• DEQ show up to do Point Source Study
• Everything appears to be normal
• Received a phone call on biosolids
• Sample of digester 1 to 2 transfer is Hot!
• Zinc Level shows 6010mg/L
• Are our numbers right?

10
Wet Test

• Sent in WET test sample to ASCI Lab.
• Before second sample get call
• Everything is dead in 100/66 samples
• What is happening
• Sodium thiosulfate remaining sample
• No die off.
• Heavy metal present.

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We have a problem

• Low bug populations
• High zinc level in Point Source biosolids
• Toxicity caused by heavy metal
• Better find out whats wrong

12
Confirm tests

• Do we have or had a problem?
• Start testing influent effluent daily
• Internal Testing lab.
• Test seven days a week
• Start testing Digester solids
• What for results to see what we will do.

13
Investigation

• We have a problem
• Start testing trunk lines plant
• Start testing industries on a more frequent
  basis.
• Two Isco Samplers plus Plant Sampler
• Hard to test and keep IPP program to date

14
Incoming Trunk Lines

• Four Trunk lines Converge at WWTP
• Able to test each line on plant ground
• Narrowed down to two trunk lines
• Investigated further- One trunk line now
• Our most Industrial trunk line.
• Also had Major county flow in it

15
Factories

• Many Industries on line plus county.
• Must eliminate one at a time. County first
• Military Pallets
• Rubber Factories
• Boat manufacture
• Power plant
• Foundry

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On the Trail of the Guilty

• Always Chasing tail
• Couldnt find guilty party
• Had Industry that was retrofitting Cooling tower
  at the correct time. Not guilty
• Only one industry never had a hit at plant while
  we were sampling it.
• Couldnt catch.

17
Sampling Trailer

• Sampling trailer Problem?
• Great deterrent
• Community Awareness
• Industry Tip Off ??

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Guilty Party

• Have idea who is guilty party cant prove
• Sampled 1 1/2 weeks straight no upsets
• Moved over weekend/Had upset
• Tested a week longer. No upsets
• Moved and then hid the sampler
• Had hot sample from industry
• Should have known it was the Foundry

19
The Meeting

• Called Industry about problem
• Set meeting date
• Found out they had been experimenting
• Oil cans and Soup cans
• pH in treatment system very low
• Kept zinc soluble
• Very hard on equipment

20
Results

• Never said the word Zinc
• Never admitted to wrong doing
• Offer to help pay for cleanup
• Doing this out of sense of community
• They would help us
• They were hoping we would help them
• Set up extra monitoring and limits

21
Toxic Sludge

• Now that problem taken care of what do we do with
  sludge.
• Store all in one tank
• Keep adding until level falls below ceiling
• Start filling second tank with Class B

22
Bidding

• Decided to put out to bid
• Six bidders
• Three within 8/10 of a cent
• One of low bidder was our own hauler
• Council went with Low bid
• Was an application not familiar with

23
Geotubes

• Fill tubes with sludge
• Add polymers
• Sludge will dewater
• Tubes will weep
• Add more sludge
• Repeat until tubes are filled
• Wait until dry

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Geotubes II

• Filled tubes
• Suppose to be 2 tubes
• Became 5 tubes
• Needed more polymer
• More space
• Time,time,time

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Flat Geotube
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Polymer
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Filling Geotube
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Weeping Geotube
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Disposal

• Never dried fully
• Add sawdust
• Take to landfill
• Increased landfill rates
• More cost and time
• Pleasantly surprised contractor stayed .

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Starting disposal
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Looks Messy
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Very Messy
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Outcome

• Be vigilant
• Test often
• Test on weekends
• Be prepared
• Work with industry
• Want to keep industry not drive away