Presentation by Chelsea Smith March 11, 2014. My Background Southern Wells (K-12) Graduated in 2010 Ball State University (2010-2014) BS in Environmental.

Presentation by Chelsea Smith March 11, 2014 My Background Southern Wells (K-12) Graduated in 2010 Ball State University ( ) BS in Environmental Management Minor in Criminal Justice Minor in Music Theory 2013 Summer Internship Salamonie Reservoir and Lake (DNR) Duties included: Assisting the Wastewater Treatment Operator Sampling drinking water Serving as a boat ramp attendant Lawn mowing and weed whacking Other Wastewater Treatment Plant Operations proceed 24/7 6 Stations Influent enters the plant (aka raw sewage) Main treatment (aka mixed liquor) Effluent exits the plant (aka final clear water) Lab tests occur at least once each week 1. Headworks/ Screen Unit Raw flows in Headworks: primary removal of large items before the water can be treated Screen unit removes debris and trash Leaves, toys, rocks, towels, Grit channel removes sand and smaller particles Purpose: To remove contaminants which improves later water treatment, making it more effective 2. Grease Separator Removes grease and oils from raw influent Purpose: To make water treatment more effective Grease may cause clogs It is difficult for microbes to digest grease = slow process 3. Chemical Feed Pump Treats water based of flow Ferric chloride (FeCl 3 ) Highly corrosive Low pH = Acidic Reddish-brown liquid (stains easily) Purpose: To remove sewage particles out of suspension in the water by coagulation Suspended particles attach to ferric salts and clump Clumps become bigger and heavier; settle to bottom 4. Clarifier (Main Treatment) Wastewater enters Aeration Tank Small air bubbles break up solids and mix water Microbes need oxygen to digest organic matter (sewage) Water moves from aeration tank to Clarifier Solids settle to the bottom of the Clarifier Sludge at bottom pumped to Sludge Holding Tank Clear water spills over Clarifier rings Purpose: To separate solids from clear water AND to digest organic compounds via microbial processes 5. UV Disinfection Clear water flows from clarifier into the UV basin Must move slowly = more retention time UV lights used instead of chlorine Cl harmful to aquatic life UV bulbs and basin must be kept clean Purpose: To kill any residual microorganisms and microbial pathogens (especially E. coli) 6. Final Aeration Basin Clear water moves through a flow meter and into the final basin Water cascades down many steps Discharged into the stream which flows into the lake Purpose: To improve oxygen content in the water, thus provided aquatic organisms with needed oxygen Wastewater Weekly Tests pH Dissolved Oxygen (DO) Carbonaceous Biological Oxygen Demand (BOD) Total Suspended Solids (TSS) Percent Settleable Solids in 30 minutes Ammonia Total Phosphorus E. coli pH pH probe inserted into 100 mL sample Stir rod helps give an accurate sample throughout Measures: amount of hydrogen ions in solution Importance: Aquatic organisms need pH 6-9 to survive Solution: Control amount of ferric acid added preparatorychemistry.com Dissolved Oxygen (DO) DO probe inserted into 100 mL sample Sensors must be fully submerged Measures: amount of oxygen molecules in water Importance: Aquatic organisms need DO levels above 5.0 mg/L to survive easily Solution: Increase aeration rate or allow sewage to have more retention time in aeration tanks Biological Oxygen Demand (BOD) 9 different bottles prepared and incubated for 5 days DO measured before and after incubation Measures: amount of oxygen needed for microbes to decompose the organic (carbonaceous) matter available in water Relates to DO levels (inverse reactions) Importance: Too much BOD can deplete DO levels Solution: Increase aeration rate and allow microbes to digest more organic matter Total Suspended Solids (TSS) Filter water sample through glass fiber filter and dry Weigh filters before and after sample is added Measures: amount of suspended solids in water Importance: Lower amount of suspended solids = lower turbidity of final clear water Solution: Increase retention time in aeration tank and increase amount of ferric acid added Settleable Solids in 30 minutes Let a 1000 mL mixed liquor sample settle solids for 30 minutes Level of solids at the bottom = % solids in water Measures: amount of larger solids in water that will settle to the bottom Importance: Microbes in the aeration tank need % solids for efficient and effective treatment Solution: Alter amount of solids (organic matter) in the aeration tank Ammonia Add water sample to prepared vials Use spectrophotometer to read ammonia levels after reaction completed Measures: amount of ammonia (NH3) molecules in the water Importance: Too much nitrogen in water can cause algae growth, which will deplete DO Solution: Increase aeration rates and retention time of mixed liquor in aeration basin Total Phosphorus Add water sample to prepared vials Use spectrophotometer to read phosphorus levels after reaction completed Measures: amount of phosphorus molecules in water Importance: High amounts can cause depletion of dissolved oxygen and lead to algae growth Solution: Increase addition of ferric acid to remove phosphorus by coagulation Spectrophotometer Escherichia coli Sample is poured into a tray with many wells After 24 hour incubation, number of luminescent wells correlates to amount of E. coli Measures: number of colony forming units (CFU) that are present in a 100 mL water sample Importance: E. coli is a disease-causing human pathogen Solution: Increase retention time in the UV basin and clean UV bulbs wikieducator.org Hazardous Materials Training Certified in HazMat Useful when dealing with chemicals (i.e. ferric acid) Weapons of Mass Destruction (WMDs) Class International and Domestic Terrorism Class lacountyfirefighters.org Level A PPE Level D PPE Any Questions? References pers/Technical%20Papers/Municipal-Odor-Control-Italy%20TP.pdfpers/Technical%20Papers/Municipal-Odor-Control-Italy%20TP.pdf tmentProcess.aspxtmentProcess.aspxfeatures/addressing-the-challenge.htmlfeatures/addressing-the-challenge.htmlcod-reduction/Pages/default.aspxcod-reduction/Pages/default.aspxhttps://engineering.purdue.edu/SafeWater/watershed/ecoli.html#levels