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  • Water Treatment ProcessesWater Treatment Plant Operation

    Florida Rural Water Association Water Treatment Plant Operation

  • Water Treatment ProcessesSection 1: Water Treatment ConcernsSection 2: Well ConsiderationsSection 3: Conventional Water System ProcessesSection 4: Disinfection By-Product ControlSection 5: Corrosion ControlSection 6: Demineralization ProcessesSection 7: Coagulation Process ControlSection 8: Water Softening

    Florida Rural Water Association Water Treatment Plant Operation

  • Section 1:Water Treatment ConcernsMicrobial Contamination ConcernsBarriers to Contaminants Reaching the PublicWhere Contamination Comes FromBacterial Indicators and PathogensPrimary Standards Secondary Standards

    Florida Rural Water Association Water Treatment Plant Operation

  • Microbial Contamination is Primary Concern of Water OperatorsColiform bacteria Common in the environment and are generally not harmful but their presence in drinking water indicates that the water may be contaminated and can cause disease.Fecal Coliform and E coli Bacteria whose presence indicates that the water may be contaminated with human or animal wastes. Microbes in these wastes can cause short-term effects, such as diarrhea, cramps, nausea, headaches, or other symptoms.Turbidity Has no health effects. However, turbidity can interfere with disinfection and provide a medium for organisms that include bacteria, viruses, and parasites that can cause symptoms such as nausea, cramps, diarrhea, and associated headaches.

    Florida Rural Water Association Water Treatment Plant Operation

  • Multiple Barrier ApproachSource: Selection and ProtectionTreatment: Methods and EfficienciesDistribution: Maintenance and Monitoring

    Florida Rural Water Association Water Treatment Plant Operation

  • Where Contamination Comes From* Multiple Sources, ie. runoff, septic tanks, CAFOs

    ConditionTest For:Reoccurring Gastro-illness*Coliform in Drinking WaterPipeline FailurepH, Lead, and CopperNearby AgricultureNitrates, Pesticides and ColiformNearby MiningMetals and pHNearby LandfillVOCs, TDS, Chlorides, & SulfateNearby Fueling VOCsBad Taste/OdorsHydrogen Sulfide and IronStains Clothes/PlumbingHydrogen Sulfide and IronScaly ResidueHardness

    Florida Rural Water Association Water Treatment Plant Operation

  • Microbial Contaminants found in Surface Water or UDI SourcesCryptosporidium and Giardia Parasites that enters lakes and rivers through sewage and animal waste. These typically cause mild gastrointestinal diseases. However, the disease can be severe or fatal for people with severely weakened immune systems. EPA and CDC have prepared advice for those with severely compromised immune systems who are concerned about these organisms.

    Florida Rural Water Association Water Treatment Plant Operation

  • Some Facts About BacteriaBacteria are widely distributed on earthThey have been found 4 miles above earth and 3 miles below sea sediments.One gram of fertile soil contains up to 100,000,000 bacteria. Bacteria are inconceivably small and measured in microns. One micron is equal to 1/1,000,000 of a meter.During the rapid growth phase bacteria undergo fission (cell division) about every 20 to 30 minutes.One bacterial cell after 36 hrs of uncontrolled growth, could fill approximately 200 dump trucks.

    Florida Rural Water Association Water Treatment Plant Operation

  • Bacteria and PathogenicIndicators in Water TreatmentPhoto: CDC. E. coli 0157:H711 of 140 cause gastrointestinal disease

    Total ColiformFermentLactose @ 35OCIncludeSpeciesof GeneraCitrobacterEnterobacterKlebsiellaE. ColiFecal ColiformGrow at 44OCProduce EnzymeE. ColiMore Specific Indicator of Contamination HPC< 500 colonies/ml

    Florida Rural Water Association Water Treatment Plant Operation

  • Identifying Source of Contaminants

    Florida Rural Water Association Water Treatment Plant Operation

  • Primary or Inorganic ContaminantsMineral-Based Compounds

    These include metals, nitrates, and asbestos. These contaminants are naturally-occurring in some water, but can also get into water through farming, chemical manufacturing, and other human activities. Potential health effects include learning disorders, kidney and liver damage. EPA has set legal limits on 15 inorganic contaminants.

    Florida Rural Water Association Water Treatment Plant Operation

  • Primary Standards and their Maximum Contaminant Levels (MCLs)

    ContaminantMCL (mg/l)Arsenic 0.010Asbestos 7 (MFL)Fluoride 4.0Mercury 0.002Nickel 0.1Nitrate10Nitrite 1Total Nitrate+Nitrite 10Sodium 160

    Florida Rural Water Association Water Treatment Plant Operation

  • Disinfectants and Disinfection By-ProductsDisinfectants are water additives that are used to control microbesDisinfection By-products are created when chlorine is added in the presence of naturally occurring low levels of organic materials found in drinking waterBoth are regulated because of health concerns

    Florida Rural Water Association Water Treatment Plant Operation

  • Secondary Standards and ConcernsThese compounds cause aesthetic concerns such as taste, odor and color. EPA recommends MCL limits Some states such as Florida have set regulatory limits on these contaminants

    Florida Rural Water Association Water Treatment Plant Operation

  • Secondary StandardMaximum Contaminant Levels

    Contaminant MCL (mg/l)

    Chloride250Sulfate250 TDS500 Copper1.0Fluoride2.0Iron0.30 Manganese0.05Silver0.1pH (MRCL)6.5 to 8.5Color (MCRL)15 cfu

    Florida Rural Water Association Water Treatment Plant Operation

  • Protecting Well by GroutingPrevent movement of water between aquifer formationsPreserve quality of producing zonesPreserve YieldPrevent water intrusion from surfaceProtect Casing against Corrosion!Pressure Testing of Grout Seal @ ~10 psi for 1 hr. Should be Performed.

    Florida Rural Water Association Water Treatment Plant Operation

  • Section 2Well ConsiderationsFloridan AquiferWell ContaminantsPreventing Contamination at the Well Head

    Florida Rural Water Association Water Treatment Plant Operation

  • Floridian Aquifer Across Florida

    Florida Rural Water Association Water Treatment Plant Operation

  • Well Source Water Parameters

    Quality and Quantity Dictates Depth of Well

    TDSTotal HardnessTotal Fe and MnChlorides & SulfatesTotal AlkalinityNitrate

    pHCorrosivityCO2H2SFluoride

    Florida Rural Water Association Water Treatment Plant Operation

  • Preventing Contamination at the Well Head

    #ObservationLikely Pathway1Septic tanks, broken storm or san. pipes, pondsThrough Surface Strata2Drainage up-hillSurface water runoff3Well subject to floodingSurface water transport of contaminants4Casing terminationMust be 1 and above 100 yr flood plane

  • Preventing Contamination at the Well Head (continued)

    #ObservationLikely Pathway5Area around well is wetCorroded Casing Pipe6Possible Abandoned wells in areaSurface water intrusion from contaminated source7Sanitary condition unacceptableContaminated water intrusion8Cracking in Well SlabContaminated water intrusion

    Florida Rural Water Association Water Treatment Plant Operation

  • Preventing Contamination at the Well Head (continued)

    #ObservationLikely Pathway9Evidence of Algae or Mold on SlabBirds and insects attracted by moist conditions10Poor DrainageSurface water intrusion from contaminated source11Seal water Draining into well headContaminated water entering borehole 12Well Seal damagedContaminated water intrusion

    Florida Rural Water Association Water Treatment Plant Operation

  • Preventing Contamination at the Well Head (continued)

    #ObservationLikely Pathway13Fittings pointing upwardContaminated Water intrusion into casing14Well vent not properly installedContaminated Water intrusion into casing15Check Valve absent or not workingContaminated water back-flowing into casing 16Cavitation or water hammerCk. Valve damage & water back-flowing into casing

    Florida Rural Water Association Water Treatment Plant Operation

  • Preventing Contamination at the Well Head (continued)

    #ObservationLikely Pathway17Well Site Security CompromisedContaminated Water from undesirable activities18Livestock or wild animals close byAnimal source of Contamination19Surface water evidence IDIndicator organisms, color, temp and TOC contributing20Several wells availableOne well is more likely to contribute than others

    Florida Rural Water Association Water Treatment Plant Operation

  • Preventing Contamination at the Well Head (continued)

    #ObservationLikely Pathway21Intermittent Well OperationContaminated occurring from long-term biological activity22Wet or extreme weather eventsContamination from run-off or from higher pumping levels.

    Florida Rural Water Association Water Treatment Plant Operation

  • Section 3:Conventional Water System ProcessesTOC in Source WaterDisinfection and Uses of ChlorineAeration and Aerator TypesIron and Hydrogen Sulfide ControlFiltrationSedimentation

    Florida Rural Water Association Water Treatment Plant Operation

  • Organic Carbon (TOC) in Natural Waters mg/l.1 .2 .5 1.0 2 5 10 20 50 100 200 500 1000Sea WaterGround WaterSurface WaterSwampWastewaterWastewater EffluentMean Surface Water 3.5

    Florida Rural Water Association Water Treatment Plant Operation

  • Disinfection with ChlorineThe primary methods of disinfection is the use of chlorine gas, chloramines, ozone, ultraviolet light, chlorine dioxide, and hypochlorite.Generally Chlorine will

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