EPA Steam Electric Study: DraftSAP, Draft CRC-ICP-MS SOP &UWAG CRC Split SampleConfirming Analysis StudyPresentation to the U.S. EPA Engineering andAnalysis DivisionWashington DC 3-11-2010Dr. Paul N. BootheAlbion EnvironmentalBryan, TX.Dr. Tom HigginsCH2M-HillChantilly, VADonna B. HillUtility Water Act Group& Southern Co.Understanding of GoalsGoals:•FGD wastewater characterization•Treatment performance (removal efficiency,effluent concentrations, pollutant loadings?)To help meet goals, EPA should build onwhat has been learned to dateFGD Wastewater Composition andTreatment Effectiveness Vary WidelyParticulate concentrations vary over minutes dueto batch operationsHydraulic residence time varies from 1 to 30 daysSoluble concentrations vary slowly over weeks ormonths•Due to factors including coal source, age of SCRcatalyst, changes in raw water supply, load, temperature,efficiency of ESP, etc.Treatment efficiency varies among plants usingsimilar treatment technologiesFGD WaterVaries OverTimeSignificant variationduring a year at a givenplantÆshort term(daily, weekly, monthly)data may notaccurately representtreatment systemperformance andeffluent qualityMercury Effluent00.511.522.533.5NJ F A J J SOD2008

Mercury (ug/L)TotalSolubleTreated FGD Wastewater VariesOver Time1101001000100001000001000000 Dec ‐ 0 8 Feb ‐ 09 Apr ‐ 09 J un ‐ 0 9 A u g ‐ 09 O ct ‐ 09 Dec ‐ 09

Mercury (ppt)FGDPurgePhys chemEffluentBiochemEffluentInfluent FGD Water VariesWithin and Among Plants1101001101001,000Metal020406080100

 Soluble Fraction (%) Soluble Fraction (%)FeAlBaCdSbCrAsCuHgSeBo0.1  ppb

 ppm Soluble ppm SolubleSoluble Mercury in TreatedFGD Water(Phys/Chem Precipitation)01002003004005006007008009001000 H G 3 H G 4 HG 12 L S2 BLSFO-3Site

Mercury (ng/L)Treatment Varies Among PlantsFGD water variesÆtreatment variesSome factors thataffect treatmentvariability•Biological Se removalaffected by nitrates•Metal precipitationaffected by organicsUse of Influent DataDrives Sampling ApproachCharacteristics of Influent•High solids content•Variable composition among batchesTo collect representative influent total metalsamples:•Grab sample at EQ tank or•Manual flow-weighted composite of the hydrocloneoverflow over a batchFor soluble metals analyses, grab samples fromeither point are adequate.Summary of RecommendationsIncrease:•More plants to characterize treatability•Separate samples by more than hydraulic residence time at each plantto measure variability accurately•Sample over different seasons•Add selenium speciation – important to treatability•Collect WWTP operating data (PFDs, chemical doses, etc)Decrease:•Number of samples per week•Use of automated composite samplers–EQ tank and Effluent tank provide good compositing•Analytes that are consistently low in concentration and are verydifficult to analyze (e.g.,Be, Ag, Pb, Sb, Sn, and Ti)Cyanide by EPA Method 335.4Concerned about the reliability of currentlyaccepted methods for analyzing cyanide in FGDwastewater•False positives resulting from cyanide formationduring sample storage at high pH have been reported(Anita Pandit, et al.)•False positives identified by Applied Speciation dueto presence of nitrates and nitrites in FGDwastewater (Jan. 2009)Set up SAP to allow for confirmation of falsepositivesHexavalent Chromium by EPAMethod 218.6Concerned about the reliability ofapproved methods for analyzing Cr+6 inFGD wastewater•Interferences with colorimetric methodsConfirm the detectable Cr+6 by validatingagainst the dissolved chromium values inthe same sampleEPA DRAFT CRC-ICP-MS SOPEPA-UWAG meeting 6-25-09 recommendation:•Develop and validate methods that consistentlyproduce acceptably accurate data in a variety of FGDwaste water matrices and that can be implementedwidely by the environmental testing laboratorycommunity.EPA draft SOP provides a good starting point toaddress this recommendation•Use of synthetic FGD wastewater a good idea–Should be used more widelyin SOP including carry throughdigestion with pre-digestion spike to optimize methodSOP Synthetic FGD Wastewaterversus CRC Study MeansElementSOP Synthetic FGDWastewater (ppm)CRC Split Sample StudyMeans (ppm)Boron350165Calcium50002900Chloride1500012600Bromide50Not MeasuredFluoride10Not MeasuredIron1001.7Magnesium40001360Manganese6048Sodium1000343Sulfate40002000EPA DRAFT CRC-ICP-MS SOPQuestions:•Was draft SOP method geared for high samplethroughput labs with minimal effort devoted toresolving matrix interferences identified?•Was a “slug type” sample loop discrete sampleintroduction system (e.g. Agilent ISIS-DS) used todevelop the draft SOP?•Were all split study samples analyzed undiluted byEPA’s contract lab (Test America, Arvada, CO)?DRAFT CRC-ICP-MS SOP(con’t)Need more information in SOP to facilitatemethod setup and implementation by labs•ISIS-DS specifications & setup parameters if used•HMI specifications & setup parameters if used•Instrument setup parameters–Plasma setup conditions–Collision cell setup parameters•No discussion of optimizing collision cell performance–Data acquisition parametersDRAFT CRC-ICP-MS SOP(con’t)Analytical concerns raised by the SOP•FGD samples run undiluted regardless of TDS–Assuming “standard” ISIS-DS setup (without HMI) TDS massloading up to twice that of analyzing FGD sample aliquotsdiluted to TDS < 2,000 ppm–Impact on CRC analyses interference control to be determined•30 second inter-sample rinse time may not be sufficient•SOP appears to quantify based on LDR not highcalibration standard–Such extrapolation with FGD matrices not optimalDRAFT CRC-ICP-MS SOP(con’t)Analytical concerns raised by the SOP(con’t)•Fixed concentration pre-digestion spikes meansunusable MS/MSD’s for higher concentrationelements such as selenium–Should pre-screen and adjust spiking levels•Failed MS/MSD’s only R-Flagged as matrix specificinterference suspected–Should require dilution and re-analysis–If MS/MSD still not pass data should be flagged as not usablefor compliance reporting purposes.DRAFT CRC-ICP-MS SOP(con’t)Other suggested additions to SOP•Alternate element masses and other masses to bemonitored to assess data quality not specified–Very important to facilitate this monitoring•Expand list of internal standard elements–Need statement that internal standards maybe present“naturally” in some FGD wastewaters•For example, scandium will bepresent in some FGD matrices–Need more recommended internalstandards (e.g. Rh, Ga, Bi)and statement on when and how to substituteDRAFT CRC-ICP-MS SOP(con’t)Clean analytical procedures similar to those inEPA method 1638 should be incorporated intothe SOP and emphasized as needed to achievelow detection limitsAluminum & zinc are the poster children for samplingcontaminationIdentifying and correcting interferences notcontrolled by CRC guidance should beexpanded (see section 2.4)Recommendations for FinalizingDraft SOPNeed joint sharing of CRC Split Sample Study datawithout compromising blind intercalibrationapproach•UWAG confirming analyses data important role invalidating efficacy of draft SOP CRC method•Follow-up meeting to share data, etc.•Additional analytical validation may be needed aftersharing split sample dataSOP needs considerable expansion to make iteasier to implement by typical laboratories•UWAG can provide a more detailed review of draft SOP inwritingUWAG CRC SPLIT SAMPLE STUDY:CONFIRMING ANALYSIS DATALacking FGD CRM’s, confirming analyses ofsplit sample data is the best way to objectivelyvalidate the accuracy of the data producedusing the EPA draft CRC-ICP-MS SOPSample collection•Quasi-conventional sampling procedures (gloves only)•All samples collected by local personnel (11-2009)–Following sampling instructions developed jointly by EPA &UWAG•“Multi-pour” splits- EPA bottles & UWAG carboysUWAG CRC SPLIT SAMPLE STUDY:CONFIRMING ANALYSIS DATA(con’t)UWAG split sample processing•Specific conductance pre-screening•‘Raw” sample “multi-pour” sub-sampling–Treat as dissolved samples•Preservation pH < 2 under clean room conditions•Four different total recoverable digestions•“Multi-pour” splits of appropriate digests sent toparticipating confirming analysis labs•Blind intercalibration–All labs diluted digestions prior to analysis to achieve TDS< 2,000 ppmSplit Sample Study Sampling PointsFacilitySampling PointsEstimated TDS (mg/L)AFGD InfluentBioreactor InfluentBioreactor Effluent14,60015,70015,300BFGD InfluentFGD Effluent12,30010,300CFGD InfluentFGD Effluent23,10016,500DFGD InfluentFGD Effluent27,70028,100EFGD InfluentFGD Effluent16,70025,400FFGD InfluentFGD Effluent14,70014,100GFGD InfluentFGD Effluent27,80025,900HFGD InfluentBioreactor InfluentBioreactor Effluent8,2407,3707,440IFGD InfluentFGD Effluent23,30021,400UWAG Multi-Digestion StudyDig.#DescriptionAcidsUsedDigest QASpikesSamplesDigestedLabsAnalyzing1Closed Vessel (EPA 1638)+ UV photo-oxidation (AEonly for HGAF)2% HNO32 DUP2 MS/MSDMethod BlkPost-DigestAll 20 splitsAll UWAG Labs2Open Vessel MinimalVolume Reduction (EPA200.2/ 200.8)1% HNO30.5% HCL1 DUP1 MS/MSDSRMBlank SPK3 M-BLKs2 Chk SPKsPre-Digest10 of 20 splitsDuke, AE3Diluted Open VesselMinimal Volume Reduction(EPA 200.2/ 200.8)1% HNO30.5% HCLSame as # 2except no DUP orMS/MSDNA4 of 20 splitsAE4Open Vessel 80% VolumeReduction (EPA 200.2/200.8)1% HNO30.5% HCL1 MSSRMBlank SPK2 M-BLKs2 Chk SPKsPre-Digest6 of 20 splitsAE5“Raw” Undigested (EPA200.8/1638)1% HNO32 DUP2 MS/MSD1 M-BLKPost-Digest20 of 20 splitsAEUWAG Confirming Analysis Labs & MethodsLaboratoryInstrument (s) UsedMethod(s) UsedCell Gases UsedDigests SplitsAnalyzedOhio State Univ.(TERL)Thermo HR ICP-MSHR-ICP-MSNot Appl.Closed (# 1)Albion Env.PE Elan DRC IIPSA Millenium (HGAF)EPA 200.8/1638 STDEPA 200.8/1638 (mod)EPA 1632 (mod)NoneNH3, O2Not Appl.All 5 DigestsApplied SpeciationPE Elan DRC IIEPA 200.8/1638 STDEPA 200.8/1638 (mod)NoneNH3, O2Closed (# 1)Southern Res. Inst.Agilent 7700EPA 200.8/1638 STDEPA 200.8/1638 (mod)NoneHe, HClosed (# 1)Duke EnergyAgilent 7500ICP-OESEPA 200.8/1638 STDEPA 200.8/1638 (mod)EPA 200.7NoneHe, HNot Appl.Closed (# 1)Open (# 2)UWAG Confirming Analysis ClosedVessel Data High Se SamplesIncreasing TDS ->UWAG Confirming Analysis ClosedVessel Data Low Se SamplesIncreasing TDS ->UWAG Confirming Analysis Open VesselData High Se SamplesIncreasing TDS ->UWAG Confirming Analysis Open VesselData Low Se SamplesIncreasing TDS ->FailedMS/MSDUWAG Lessons Learned from CRCSplit Sample StudyICP-OES selenium data (EPA 200.7) generallyagrees well with HR data except when closeto reporting limits•Robust 200.7 implementation good analyticalmethod for most metals in FGD wastewatersDRC Se data generally agrees with HR dataMost CRC Se data lower than benchmark HRdata by 20-25%•Still working on what this meansUWAG Lessons Learned from CRCSplit Sample StudyHGAF Se data generally lower than HR data•~ 10% and influenced by uv digestionInter-method variability increases with TDSDifferent digestion procedures generally notresult in significant metals data variability•Indication of volatile loss of Se in some FGDwastewater matrices in open digestions–Need to use matrix specific MS/MSD’s to identify–Not sure how widespread this effect may be–Closed vessel digestions safest approach