HEADWORKS ANALYSES Tricks of the Trade

1
HEADWORKS ANALYSESTricks of the Trade

• Unknown Pretreatment Coordinator

2
HEADWORKS ANALYSES

• Background Information

3
Technically Based Local Limits

• Eleventh Commandment Thou
  Shalt Neither Covet Nor Steal Thy
  Neighbors Local Limits
• Keep in mind the definition of local site
  specificYOUR site
• Local limits should support and accommodate the
  strengths and weaknesses of each POTW

4
EPA Guidance Documents

• December 1987 Development and Implementation of
  Local Discharge Limitations Under the
  Pretreatment Program
• August 2001 - EPA Local Limits Development
  Guidance Draft
• Published in Final Version by End of Calendar
  Year 2003????

5
HWA/Local Limits Process

• Determine Pollutants of Concern
• Collect and Analyze POC Data
• Calculate AHLs for all POCs
• Select Most Stringent AHL as MAHL
• Determine MAIL
• Allocate MAIL to Industrial Users

6
HWA Data Used to

• Identify/confirm presence of pollutants
• Determine Pollutants of Concern POCs
• Determine current POTW loadings
• Calculate Removal Efficiencies
• Determine site-specific inhibition values
• Estimate loadings from IUs, domestic/
  uncontrollable sources, etc.

7
National Pollutants of Concern

• EPA Identified 15 pollutants often found in POTW
  effluent and sludge
• Assume all 15 to be POCs unless Approval
  Authority agrees otherwise
• EPA recommends POTW screening for these 15
  using data from
• POTW influent, effluent and sludge
• Industrial User discharges

8
National EPA POCs
Arsenic Lead Silver
Cadmium Mercury Zinc
Chromium Molybdenum BOD5
Copper Nickel TSS
Cyanide Selenium Ammonia
9
Actual Loading vs. MAHLsEPA Guidance

• Local limits should be established where
• The average actual influent loading of a
  pollutant is gt60 of the MAHL, or
• The maximum actual influent loading is gt80 of
  the MAHL any time in the 12 month period
  preceeding the analysis
• For BOD and TSS The monthly average influent
  loading is gt80 of design capacity
• any one month in the 12 months
  
• before the headworks analysis

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MAXIMUM ALLOWABLE HEADWORKS LOADING

• Removal Rate Math Formula
• Importance of Removal Rates

11
REMOVAL RATEMath Formula

• Removal Rate Efficiency
• Influent (mg/l) Effluent (mg/l) 100
• Influent (mg/l)

12
Calculate Removal Rate

• If a POTW has an influent BOD of 234 mg/l and
  an effluent BOD of 4.2 mg/l, what is the
  removal rate (efficiency)?
• 234 mg/l 4.2 mg/l 100
• 234 mg/l
• 
  98.2

13
Importance of Removal Rate Values

• Same POTW 15.0 mg/l NPDES BOD Limit
• 5.0 MGD Flow

RR MAHL lbs
92.4 8,215
93.4 9,466
94.4 11,176
95.4 13,594
RR MAHL lbs
96.4 17,389
97.4 24,061
98.4 39,115
99.4 104,250
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Importance of Removal Rate Values

• Same POTW 0.002 mg/l Cadmium Limit
• 5.0 MGD Flow

RR MAHL lbs
46.0 0.154
56.0 0.190
66.0 0.245
RR MAHL lbs
76.0 0.348
86.0 0.596
96.0 2.085
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TODAYS TRICKS

• HEADWORKS ANALYSIS SAMPLING
• HEADWORKS ANALYSIS ANALYSES
• DATA REVIEW and INTERPRETATION
• REMOVAL RATE DETERMINATION

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HEADWORKS ANALYSIS SAMPLING

• HWA Data vs. NPDES/DMR Data
• Paired Samples Detention Time Calculation
• Whole Effluent Toxicity

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HWA SAMPLINGHWA Data vs. NPDES Data

• NPDES Monitoring Daily Mon-Fri
• Consider Using all NPDES Data for HWA
• Composite Times of NPDES samples
• If only effluent analysis is NPDES required,
  look at resources for doing influent, too
• Dont sample on same day of week for every HWA
  sample Youll see why later
• Quarterly Sampling 5 yrs
• 20 data
  points

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HWA SAMPLING Know When NOT to Sample

• Hurricane or High Flow Conditions
• POTW Upset
• POTW Power Failure
• Equipment Break-Down or PM
• During POTW Upgrade/Expansion
• Holidays Week of Christmas/July 4th
• Dont be so compulsive that you cant be
  flexible with HWA sampling

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HWA SAMPLINGPOTW Sampling Locations

• POTW Influent
• Before mixing with any recycle streams
• POTW Effluent
• Aerobic/Anaerobic Digester
• Acclimation values
• Biosolids to Disposal
• 40 CFR Part 503 Annual Report Data
• Activated Sludge
• Acclimation values

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HWA SAMPLINGPaired Samples Sampling

• Pair Influent/Effluent Samples According to
  Detention Time (DT)
• Delayed Composite Samplers OR
• IF DT is 24 HOURS, or 48 HOURS, or 72 HOURS
• Just Use Regular Daily Composite
  Results and Match Them
• i.e. 24 hour DT Mondays influent is
• paired with Tuesdays effluent

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HWA SAMPLINGPaired Samples Sampling

• DETENTION TIME (DT) FORMULA
• POTW Detention Time in hours
• 24 hr/day POTW Tank Volumes MG
• Actual POTW Flow MGD

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Calculate Detention Time

• Tank Volumes look in POTW OM Manual
• Primary Clarifiers .40 MG
• Aeration Tanks 1.40 MG
• Final Clarifiers 0.60 MG
• Chlorine Contact Tank 0.105 MG
• Permitted Flow 4,000,000 gpd
• Actual Flow 2,250,000 gpd

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Calculate Detention Time DT

• TV 0.4 1.4 0.6 .105 2.505 MG
• Actual Flow 2,250,000 gpd
• 1,000,000 gal/MG 2.250
  MGD
• DT 24 (hr/day) Tank Volume MG
• Actual Flow MGD
• DT 24 (hr/day) 2.505 MG
• 2.250 MGD
• 26.72
  hours

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Calculate RR for Paired and Unpaired
Samples
My POTW DT is 72 Hours.So what????
DAY INF EFF RR
Fri
Mon 50 78
Fri
Mon 36 48
DAY INF EFF RR
Fri 325
Mon 78
Fri 294
Mon 48
-56
76
-33
84
MAHL 19.8 pounds Nickel
MAHL 0 pounds Nickel
POTW Flow 3.5 MGD NPDES Nickel Limit 136
ug/l
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HWA SAMPLINGWhole Effluent Toxicity

• Remember TWO 24-Hour Composite Samples Used For
  WET Bioassay
• Coordinate Quarterly HWA Analyses with Quarterly
  WET..
• Metals, Cyanide Influent and Effluent
• Influent Analyses on all POC
• Aeration Tank Samples for Inhibition, Too!!!

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HEADWORKS ANALYSIS ANALYSES

• Dont Go Changin..
• Metals, Metals Everywhere
• Trick or Treat????

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HEADWORKS ANALYSESDont Go Changin.

• Detection Limit (DL) a.k.a. Lower
  Reporting Level (LRL) a.k.a. Practical
  Quantitation Limit (PQL)
• What does this mean in a Commercial/POTW
  Laboratory?
• Trouble if you dont understand
• what you need and want.

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HEADWORKS ANALYSESMetals, Metals Everywhere

• REGULAR LEVEL METALS ANALYSES
• Flame Atomic Absorption AA
• ICP Plasma
• LOW LEVEL METALS ANALYSES
• Graphite Furnace Atomic Absorption
• ICP/MS Plasma Mass Spec

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Regular Level Metals Removal Rate Example

• Chromium Influent 11 ug/l
• Chromium Effluent lt10 ug/l
• Some states will let you use ½ DL on the effluent
  value.10 ½ 5 ug/l
• 11 5 100
• 11 54.5 RR
• OR Median Literature Value of 82
• VERSUS.

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Low Level Metals Removal Rate Example

• Same Exact HWA Samples analyzed by ICP-MS
• Chromium Influent 11 ug/l
• Chromium Effluent 0.70 ug/l
• 11 0.70 100 93.6 RR
• 11
• Oh what a difference ICP/MS makes!

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SAME POTWSAME SAMPLES.
5.0 MGD Flow and 0.050 mg/l Effluent Limit
Source/ Type of Metals Analysis Removal Rate Allowable Influent Chromium Chromium MAHL (pounds)
Regular Level 54.5 0.11 mg/l 4.6
Median Literature 82 0.28 mg/l 11.7
Low Level 93.6 0.78 mg/l 32.5
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Something Else to Consider

INF EFF RR
12.5 lt0.5 96.0
14.0 lt0.5 96.4
10.8 lt0.5 95.4
15.5 lt0.5 96.8
ADRE 96.15
INF EFF RR
12.5 lt0.1 99.2
14.0 lt0.1 99.3
10.8 lt0.1 99.1
15.5 lt0.1 99.4
ADRE 99.25
MAHL 7784 pounds NH3N
MAHL 1516 pounds NH3N
POTW Flow 3.5 MGD NPDES NH3-N Limit 2.0
mg/l
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HEADWORKS ANALYSES MercuryTrick or Treat?

• MERCURY Look out!!!
• Oregon Hg Stream Standard 0.012 ug/l 12 ng/l
• Many States previously had NPDES Permits with
  that limit and a 0.2 ug/l Quantitation Level
  Statement
• lt0.2 ug/l was considered compliant
• Cold Vapor AA LRL 0.2 ug/l 200 ng/l
• Method 1631 LRL 0.001 ug/l 1 ng/l
• Clean Metals Sampling is a MUST!
• Very few laboratories can perform this method
• Much more expensive

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HEADWORKS ANALYSES Cyanide Trick or Treat?

• CYANIDE TRICKS
• You Cant Teach an Old Method New Tricksat 5
  ug/l
• Split Samples and Matrix Spikes
• Before and After Chlorination
• Drinking Water
• Can a Hot Dog Manufacturer Really Have CN???
  Call the FDA!!!
• What are the Odds????

35
DATA REVIEW and INTERPRETATION

• HWA Data Review
• Signs/Causes of Trouble in Laboratory Land
• What Would You Do with this Mess?

36
HWA DATA REVIEW

• Review HWA Monitoring Plan Data
• Is the HWA Data Valid? Does it Make Sense?
• Is the Pollutant Present in the Influent?
• If not, can it be an internal POTW process?
• Is the POTW.Compliant? Noncompliant?
• Look at historical removal efficiencies
• How do they compare with what YOU got?
• Audit Laboratory POTW and Commercial

37
REVIEW HWA/HWA DATA ASAP

• HWA Cyanide Data Town X
• 22 Effluent CN Analyses in past 5 years
• 18 DP lt5 ug/l, 3 DP at 5 ug/l, 1 DP at 157 ug/l
• No Electroplating or Metal Finishing Facilities
• HWA Data-Same Date
• Influent CN 6.1 ug/l
• Primary Effluent CN lt5 ug/l
• Effluent CN 157 ug/l
• Youre in trouble if you havent even looked
• at the data until time to do HWA

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SIGNS OF TROUBLE IN LABORATORY LAND...

• Double Numbers
• Negative removal rates (maybe)
• Lots of Greater Than (gt) Values
• Metals, Metals Everywhere???
• TKN vs. Ammonia and NO2 vs. NO3
• COD vs. BOD
• What are the odds???

39
CAUSES OF TROUBLE IN LABORATORY LAND...

• Calculations units conversions, decimals
• Sample Mix-Up tough to trace
• Omission a preservative, a step, a
  reagent, BOD seed, pH adjustment
• Holding Time Exceedance
• Spill and Breakage
• Contamination

40
TROUBLESHOOTINGCorrect Units

• mg/l ppm milligrams per liter parts per
  million
• µg/l ppb micrograms per liter parts per
  billion
• ng/l ppt nanograms per liter parts per
  trillion
• Oregon Mercury Stream Standard
  chronic

mg/l ppm µg/l ppb ng/l ppt
1.0 mg/l 1000 µg/l 1,000,000 ng/l
0.010 mg/l 10 µg/l 10,000 ng/l
0.000012 mg/l 0.012 µg/l 12 ng/l
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The Troubles Youll See
Biosolids Analyses
Month Molybdenum Month Molybdenum
2-02 9.6 mg/kg 9-02 17.6 mg/kg
3-02 13.4 mg/kg 10-02 19.1 mg/kg
4-02 15.6 mg/kg 11-02 15.3 mg/kg
5-02 16.9 mg/kg 12-02 11.9 mg/kg
6-02 15.2 mg/kg 1-03 1110 mg/kg
7-02 24.4 mg/kg 2-03 12.4 mg/kg
8-02 27.9 mg/kg What are the odds???? What are the odds????
Calculation Error-Actual Value was 11.1
mg/kg Note 40 CFR Part 503 Ceiling Value is 75
mg/kg
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WHAT WOULD YOU DO WITH THIS MESS???

• Actual STMP Ammonia Values

Date Influent Effluent
2-20-01 lt 0.1 mg/l 1.9 mg/l
2-21-01 9.7 mg/l 0.8 mg/l
2-22-01 15.5 mg/l lt0.1 mg/l
2-23-01 8.8 mg/l 1.5 mg/l
From Commercial Laboratory, not POTW Laboratory
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WHAT WOULD YOU DO WITH THIS MESS??? 2
Actual STMP BOD Values
Date Influent Effluent
1-9-01 lt 2.0 mg/l lt2.0 mg/l
1-10-01 175 mg/l lt2.0 mg/l
1-11-01 256 mg/l lt2.0 mg/l
1-16-01 209 mg/l lt2.0 mg/l
From Commercial Laboratory, not POTW Laboratory
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REMOVAL RATE DETERMINATION

• EPA Local Limits Guidance Literature Values
• POTW Site-Specific Data Methods
• Review Data Set

45
Literature Removal Rates Median and
8th Decile Values

• Activated Sludge Treatment

EPA LLG MED 8th
Cadmium 67 91
Chromium 82 91
Copper 86 95
Lead 61 76
Mercury 60 79
EPA LLG MED 8th
Nickel 42 62
Selenium 50 67
Silver 75 88
Zinc 79 88
Cyanide 69 84
EPA Local Limits Development Guidance-Draft
8/2001
46
EPA Literature Values

• Avoid Them Like the Plague
• Generate Site Specific Data
• Based on POTW data from 1977!
• 2001 LL Guidance Draft Contains Same Outdated
  Data
• The Most Conservative Value Chosen in Every Case
  for Inhibition
• Domestic Values High in most cases

47
REMOVAL RATES POTW Site-Specific Data

• Average Daily Removal Efficiency ADRE
• Mean Removal Efficiency MRE
• Deciles

48
POTW Site-Specific RRAvg. Daily Removal
Efficiency

• Calculate daily removal efficiency DRE (removal
  rate) for each day you have influent and effluent
  data.and the influent value was detectable
• Average all the resulting DREs
• Can be used with paired or unpaired data EPA
  recommends paired

49
Calculate ADRE - BOD
Date Influent Effluent DRE
1-9-2001 lt2.0 mg/l lt2.0 mg/l
1-10-2001 175 mg/l lt2.0 mg/l
1-11-2001 256 mg/l lt2.0 mg/l
1-16-2001 209 mg/l lt2.0 mg/l
Using 0 Value Using 0 Value ADRE 1
Without 0 Value Without 0 Value ADRE 2
0.0
98.86
99.22
99.04
74.28
99.04
50
POTW Site-Specific RRMean Removal Efficiency
MRE

• Determine average of ALL influent values
• Determine average of ALL effluent values
• You may be able to use ½ DL for BDL
• Calculate removal efficiency using these two
  numbers
• Can be used with paired or unpaired samples

51
Calculate MRE - BOD
Date Influent Effluent MRE
1-9-2001 lt2.0 mg/l lt2.0 mg/l
1-10-2001 175 mg/l lt2.0 mg/l
1-11-2001 256 mg/l lt2.0 mg/l
1-16-2001 209 mg/l lt2.0 mg/l
Average 1
Average 2
161 mg/l
lt2.0 mg/l
98.76
lt2.0 mg/l
99.06
213 mg/l
1 With 1-9 Influent 2 Without 1-9 Influent
52
POTW Site-Specific RRCalculations Summary
Method Removal MAHL lbs
ADRE 1 74.28 2432
ADRE 2 99.04 65,156
MRE 1 98.76 50,444
MRE 2 99.06 66,543
15 mg/l NPDES BOD Limit 5.0 MGD Flow
53
POTW Site-Specific RRDeciles

• Requires at least 9 paired daily removal
  efficiency DRE values
• Sort DREs from highest to lowest and calculate
  the percentage of removal efficiencies above or
  below the specified removal efficiency

54
POTW Site-Specific RRDeciles

• Similar to a data set median but divides the data
  set into 10 equal parts
• 10 of the data is below the 1st decile, 20 is
  below the 2nd decile and so on
• The 5th decile data set median

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DECILES
Sample Set Influent Load (lbs) Effluent Load (lbs) DRE Deciles
5 230.10 9.79 95.75 9th90
1 51.82 11.14 78.50 8th80
4 173.99 47.44 72.73 7th70
7 47.32 13.27 71.96 6th60
9 30.67 13.27 56.73 5th50
8 31.42 14.90 52.58 4th40
6 17.05 10.51 38.36 3rd30
3 11.02 9.76 11.43 2nd20
2 16.40 17.39 -6.04 1st10
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CALCULATE ADRE
Sample Set Influent Load (lbs) Effluent Load (lbs) DRE ADRE
1 51.82 11.14 78.50
2 16.40 17.39 -6.04
3 11.02 9.76 11.43
4 173.99 47.44 72.73
5 230.10 9.79 95.75
6 17.05 10.51 38.36
7 47.32 13.27 71.96
8 31.42 14.90 52.58
9 30.67 13.27 56.73
44.44 ADRE
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CALCULATE MRE
Sample Set Influent Load (lbs) Effluent Load (lbs) DRE MRE
1 51.82 11.14 78.50
2 16.40 17.39 -6.04
3 11.02 9.76 11.43
4 173.99 47.44 72.73
5 230.10 9.79 95.75
6 17.05 10.51 38.36
7 47.32 13.27 71.96
8 31.42 14.90 52.58
9 30.67 13.27 56.73
67.75 16.39 75.81 MRE
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REVIEW DATA SET

• Review Data and Look for..
• Unusually low Daily Removal Efficiency
• Pattern of increasing effluent values with no
  similar influent increase
• Corresponding inf/eff extreme values
• CHECK YOUR MATH and computers math
• mg/l to ug/l conversions 0.0873 mg/l 87.3
  ug/l
• Paired Samples Review
• Will pairing make it better???

59
DATA EXCLUSION

• Technical or Operational Problems
• Fix it..then take extra HWA samples
• Influent BDL
• Must exclude for ADRE and Deciles
• Negative Daily Removal Efficiency
• Maybe.why?
• QA/QC Problems in the Lab
• Remember Metals, Metals Everywhere?
• Reanalyze if possible or Resample

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PICK THE NUMBER!!!!

• 98.43 or 98?
• 98.78 or 98.8?
• 1.062 lbs or 1.1 lbs?
• 95.5 or 96?
• 1.0467 lbs or 1.0 lbs?

61
Calculate the MAHL.Compare with Current
Loading.

• Are you are over-
• allocated???
• If so, you better
• start all over
• again!!!!!

EPA Region 10
U.P.T.C.
62
THE END!The Unknown Pretreatment
Coordinator can be reached in c/o
martie.groome_at_ci.greensboro.nc.us