Appendices
Page
Appendix A
Local Limits Development Process Checklist
88
Appendix B
Bioconcentration Factors
92
Appendix C
Formulas used in local limits calculations
93
Appendix D
Method Detection Limits
95
Appendix E
How to Submit Modifications
96
Appendix F
National Recommended Water Quality Criteria: 2002
National Recommended Water Quality Criteria: Human
98
Health Criteria Calculation Matrix
Appendix G
Federal Sewage Sludge Standards
99
Appendix H
Toxicity Characteristic Leachate Procedure (TCLP)
Limitations
101
Appendix 1
Drinking Water Standards
103
Appendix J
Hauled Waste Loadings
108
Appendix K
Priority Pollutant Removal Efficiencies
109
Appendix L
Methods for Calculating Removal Efficiency
114
Appendix M
Specific Gravity of Sludge
123
Appendix N
Sludge AHL Equations Using Flow (in metric units)
125
Appendix 0
Closed-cup Flashpoints for Select Organic Compounds
127
Appendix P
Discharge Screening Levels and Henry=s Law Constants
for Select Organic Compounds
128
Appendix Q
OSHA, ACGIH and NIOSH Exposure Levels
131
87
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Appendix A
Local Limits Development Process Checklist
Preliminary Data
TASK
DONE
POTW highest Monthly Avg Flow (MGD)
The total of these flows should = total flow Domestic Flow (mgd)
Non-domestic flow (mgd)
Hauled Waste (mgd)
SIU Flow (mgd)
% Solids to Disposal
Biosolids Flow to Disposal (mgd)
Biosolids Disposal Site Area and Site Life
Density of Biosolids to Disposal
Influent Data
Effluent Data
Biosolids Data
Commercial Data
Domestic Data
fiet the Prtllrt\A/inn Infnrma+inn frnm NPnF5 Pormit and tho Fart ^hwt/Patinnab
Aauatic Life Uses
Desianated Uses
Hardness of Upstream Receivinq Water
Aauatic Life - acute Drotection low-flow d Q 301
Aauatic Life - chronic protection low-flow (7 Q 101
NPDES Permit Limits
Acute limits (metals and orqanicsl for Stream Seqment
Chronic Limits (metals and oroanicsl for Stream Seoment
Human Health Standards Applicable to the Stream Segment
Final MCL Criteria if Stream Segment or downstream stream segment is a drinking water supply
Process inhibition criteria (if needed for your POTW)
Biosolids Limits based upon disposal options
88
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Influent Scan
TASK
DONE
Has at least one influent scan been performed in the last 12 months that meet the criteria listed in Step 1 of this strategy?
Perform priority pollutant scan according to criteria in Step 1 of this strategy
Identify any pollutant from the influent priority pollutant scan that meet the criteria listed in Step 1 of this strategy.
Prior to eliminating a compound identified as a pollutant of concern seek approval from the Approval Authority
Generate a complete list of pollutants of concern
Is there enough data available for the determined POCs that no additional sampling is needed?
Development of Sampling Plan
TASK
DONE
Identification of needed sampling locations (e.g. influent, effluent, sludge, hauled waste, SlUs, receiving water,
commercial, domestic only) see Step 3 for details
Do your sampling locations meet all the criteria listed in Step 2 of this strategy
Parameters to be sampled at each location
Type of sample needed for each parameter (grab, composite, flow or time proportioned, etc)
Identification of containers, preservatives, holding times, and shipping/storage procedures for each parameter
ID of analytical methods and required MDL for analysis of each parameter
Date and number of samples to be collected at each location
POTW process hydraulic detention time between sampling at each location (for calculation of removal efficiencies)
Chain of Custody form for identification of data to be recorded for each sample
Sampling Program
TASK
DONE
All wastewater sampling and analysis must be done in accordance with the methods specified by 40 CFR Part 136
Sludge analyses must be in accordance with 40 CFR 503.8, or if not addressed in 503.8, with the latest edition of
"Biosolids Management Handbook..."
Collect at least six samples from each sampling location
Good sampling techniques used for all sampling (list of techniques in Step 3 of this strategy).
POTWs with a lagoon treatment system, see Step 3 of this strategy for special instructions
89
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Compiling Needed Information
TASK
DONE
Choose a method to handle BLD Data listed in Step 4 of this Strategy
Receiving Water Data: If data shows BDL, assume zero until data is generated showing presence
Biosolids Data: BDL Biosolids data should be reported as Vfe the MDL
Choose a removal efficiency calculation method for each pollutant of concern( see methods in Step 4)
Calculate removal efficiency for each pollutant of concern (see Appendix F)
Local Limits Calculation
Each pollutant of concern evaluated for applicable critera listed in Step 5 of this Strategy
Evaluation of Local Limits for Organics (see Step 5 of this strategy).
Evaluation of BTEX Local Limits (see Step 5 of this strategy).
Determination of Safety & Expansion factor (see guidance in Step 5 of this strategy).
Calculate local limits with Region 8 Local Limits Spreadsheet (see Step 5 of Strategy)
Develop a Local Limits for each POC
Arsenic, cadmium, chromium (total or III), chromium VI, copper, lead, mercury, molybdenum, nickel, selenium,
silver, and zinc local limits develoDed?
Any POC, based on current loadings, that meet the criteria in Section IV of the Strategy
Allocation of Pollutant Loadings
Determine allocation method to be used for each pollutant (see Step 5 and Step 7 of strategy for guidance)
Describe allocation method used for each pollutant (to be submitted with approval package)
List of each SIU and the mass of each POC that will be allocated to each user (for mass limits)
A description of the tracking/methodology to be used to show that MAILs are not exceeded
Review ordinance/rules and regulations language for MAILs in Step 7 of this strategy.
Review options for permit language concerning pollutant limits in Step 7 of this strategy.
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Local Limits Approval Package
Information requested in Appendix B
A simple schematic of POTW including treatment units, designation of treatment processes, sample locations for
influent, effluent, and biosolids
Initial influent scan and other data used to identify POC
A complete list of Pollutants of Concern
A statement that the POW has all chain of custody info on file and that the records will remain on file as long as the
current limits are in effect
Explanations for not developing a limit for a pollutant of concern
The Local Limits Spreadsheet (including any notes on data entered into spreadsheet)
Explanation of decisions that deviated from the Strategy
Explanation of abbreviations used on data sheets and in calculations
Draft Legal Authority language showing what will be changed
Calculated Local Limits
An attorney statement
Submission made by the authorized signatory official for the POTW
Any other data requested by the Approval Authority
MODIFICATION OF ORDINANCE/RULES
Local limits submittal approved
A modified ordinance that includes local limits
Description of process to be used to update any orders/permits
A timeline for implementation
Public Notice and comment period
Approval Authority approval or denial
91
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APPENDIX B
BIOCONCENTRATION FACTORS
BIOCONCENTRATION
POLLUTANT
FACTOR
acrolein
215
acenaohthene
242
4-bromoohenvl ohenvl ether
1640
butvlbenzvl ohthalate
414
2-chloronaDhthalene
202
4-chloroohenvl ohenvl ether
1200
3,3'-dichloro benzidine
312
fluroranthene
1150
hexachlorobenzene
8690
aldrin
4670
chlordane
14100
4.4'-DDT
53600
4.4'-DDE
53600
4.4'-DDD
53600
dieldrin
4670
aloha-endosulfan
270
beta-endosulfan
270
endosulfan sulfate
270
endrin
3970
endrin aldehvde
3970
heDtachlor
11200
heotachlor epoxide
11200
PCB-1242
31200
PCB-1254
31200
PCB-1221
31200
PCB-1232
31200
PCB-1248
31200
PCB-1260
31200
PCB-1016
31200
toxaohene
13100
Mercurv, Total
5500.3760. 9000
2,3,7,8-TCDD - Dioxin
5000
92
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APPENDIX C
Formula's Used in Local Limits Calculations
NPDFS PFRMIT CRITFRIA
(8.34) (Ccr it) (Qpotw)
Lin =
(1 -Rpotw)
where: Lin = Allowable headworks loading lbs/day
Ccrit = NPDES permit limit, mg/L
Qpotw = Highest monthly average POTWflow for past 12 months, MGD
Rpotw = Removal efficiency across POTW (USE DECIMAL)
WATER QUALITY CRITERIA
Water quality criteria represent in-stream concentrations that may not be exceeded in the
receiving stream. For metals, hardness correction is often needed (Table 1). The following
formulas are used for calculating maximum headworks loadings based on water quality criteria:
For chronic limits:
(8.34)[Ccwq(Qstr + Qpotw) - (CstrQstr)]
Lin/c =
(1 -Rpotw)
where: Lin/c = Allowable headworks loading based on chronic toxicity
standard, lbs/day
= Chronic water quality standard, mg/L
= Receiving steam flow, MGD (USE STREAM FLOW THAT IS
CONSISTENT WITH WHAT YOUR STATE WOULD USE FOR CHRONIC
CRITERIA) For example, some states specify a 30E3 for
chronic.
= Highest monthly average POTWflow for past 12 months,
MGD
= Background (upstream) pollutant concentration in
receiving stream, mg/L
Rpotw = Removal efficiency across POTW (USE DECIMAL)
Ccwo
Qstr
Qpotw
Cstr
93
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For acute limits:
(8.34)[Cawq(Qstr + Qpotw) - (CstrQstr)]
Lin/a =
(1 -Rpotw)
where: L|N/a = Allowable headworks loading based on acute toxicity
standard, lbs/day
= Acute waterquality standard, mg/L
= Receiving steam flow, MGD (USE STREAM FLOW THAT IS
CONSISTENT WITH WHAT YOUR STATE WOULD USE FOR ACUTE
CRITERIA) For example, some states specify a 1E3 for
acute.
= Monthly average POTWflow for past 12 months, MGD
= Background (upstream) pollutant concentration in
receiving stream, mg/L
Rpotw = Removal efficiency across POTW (USE DECIMAL)
Cawq
Qstr
Qpotw
Cstr
SAFFTY AND FXPANSION FACTORS
Maximum allowable industrial loadings are calculated by applying a safety/growth factor to the maximum allowable
headworks loading and subtracting the domestic/commercial contributions to the headworks. The formula is as
follows:
Lall = (I-SF)Lmahl - Ldom
where: Lall = Maximum allowable industrial loading,
lbs/day
SF = Safety/growth factor, decimal
Lmahl = Maximum allowable headworks loading
Ldom = Domestic/commercial wastewater
pollutant loading, lbs/day
94
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APPENDIX D
Table - MDLs (ug/l) for Wastewater Analytical Methods
Metal Flame Furnace ICP 1631 1632 1637 1638 1639 1640
As 1
2
1
53
0.003
Cd
5
0.1
4
0.0075
0.025
0.023
0.0024
Crm
50
1
7
Crflin
CrflV)
Cu
20
1
6
0.087
0.024
Pb
100
1
42
0.015
0.0081
Ha
0.2 2
0.00005
Mo
100
1
8
Ni
40
1
15
0.33
0.65
0.029
Se
2
2
75
0.45
0.83
Aa
10
0.2
7
0.029
Zn
5
0.05
2
0.14
0.14
1. Gaseous hydride method
2. Cold vapor technique
EPA may periodically update these values. It is recommended that the reader check for the
latest MDLs.
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APPENDIX E
PRETREATMENT PROGRAM MODIFICATIONS
REGION VIII GUIDANCE ON DEFINING AND PROCESSING APPROVED PROGRAM
MODIFICATIONS
USEPA - Region 8
Industrial Pretreatment Program
June 15,1999
EPA promulgated modifications to pretreatment program modification procedures (40 CFR Section
403.18) on July 17, 1997 (62 FR 38406). This regulation also modified other Sections of 40 CFR Part 403 that
relate to approved POTW pretreatment program modifications. The proposed regulations were public noticed on
July 30, 1996 (61 FR 39804). This Guidance summarizes those changes and provides guidance to Approval
Authorities and Control Authorities on implementation of the modified rules.
In general, the modified regulation revised what types of program changes are considered to be
substantial, how public notices are to be performed, and a new procedure for non-substantial modifications.
SURSTANTIAI MODIFICATIONS
The following program changes are considered substantial modifications:
- Modifications that relax POTW legal authorities unless the modifications directly reflect revisions to Part 403;
- Modifications that relax local limits, except modifications of pH to the pH 5 minimum or reallocations of MAILs;
- Changes to the type or form of control mechanism used by the POTW for SlUs (e.g. order vs permit);
- A decrease in the frequency of self-monitoring or reporting for industrial users (general policy or approved
program);
- A decrease in the frequency of industrial user inspections or sampling by the POTW (general policy or approved
program);
- Changes to the POTWs confidentiality procedures;
- Any other modification that the Approval Authority deems substantial.
96
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All substantial modifications shall be submitted to the Approval Authority. The submittal should include all of the
following:
1. A statement of basis for the proposed modification;
2. An attorney's statement confirming that the modified legal authority will comply with the requirements of
local law, including complying with state and local law, regarding review and adoption by the Control
Authority of the new/modified legal authority. The attorney's statement shall also confirm that the changes
will not result in the POTW being in violation of its NPDES permit;
3. A copy of the draft legal authority that shows additions (by means of CAPITALIZATION AND BOLDING
and deletions by means of STRIKCTIIROUGI IS AND BOLDING at a minimum;
4. A copy of the draft legal authority showing all changes as they will look in final format;
5. A copy of the new forms/procedures affected by this modification;
6. Any other documentation required by the Approval Authority.
Substantial modifications shall be public noticed for comment in a paper of general circulation. No further public
notice is required if the original public notice provides for only one public notice AND no comments are received
AND the requested modification can be approved without change. The public notice may be performed by the
POTW if the Approval Authority agrees AND the public notice language is approved by the Approval Authority.
The decision on what party will perform the actual public notice is decided by the Approval Authority. The
Approval Authority is responsible for all public notices in any case.
All substantial and non-substantial modifications approved in accordance with 40 CFR Section 403.18 become
enforceable conditions of the POTWs NPDES permit (40 CFR Section 122.63(g)).
97
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Appendix F
National Recommended Water Quality Criteria: 2002
USEPA - OW
EPA-822-R-02-047
National Recommended Water Quality Criteria: 2002
Human Health Criteria Calculation Matrix
USEPA-OW
EPA -822-R-02-012
Documents from the Office of Water can be accessed at: http://yosemite.epa qov/water/owrccataloq.nsf/
98
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Appendix G - Federal Sewage Sludge Standards
Biosolids Land Application Limitations
Ceiling Concentration*
(Table 1,40 CFR 503.13)
Monthly Average Pollutant
Concentration*
(Table 3, 40 CFR 503.13)
Cumulative Pollutant Loading
Rates*
(Table 2, 40 CFR 503.13)
Annual Pollutant Loading
Rate*
(Table 4, 40 CFR 503.13)
Pollutant
mg/kg
lbs/1000 lbs
mg/kg
lbs/1000 lbs
kg/hectare
lbs/acre**
kg/hectare/
365-day period
lbs/acre/
365-day
period**
Arsenic
75
75
41
41
41
37
2
1.8
Cadmium
85
85
39
39
39
35
1.9
1.7
Copper
4,300
4,300
1,500
1,500
1,500
1,338
75
67
Lead
840
840
300
300
300
268
15
13
Mercury
57
57
17
17
17
15
0.85
0.76
Molybdenum
75
75
-
-
-
-
-
-
Nickel
420
420
420
420
420
375
21
19
Selenium
100
100
100
100
100
89
5
4.5
Zinc
7,500
7,500
2,800
2,800
2,800
2,498
140
125
* Dry weight.
** Calculated using metric standards specified in 40 CFR 503.13 multiplied by the conversion factor of 0.8922.
Source: 40 CFR §503.13, Tables 1-4, October 25, 1995
99
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Surface Disposal
Distance from the Boundary of
Active Biosolids Unit to Surface
Disposal Site Property Line
(meters)
Pollutant Concentration*
Arsenic
(mg/kg)
Chromium
(mg/kg)
Nickel
(mg/kg)
0 to less than 25
30
200
210
25 to less than 50
34
220
240
50 to less than 75
39
260
270
75 to less than 100
46
300
320
100 to less than 125
53
360
390
125 to less than 150
62
450
420
Equal to or greater than 150
73
600
420
* Dry-weight.
Source: 40 CFR Part 503
Conversion Factors
pounds per acre (lbs/ac) x 1.121 = kilograms per hectare (kg/ha)
kilograms per hectare (kg/ha) x 0.8922 = pounds per acre (lbs/ac)
pound (lb) = 0.4536 kilogram (kg)
kilogram (kg) = 2.205 pounds (lbs)
English ton = 0.9072 metric tonne
metric tonne = 1.102 English ton
100
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Appendix H - Toxicity Characteristic Leachate
Procedure (TCLP) Limitations
EPA Hazardous
Waste No.
Contaminant
CAS No.1
Regulatory Level (mg/L)
D004
Arsenic
7440-38-2
5.0
D005
Barium
7440-39-3
100.0
D018
Benzene
71-43-2
0.5
D006
Cadmium
7440-43-9
1.0
D019
Carbon tetrachloride
56-23-5
0.5
D020
Chlordane
57-74-9
0.03
D021
Chlorobenzene
108-90-7
100.0
D022
Chloroform
67-66-3
6.0
D007
Chromium
7440-47-3
5.0
D024
o-Cresol
95-48-7
2200.0
D024
m-Cresol
108-39-4
2200.0
D025
p-Cresol
106-44-5
2200.0
D026
Cresols
2200.0
D016
2,4-D
94-75-7
10.0
D027
1,4-Dichlorobenzene
106-46-7
7.5
D028
1,2-Dichloroethane
107-06-2
0.5
D029
1,1 -Dichloroethylene
75-35-4
0.7
D030
2,4-Dinitrotoluene
121-14-2
30.13
D012
Endrin
72-20-8
0.02
D031
Heptachlor (and its
epoxide)
76-44-8
0.008
D032
Hexachlorobenzene
118-74-1
30.13
D033
Hexachlorobutadiene
87-68-3
0.5
D034
Hexachloroethane
67-72-1
3.0
D008
Lead
7439-92-1
5.0
D013
Lindane
58-89-9
0.4
D009
Mercury
7439-97-6
0.2
D014
Methoxychlor
72-43-5
10.0
D035
Methyl ethyl ketone
78-93-3
200.0
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EPA Hazardous
Waste No.
Contaminant
CAS No.1
Regulatory Level (mg/L)
EPA Hazardous
Waste No.
Contaminant
CAS No.1
Regulatory Level (mg/L)
D036
Nitrobenzene
98-95-3
2.0
D037
Pentachlorophenol
87-86-5
100.0
D038
Pyridine
110-86-1
35.0
D010
Selenium
7782-49-2
1.0
D011
Silver
7440-22-4
5.0
D039
Tetrachloroethylene
127-18-4
0.7
D015
Toxaphene
8001-35-2
0.5
D040
Trichloroethylene
79-01-6
0.5
D041
2,4,5-Trichlorophenol
95-95-4
400.0
D042
2,4,6-Trichlorophenol
88-06-2
2.0
D017
2,4,5-TP (Silvex)
93-72-1
1.0
D043
Vinyl chloride
75-01-4
0.2
1 Chemical abstracts service number.
2 If o-, m-, and p-Cresol concentrations cannot be differentiated, the total cresol (D026)
concentration is used. The regulatory level of total cresol is 200 mg/1.
3 Quantitation limit is greater than the calculated regulatory level. The quantitation limit therefore
becomes the regulatory level.
Source: 40 CFR 261.24, August 31, 1993.
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Appendix I - Drinking Water Standards
National Primary Drinking Water Regulations
Contaminants
Maximum Contaminant
Level Goal (MGLC)
in mg/L
Maximum Contaminant Level
(MCL)
in mg/L
INORGANICS
Antimony
0.006
0.006
Arsenic
none
0.05
Asbestos
7 MFL*
7 MFL
Barium
2
2
Beryllium
0.004
0.004
Cadmium
0.005
0.005
Chromium (total)
0.1
0.1
Copper
1.3
Action Level=1.3
Cyanide (as free cyanide)
0.2
0.2
Fluoride
4.0
4.0
Lead
zero
Action Level=0.015
Inorganic Mercury
0.002
0.002
Nitrate (as Nitrogen)
10
10
Nitrite (as Nitrogen)
1
1
Selenium
0.05
0.05
Thallium
0.0005
0.002
Acrylamide
zero
**
Alachlor
zero
0.002
Atrazine
0.003
0.003
Benzene
zero
0.005
Benzo(a)pyrene
zero
0.0002
Carbofuran
0.04
0.04
Carbon tetrachloride
zero
0.005
Chlordane
zero
0.002
Chlorobenzene
0.1
0.1
2,4-D
0.07
0.07
Dalapon
0.2
0.2
l,2-Dibromo-3-chloropropane
(DBCP)
zero
0.0002
o-Dichlorobenzene
0.6
0.6
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Contaminants
Maximum Contaminant
Level Goal (MGLC)
in mg/L
Maximum Contaminant Level
(MCL)
in mg/L
p-Dichlorobenzene
0.075
0.075
1,2-Dichloroethane
zero
0.005
1-1-Dichloroethylene
0.007
0.007
cis-1,2-Dichloroethylene
0.07
0.07
trans-l,2-Dichloroethylene
0.1
0.1
Dichloromethane
zero
0.005
1-2-Dichloropropane
zero
0.005
Di(2-ethylhexyl)adipate
0.4
0.4
Di(2-ethylhexyl)phthalate
zero
0.006
Dinoseb
0.007
0.007
Dioxin (2,3,7,8-TCDD)
zero
0.00000003
Diquat
0.02
0.02
Endothall
0.1
0.1
Endrin
0.002
0.002
Epichlorohydrin
zero
•ft "ft "ft
Ethylbenzene
0.7
0.7
Ethylene dibromide
zero
0.00005
Glyphosate
0.7
0.7
Heptachlor
zero
0.0004
Heptachlor epoxide
zero
0.0002
Hexachlorobenzene
zero
0.001
Hexachlorocyclopentadiene
0.05
0.05
Lindane
0.0002
0.0002
Methoxychlor
0.04
0.04
Oxamyl (Vydate)
0.2
0.2
Polychlorinated biphenyls (PCBs)
zero
0.0005
Pentachlorophenol
zero
0.001
Picloram
0.5
0.5
Simazine
0.004
0.004
Styrene
0.1
0.1
Tetrachloroethylene
zero
0.005
Toluene
1
1
Total Trihalomethanes (TTHMs)
none
0.10
Toxaphene
zero
0.003
2,4,5-TP (Silvex)
0.05
0.05
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Contaminants
Maximum Contaminant
Level Goal (MGLC)
in mg/L
Maximum Contaminant Level
(MCL)
in mg/L
1,2,4-Trichlorobenzene
0.07
0.07
1,1,1-T richloroethane
0.20
0.2
1,1,2-T richloroethane
0.003
0.005
T richloroethylene
zero
0.005
Vinyl chloride
zero
0.002
Xylenes (total)
10
10
* Million fibers per liter, longer than 10 micrometers (//m) in length.
** Not to exceed 0.05% dosed at 1 ppm (or equivalent).
*** Not to exceed 0.01% dosed at 20 ppm (or equivalent).
Source: 40 CFR Part 141, National Primary Drinking Water Regulations and
http://www.epa.gnv/safewater/mfl.html
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National Primary Drinking Water Regulations
Disinfection Byproduct
Maximum Contaminant
Level Goal (MGLC)
in mg/L
Maximum Contaminant
Level (MCL)
in mg/L
Total Trihalomethanes*
_
0.080
Bromodichloromethane
zero
_
Dibromochloromethane
0.06
_
Tribromomethane (Bromoform)
zero
_
Trichloromethane (Chloroform)
zero
_
Haloacetic Acids (HAA5)**
_
0.060
Dichloroacetic Acid
zero
_
Trichloroacetic Acid
0.3
_
Bromate
zero
0.010
Chlorite
0.8
1.0
* Sum of the concentrations of Bromodichloromethane, Dibromochloromethane,
Tribromomethane, and Trichloromethane.
** Sum of the concentrations of Dichloroacetic acid, Trichloroacetic acid, Monochloroacetic
acid, Monobromoacetic acid, and Dibromoacetic acid.
Disinfectant Residual
Maximum Residual
Disinfection Level Goal
(MRDLG) in mg/L
Maximum Residual
Disinfection Level (MRDL)
in mg/L
Chlorine (as Cl2)
4
4
Chloramines (as Ch)
4
4
Chlorine dioxide (as CIO2)
0.8
0.8
Source: National Primary Drinking Water Regulations: Disinfectants and Disinfection
Byproducts (also known as the Stage 1 Disinfection Byproducts Rule - DBPR); 63
FR, December 16,1998, p 69389.
106
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National Secondary Drinking Water Regulations
Contaminant
Secondary Standard
Aluminum
0.05 to 0.2 mg/L
Chloride
250 mg/L
Color
15 (color units)
Copper
1.0 mg/L
Corrosivity
noncorrosive
Fluoride
2.0 mg/L
Foaming Agents
0.5 mg/L
Iron
0.3 mg/L
Manganese
0.05 mg/L
Odor
3 threshold odor number
PH
6.5-8.5
Silver
0.10 mg/L
Sulfate
250 mg/L
Total Dissolved Solids
500 mg/L
Zinc
5 mg/L
Source: 40 CFR Part 143, National Secondary Drinking Water Regulations;
http://www.epa.gov/safewater/mcl.html.
107
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Appendix J - Hauled Waste Loadings
SEPTA
GE HAULER MONITOR!]
\G DATA
Pollutant
Number of
Detections
Number of
Samples
Minimum
Concentration
(mg/L)
Maximum
Concentration
(mg/L)
Average
Concentration
(mg/L)
INORGANICS
Arsenic
144
145
0
3.5
0.141
Barium
128
128
0.002
202
5.758
Cadmium
825
1097
0.005
8.1
0.097
Chromium (T)
931
1019
0.01
34
0.49
Cobalt
16
32
< 0.003
3.45
0.406
Copper
963
971
0.01
260.9
4.835
Cyanide
575
577
0.001
1.53
0.469
Iron
464
464
0.2
2740
39.287
Lead
962
1067
<0.025
118
1.21
Manganese
5
5
0.55
17.05
6.088
Mercury
582
703
0.0001
0.742
0.005
Nickel
813
1030
0.01
37
0.526
Silver
237
272
< 0.003
5
0.099
Tin
11
25
<015
1
0.076
Zinc
959
967
<0.001
444
9.971
NONCONVENTIONALS
COD
183
183
510
117500
21247.951
ORGANICS
Acetone
118
118
0
210
10.588
Benzene
112
112
0.005
3.1
0.062
Ethylbenzene
115
115
0.005
1.7
0.067
Isopropyl Alcohol
117
117
1
391
14.055
Methyl Alcohol
117
117
1
396
15.84
Methyl Ethyl Ketone
115
115
1
240
3.65
Methylene Chloride
115
115
0.005
2.2
0.101
Toluene
113
113
0.005
1.95
0.17
Xylene
87
87
0.005
0.72
0.051
Source: U.S. EPA's Supplemental Manual on the Development and Implementation of Local Discharge
Limitations Under the Pretreatment Programs, 21W-4002, May 1991, pp. 1-27 and 1-28.
108
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Appendix K - Priority Pollutant Removal Efficiencies
PRIORITY POLLUTANT REMOVAL EFFICIENCIES THROUGH
ACTIVATED SLUDGE TREATMENT*
Prioritv Pollutant
Range
Median
# of
POTWs
METALS/NONMETAL INORGANICS
Arsenic
11-78
49
12
Cadmium
25-99
64
25
Chromium
25-97
77
28
Copper
2-99
86
35
Cyanide
3-99
69
25
Lead
1-92
63
29
Mercury
1-95
62
25
Molybdenum
6-71
29
6
Nickel
2-99
40
31
Selenium
25-89
48
10
Silver
17-95
77
31
Zinc
23-99
73
35
ORGANIC S
Anthracene
29-99
67
5
Benzene
25-99
80
18
Chloroform
17-99
67
24
1,2-trans-Dichloroethylene
17-99
67
17
Ethylbenzene
25-99
86
25
Methylene chloride
2-99
62
26
Naphthalene
25-98
78
16
Phenanthrene
29-99
68
6
Phenol
3-99
90
19
Bis (2-ethylhexyl) phthalate
17-99
72
25
Butyl benzyl phthalate
25-99
67
16
Di-n-butyl phthalate
11-97
64
19
Diethyl phthalate
17-98
62
15
Pyrene
73-95
86
2
T etrachloroethylene
15-99
80
26
Toluene
25-99
93
26
1.1.1 -T richloroethane
18-99
85
23
T richloroethylene
20-99
89
25
Source: Region 8 POTWs and U.S. EPA's Guidance Manual on the Development and Implementation of Local
Discharger Limitations Under the Pretreatment Program, December 1987, p. 3-56.
109
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TRICKLING FILTER
TREATMENT*
Range
Median
# of POTWs
METALS/NONMETAL INORGANICS
Arsenic
42
42
1
Cadmium
33-96
68
10
Chromium
5-92
60
16
Copper
12-97
60
14
Cvanide
7-88
59
8
Lead
4-84
62
10
Mercurv
14-80
65
13
Molybdenum
7-50
23
3
Nickel
7-72
41
13
Selenium
40-63
52
3
Silver
11-93
68
12
Zinc
14-90
63
14
ORGANIC S
Benzene
5-98
75
7
Chloroform
21-94
73
9
1,2-trans-Dichloroethvlene
14-99
50
7
Ethvlbenzene
45-97
80
10
Methylene chloride
5-98
70
10
Naphthalene
33-93
71
6
Phenol
50-99
84
8
Bis (2-ethvlhexvF) phthalate
4-98
58
10
Butvl benzvl phthalate
25-90
60
9
Di-n-butvl phthalate
29-97
60
10
Diethyl phthalate
17-75
57
8
T etrachloroethvlene
26-99
80
10
Toluene
17-99
93
10
1.1.1 -T richloroethane
23-99
89
10
T richloroethy lene
50-99
94
10
Source: EPA Region 8 POTWs and U.S. EPA's Guidance Manual on the Development and Implementation of Local Discharger
Limitations Under the Pretreatment Program, December 1987, p. 3-57.
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LAGOON TREATMENT
Range
Mean
# of POTWs
METALS/NONMETAL INORGANICS
Arsenic
Cadmium
Chromium
21
1
Copper
59-71
65
2
Lead
91
1
Mercurv
95
1
Molybdenum
75
1
Nickel
42
1
Selenium
77
1
Silver
76
1
Zinc
81-86
83
2
Source: EPA Region 8 POTWs
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PRIORITY POLLUTANT REMOVAL EFFICIENCIES THROUGH
TERTIARY TREATMENT*
Priority Pollutant
Range
Median |# of POTWs
METAL S/NONMETAL INORGANICS
Cadmium
33-81
50
3
Chromium
22-93
72
4
Copper
8-99
85
4
Cyanide
20-93
66
4
Lead
4-86
52
3
Mercury
33-79
67
4
Nickel
4-78
17
3
Silver
27-87
62
3
Zinc
1-90
78
4
ORGANIC S
Benzene
5-67
50
2
Chloroform
16-75
53
3
1,2-trans-Dichloroethylene
50-96
83
2
Ethylbenzene
65-95
89
3
Methylene Chloride
11-96
57
4
Naphthalene
25-94
73
3
Phenol
33-98
88
4
Bis (2-ethylhexyl) phthalate
45-98
76
4
Butyl benzyl phthalate
25-94
63
4
Di-n-butyl phthalate
14-84
50
4
Diethyl phthalate
20-57
38
3
T etrachloroethy lene
67-98
91
4
Toluene
50-99
94
4
1,1,1 -T richloroethane
50-98
94
4
T richloroethy lene
50-99
93
4
Source: EPA Region 8 POTWs and U.S. EPA's Guidance Manual on the Development and Implementation of Local Discharger
Limitations Under the Pretreatment Program, December 1987, p. 3-58.
112
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AVERAGE POTW REMOVAL EFFICIENCIES IN THE 47-POTW DATA BASE
Priority Pollutant
Median
Mean
Number
of POTWs
Barium
72.6115
72.6115
1
Cadmium
27.7778
-167.977
7
Chromium
68.1062
53.7813
10
Copper
65.100
58.462
25
Cyanide
18.1495
-2.4338
3
1,4-Dichlorobenzene
-93.6364
-93.6364
1
1,2-Trans-Dichloroethylene
85.7793
85.7793
1
Lead
45.1846
46.9904
12
Mercury
-3.1445
-3.1445
2
Nickel
33.9382
30.4551
10
Phenols
64.2493
61.0084
9
Bis (2-Ethylhexyl) Phthalate
26.3314
14.5997
7
Di-N-Butyl Phthalate
51.6304
51.6304
1
Di-N-Octyl Phthalate
78.0461
78.0461
2
Diethyl Phthalate
69.8795
44.7419
3
Silver
40.8160
46.9391
4
T richloroethylene
96.8850
96.8850
1
Zinc
62.0314
59.0255
27
Source: U.S.EPA's National Pretreatment Program Report to Congress, July 1991, p. 4-28.
113
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Appendix L - Methods for Calculating
Removal Efficiency
There are three methods of calculating removal efficiencies: average daily removal efficiency (ADRE)
method, mean removal efficiency (MRE) method, and the decile approach. Each of these methods uses a
set of influent and effluent values, and the concept of a daily removal efficiency (DRE). A DRE, expressed
PRE - 100 * {,nfllie'U -
Influent
as a percent, is calculated as:
Where:
Influent =Either the influent concentration from a daily sample, or the influent loading (calculated by
multiplying the same influent concentration by the daily flow and an 8.34 unit conversion
factor)
Effluent =Either the effluent concentration from a daily sample, or the effluent loading (calculated by
multiplying the same effluent concentration by the daily flow and an 8.34 unit conversion
factor).
The POTW may use either concentrations for both influent and effluent, or loadings for both.
It is important to realize that the portion of the pollutant removed through a treatment process is transferred
to another wastestream, typically the sludge. For conservative pollutants, such as metals, all the pollutant
from the influent ends up in either the effluent or the sludge. For example, a 93% overall plant removal
means that 93% of the cadmium in the influent is transferred to the sludge, while 7% remains in the
effluent wastewater.
1.REVIEW OF THE DATA SET AND EXCLUSION OF CERTAIN DATA
A good first step in determining removal efficiencies is to review the data set. This review can identify any
data values that are extremely high or low. If there are isolated extreme values, there are formal statistical
procedures that can be applied to evaluate whether a value can be classified as an "outlier" relative to the
rest of the data set. Two methods most widely used to make this determination are described in the
following two paragraphs.
If the data is known to closely follow a normal distribution, then any data point that lies more than two
standard deviations from the mean is considered an outlier. Consider, for example, the DRE data values
from located in Table 1 of this appendix, and assume that this data is from a normal distribution. The 15
observations have a mean of 52.69 and a standard deviation of 34.65. Using this method, any data point
that lies outside of the range -16.61 to 121.99, or 52.69J; 2*34.65, can be considered an outlier. In this
case, one value, -20.25, falls outside of the range and can be determined to be an outlier.
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If the data does not closely follow a normal distribution, outliers can be determined based on the
interquartile range (IQR) of the data set. First, order the data from smallest to largest and locate the data
points that fall at the 25th percentile (also referred to as the first quartile or Ql), and the 75th percentile (also
referred to as the third quartile or Q3). The IQR is equal to the value of the observation at Q3 minus the
value of the observation at Ql. Any data point that lies more than 1.5 times this IQR below Ql, or above
Q3, is considered an outlier. Again, consider the data in Table 1, but now make no assumptions about the
distribution of the population from which the sample was taken. The Ql and Q3 of this data set are located
at 38.04 and 78.5 respectively. Based on these values, the IQR is equal to 40.46 (78.5 - 38.04). Any value
that falls below -22.65 (38.04 - 1.5*40.46), or above 139.19 (78.5 + 1.5*40.46), can be considered an
outlier. In this case, there are no values that fall outside of the range and, consequently, no values should
be determined to be outliers.
Both of these methods are meant to determine any values that may be candidates for exclusion from the
data set. Data exclusion should be performed only if technical justification exists to support such action
(e.g., poor removals due to temporary maintenance or operational problems or known sampling problems).
For example, if an examination of the data set shows that an unusually high influent value is from the
same sampling day/event as an unusually high effluent value, this occurrence of corresponding extreme
values should be investigated to determine if the data values can be explained by technical or operational
problems not related to treatment system performance (e.g., maintenance, repair, or sampling problems). If
this is the case, dropping the data pair from the data set may be appropriate.
Review of the data may also show patterns such as increasing effluent values over time. If a similar pattern
is not observed for the influent values, this will generate a pattern of decreasing DREs over time. A graph
or plot of DRE against sampling day/event (in order from first to most recent sample) can help identify
such trends. This may alert the POTW to operational problems that should be investigated. A plot can also
highlight unusually low DREs that call for further review, such as checking laboratory quality control
samples to determine if blank or duplicate samples indicate anything out of the ordinary. If abnormalities
are found in laboratory QA/QC (quality assurance/quality control) data, the POTW may consider excluding
the affected values from the data set.
Whenever an influent sample is zero (or was reported as below the detection level and assigned a value of
zero)1, a DRE cannot be calculated regardless of the effluent value. Therefore, influent/effluent data pairs
for which the influent level is zero must be removed from the data set before calculating removal
efficiencies using the ADRE approach and the decile approach. However, the POTW can use these data in
calculating a removal efficiency using the MRE method since the MRE method does not involve the
calculation of individual DREs from each pair of influent and effluent values. If the data set contains
many pairs where the influent value is zero, the POTW should use caution in deciding whether or not using
these pairs is appropriate (mismatched data pairs are discussed further in the MRE section below).
A negative DRE is calculated when the effluent concentration (or loading) is higher than the influent
concentration (or loading). Negative daily removals should not automatically result in data elimination
since such values may be evidence of treatment system variability. Negative DREs (or for the MRE
method, the influent and effluent values that would calculate as negative DREs) should be retained in the
data set unless there is technical justification to remove them from the data set.
Handling of values reported as below detection level is discussed in Chapter 6.
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Example
Table 1 contains an example data set of 15 influent and effluent sample pairs for zinc. The influent and
effluent concentrations have been converted to loadings using the POTW flows for the sample days. The
influent and effluent concentrations may be used instead of converting to loadings. Whether loadings or
concentrations are used will likely have little impact on the results of the ADRE and decile approaches.
Influent and effluent flows are probably similar (if not the same) for a data pair and therefore will have
little effect on the relative size of the influent and effluent values, so DREs will change little. However,
converting to loadings may have a noticeable impact on the MRE method if a POTW has high variability in
its flows. Since influent and effluent loadings for high flow days will increase more relative to influent and
effluent loadings for low flow days, the net effect is to give greater weight to the removal rates on those
days with high flows. If the POTW has high variability in its flows, it should evaluate whether its removal
rates tend to go up and down in relation to flow. If so, the POTW should consider calculating an MRE
using both concentrations and loadings and evaluating which is more appropriate.
Table 1. Removal Efficiency Example
Sam nl e
Influent Load
KITIiiciil l.oad
mu:
l)av
Dale
(Ihs/dav)
(Ihs/dav)
r%)
1
3/4/99
518.22
111.41
78.50
2
3/5/99
163.98
173.99
-6.10
3
3/6/99
110.15
97.64
11.36
4
3/7/99
1739.93
474.41
72.73
5
3/8/99
266.48
320.45
-20.25
6
4/15/99
170.48
105.15
38.32
7
5/11/99
473.16
132.67
71.96
8
5/12/99
314.19
148.96
52.59
9
5/13/99
306.68
132.69
56.73
10
5/14/99
232.57
92.63
60.17
11
5/15/99
226.52
72.60
67.95
12
6/15/99
533.25
98.87
81.46
13
7/1/99
141.43
87.63
38.04
14
7/15/99
1166.77
103.90
91.10
15
8/1/99
2301.00
97.88
95.75
Average
577.65
150.06
52.69
Review of the data shows that:
• All the influent values are greater than zero (no data exclusion needed).
• The three particularly high influent values (sample days 4, 14, and 15) all have DREs of more than
70%, so the high influent values do not appear to make the data candidates for elimination.
• There are two effluent values (sample days 4 and 5) that are significantly higher than the others. For
116
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one, the corresponding influent value is also high and the DRE is 73%. For the other day, the DRE is
negative (-20%) since the influent value is relatively low. These results are from samples taken on two
consecutive days (March 7 and March 8), which may indicate that the POTW treatment system was
experiencing some operational difficulties or interference at the time. The POTW should investigate
the matter to determine if there are valid reasons for dropping these data from the removal calculations
data set.
• There are two negative DREs (one for March 8) calculated from the influent and effluent data pairs.
They occurred three days apart and may indicate temporary operational problems, so the POTW should
investigate the matter (as noted above).
A plot of the data may help the POTW identify any data concerns that should be investigated. Based on the
review of data for this example, it was determined that no justification exists for excluding any of the data
from the data set.
2.Calculation of Removal Efficiencies
Once the data set has been reviewed, the POTW can proceed to calculating removal efficiencies. The
following sections describe each of the methods for calculating removal efficiencies and perform the
calculations using the example data set in Table 1.
2.1 Average Daily Removal Efficiency (ADRE)
The ADRE is calculated by first calculating a DRE for each pair of influent and effluent values (i.e., an
influent value and an effluent value from the same sampling day/event are used to calculate a DRE). This
set of DREs is then averaged to determine the ADRE for a pollutant. Use of the ADRE method requires
that a POTW only use data for the sampling days/events for which it has both an influent and an effluent
value, and the influent value is greater than zero.
Example
For the example data set in Table 1, the ADRE is calculated as:
ADRE = [78.5+(-6.1)+ll.36+72.73+(-20.25)+38.32+71.96+52.59+56.73+60.17+67.95+81.46+38.04
+91.10+95.75)]/15 = 52.69%
2.2Mean Removal Efficiency (MRE)
The MRE is calculated by using the same formula as for the DRE (shown at the beginning of the
Appendix), but instead of using individual influent and effluent values from sampling days/events, the set
of influent values is first averaged to determine the average influent value and the same is done for the set
of effluent values (either concentrations or loadings). These average values are then used in the DRE
equation to result in the MRE for a pollutant. Unlike the ADRE method, the MRE method does not require
paired influent and effluent values from the same sampling days/events. The MRE can be based on
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influent and effluent sample values that are not always paired (e.g., one effluent sample is lost or destroyed,
so the influent average is based on one more value than the effluent average). However, the POTW should
use caution in building the data sets for calculating influent and effluent averages because if too many
unpaired values are used the removal efficiencies may be meaningless since the influent data and effluent
data may represent different time periods, and treatment plant conditions do vary over time.
Example
For the example data set in Table 1, the MRE is calculated as:
Average of the influent values = 577.65 lbs/day
Average of the effluent values = 150.06 lbs/day
MRE = 100*(577.65-150.06)/577.65 = 74.02%
2.3 Comparison of Results from ADRE and MRE Methods
Note that the MRE (74.02%) is higher than the ADRE (52.69%). The three days with the highest influent
loadings have relatively high DREs and the two negative DREs (Day 2 and Day 5) occur on days with
values that are not significantly greater than the other days. In the ADRE calculation, each day/DRE is
given the same weight as the others, while the MRE method gives greater weight to the days with greater
loadings. This means that the high removals on the days with high influent loadings affect the MRE more
than the other days do, leading to a higher MRE, while the negative values do not have as great an impact
since they occur on days with less elevated influent and effluent values If each DRE were to be weighted
by its proportion of the total loading, the result would be the same as with the MRE method.
Usually, the MRE and ADRE are slightly different from each other, and can be quite different (as in the
example presented here). The POTW can calculate both and decide if one of the estimates is the most
appropriate for use in AHL calculations. The POTW can also use the decile approach to determine
representative removal efficiencies.
2.4 Decile Approach
The decile approach, unlike the above methods, considers how often the actual DRE will be above or
below a specified removal rate, thereby taking into account the variability of POTW removal efficiencies
over time. The decile approach involves putting the set of DREs (calculated using the formula presented at
the beginning of this appendix) in order from least to greatest and then determining nine decile values.
Each decile is the value below which a certain percentage of the DREs fall. For example, the first decile is
the value below which 10% of the DREs fall. Similarly, the second decile is the value below which 20% of
the DREs fall, on up to the ninth decile, which is the value below which 90% of the DREs fall. The fifth
decile is the median and half of the DREs fall below this number. To apply the decile approach, a
minimum of nine DREs are required. If exactly nine DREs are available, the nine estimated deciles are
simply the nine DREs. If more then nine DREs are used, the POTW needs to calculate the nine decile
estimates.
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Tables 2 and 3 below illustrate use of the decile approach for the example zinc data set. The steps are:
• Step 1: Take the set of DREs and put the values in order from smallest to largest (see Table 2).
• Step 2: The entries for Column 1 are obtained by performing the two calculations. First, define the
location for the first decile and then calculate the next eight multiples of that location value to
determine the location for the second through ninth deciles. The first location is determined by the
equation: (N+l)/10, where N = the number of data pairs/DREs used. For the example data set, N=15,
so the location for the first decile is (15+1)/10 = 1.6. The location for the second decile is 2 x 1.6 = 3.2,
the location for the third decile is 3 x 1.6 = 4.8, and so on up to the ninth decile of 9 x 1.6 = 14.4.
(Column 1 in Table 3)
• Step 3: For each decile, take the whole number part of the value in Column 1 and place it in Column 2
(e.g., the first decile is 1.6, so the whole number part is 1; the fourth decile is 6.4, so the whole number
part is 6).
• Step 4: The entries in Column 3 of Table 3 are taken from the ordered list of DREs in Table 2. The
whole number values in Column 2 correspond to the entry in the ordered list in Table 2 [e.g., the whole
number part for the first decile is 1, so entry 1 (-20.25%) from Table 2 is the correct value and is placed
in Column 3 of Table 3; similarly, the fourth decile whole number part is 6, so value 6 (52.59%) is
placed in Column 3 of Table 3 for the fourth decile],
• Step 5: Following a similar procedure as in Step 4, values for Column 4 are taken from Table 2 and
place in Table 3, except that this time the values taken from Table 2 are the ones that immediately
follow the Column 3 entries [e.g., for the first decile, the value placed in Column 4 is -6.10, which is
value 2 (the value immediately after value 1) from Table 2; for the fourth decile, the value placed in
Column 4 is 56.73, which is value 7 from Table 2],
• Step 6: Fill in Column 5 by subtracting Column 3 from Column 4 and entering the result.
• Step 7: Similar to the process for filling Column 2 (explained in Step 3) of Table 3, place the decimal
part of the Column 1 entries in Column 6 of Table 3 (e.g., for the first decile, use 0.6; for the fourth
decile, use 0.4).
• Step 8: Fill in Column 7 by multiplying the values in Column 5 by the values in Column 6 and entering
the result.
• Step 9: Add Column 3 and Column 7 and enter the result in Column 8 of Table 3. These values are the
estimated deciles.
Table 2. Set of DREs Sorted in Ascending Order
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
-20.25
-6.1
11.36
38.04
38.32
52.59
56.73
60.17
67.95
71.96
72.73
78.50
81.46
91.10
95.75
119
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Table 3. Decile Approach for Zinc Example
Deciles
Column 1
Column 2
Column 3
Column 4
Column 5
Column 6
Column 7
Column S
1st
1.6
1
-20.25
-6.10
14.15
0.6
8.490
-11.76
2nd
3.2
3
11.36
38.04
26.68
0.2
5.336
16.70
3rd
4.8
4
38.04
38.32
0.28
0.8
0.224
38.26
4th
6.4
6
52.59
56.73
4.14
0.4
1.656
54.25
5th
8.0
8
60.17
67.95
7.78
0
0.000
60.17
6th
9.6
9
67.95
71.96
4.01
0.6
2.406
70.36
rjth
11.2
11
72.73
78.50
5.77
0.2
1.154
73.88
8th
12.8
12
78.50
81.46
2.96
0.8
2.368
80.87
9th
14.4
14
91.10
95.75
4.65
0.4
1.860
92.96
The main value of the decile approach is that it provides an estimate of how often a POTW is expected to
exceed certain removal values, such as the ADRE and MRE. For the example, the ADRE is 53% and the
MRE is calculated as 74%. If the POTW uses either one of these values, what amount of the time will its
removal efficiency exceed those values? This can be estimated using the decile approach. The ADRE of
53%) falls between the third and fourth deciles (38.26%> and 54.25%, respectively), meaning that the actual
removal efficiency is estimated to exceed the ADRE 60% to 70% of the time [(e.g., the third decile means
that 30%) of the time values will fall below that value (38.26% in this case)]. The MRE of 74% lies
between the seventh and eight deciles (73.88% and 80.87%, respectively), so the POTW is estimated to
exceed the MRE 20% to 30% of the time.
In developing local limits, appropriate removal efficiencies must be selected for calculation of AHLs for
each pollutant. POTWs have often selected a pollutant's ADRE for local limits calculations. EPA
recommends that POTWs consider using the decile approach or the MRE method since they better account
for variabilities in removal efficiencies over time. For example, since a higher removal efficiency means
more pollutant is removed to the sludge, if the POTW used the ADRE from the above example (which is
likely exceeded 60% to 70% of the time) to calculate an AHL to protect sludge quality, the resulting AHL
may not be adequately protective. More pollutant will likely be removed to the sludge 60% to 70% of the
time, so loadings in the sludge will higher than was estimated in the AHL calculations and may lead to
exceedances of sludge disposal standards.
A different approach that may address this concern is to use one decile for AHL calculations to protect
sludge quality (for sludge disposal and for sludge digester inhibition for conservative pollutants) and a
different decile for AHL calculations for protection against Pass Through concerns (e.g., NPDES permit
limits). For example, a POTW can base its sludge quality-based AHLs on the seventh decile removal
which means that greater removals to sludge and hence greater sludge loadings would be estimated to
occur 30%) of the time. Similarly, the POTW can use the third decile for calculating its water quality-based
AHLs since lower removals (and hence higher effluent loadings) would be estimated to occur about 30% of
the time. Although use of these deciles estimates that AHLs would be exceeded 30% of the time, in reality
120
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this is not highly likely. If the entire AHL is allocated to IUs all IUs would have to discharge at their
maximum allowed level to reach the AHL. Then if the removal achieved is greater than the seventh decile,
more loading would go to the sludge than is provided for with the AHL. If some IUs discharge at below
their allocated loadings, which is very likely at any given time, the likelihood of exceeding the allowed
loading to the sludge is much lower.
3.Non-Conservative pollutants
The above discussion of removal efficiency calculations applies to conservative pollutants (e.g., metals).
However removal efficiencies for non-conservative pollutants can be used to calculate AHLs based on Pass
Through criteria (e.g., biological process inhibition data, NPDES permit limits) and the guidance above can
be used for non-conservative pollutants only in these cases. Conservative pollutant removal efficiencies
are determined by pollutant concentrations in the POTW influent and effluent streams. The presumption
applied to conservative pollutants (that removed pollutants are exclusively transferred to the POTW's
sludge streams) cannot be extended to non-conservative pollutants since losses through degradation and
volatilization do not contribute to pollutant loadings in sludge. Therefore, non-conservative pollutant
removal efficiencies cannot be used in deriving AHLs from criteria/standards applicable to the POTW's
sludge streams (e.g., digester inhibition, sludge disposal).
The equation for calculating AHLs for non-conservative pollutants, based on criteria for sludge disposal or
sludge digester inhibition, is:
Where:
Linfl = Allowable influent loading, lbs/day
Lcinf = POTW influent loading, lbs/d
Ccrit = Sludge criteria, mg/kg dry sludge
Csldg = Existing sludge pollutant level (in sludge to disposal or to digester), mg/kg dry sludge.
The equation can be rewritten as:
Where the factor Cdig/Lcinf is a partitioning factor that relates the pollutant level in the POTW sludge
(Cdig) to the headworks loading of the pollutant (Lcinf). The partitioning factor enables calculation of an
AHL (Linfl) from a sludge criterion/standard (Ccrit) for a non-conservative pollutant. To determine the
partitioning factor for a particular pollutant, the POTW's influent and sludge must be routinely sampled for
Linfl (L cinf ) *
CRIT
T v—- e.ru i
_LjATJ7T
121
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that pollutant.
The factor Cdig/Lcinf expresses non-conservative pollutant removals to sludge. Non-conservative
pollutant removals to sludge are highly variable, and are dependent on such factors as wastewater
temperature, ambient air temperature, biodegradation rates (which are temperature dependent), aeration
rates, and POTW influent flow. Since non-conservative pollutant removals to sludge are highly variable,
the variability in non-conservative pollutant sludge partitioning factors should be addressed in the local
limits development process. The procedures and recommendations presented in this manual for addressing
removal efficiency variability for conservative pollutants (e.g., the calculation of mean removals and the
decile approach) can be extended to addressing variability in non-conservative pollutant sludge partitioning
factors. In calculating sludge AHLs, the sludge partitioning factor should be used in place of the removal
efficiency for non-conservative pollutants.
122
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Appendix M - Specific Gravity of Sludge
The allowable headworks loading (AHL) equations presented in Chapter 6 for sewage sludge disposal
contain a factor for the specific gravity of sludge (sludge density). This factor accounts for differences in
the density of sludge based on the percent solids of sludge to disposal. The unit conversion factor (8.34) in
the same equations converts the overall units into pounds per day (lbs/day), using a specific gravity or
density of sludge equal to 1 kg/1, which assumes that sludge has the same density as water. If the
dewatered sludge density is different from the density of water, the unit conversion factor is not fully
accurate. As the percent solids of a sludge increases, the density of the sludge increases and therefore the
error introduced by the inaccurate unit conversion factor increases. To correct this inaccuracy, the
numerator of the AHL equation should be multiplied by the specific gravity of the dewatered sludge (as
noted in Chapter 6). If a sludge is not dewatered before disposal, the inaccuracy produced by using the unit
conversion factor (8.34) without a specific gravity factor would probably not be significant.
The POTW can determine the specific gravity (density) of its sludge prior to disposal through a simple
laboratory measurement. The POTW should take this measurement as part of its local limits monitoring
program and average the resulting data set (e.g., 7-10 data points) to determine a representative sludge
specific gravity (density) factor for use in local limits calculations. The POTW can also estimate the
specific gravity of its sludge using the equations below and information on the percent solids.
For a typical wet sludge at 10% solids, the approximate density is 1.03 kg/1. For a typical dewatered
sludge at 30% solids, the approximate density is 1.11 kg/1. A sludge at 50% solids may reach a density of
1.2 to 1.3 kg/1, which would result in a 20% to 30% conservative error in the calculation of an AHL if a
specific gravity factor is not used. All of these values depend on the amount of volatile solids in the sludge
in comparison with the amount of fixed mineral solids, which vary with percent solids, and the densities of
each of these types of solids.
Mws _ Ms Mw
Sws Ss Sw
Where:Mws = Mass of wet sludge (kg)
Sws = Specific gravity of wet sludge (kg/1)
Ms = Mass of dry sludge solids (kg)
Ss = Specific gravity of sludge solids (kg/1)
Mw = Mass of water (kg)
Sw = Specific gravity of water (kg/1).
Ms _ Mf j^Mv
Ss Sf Sv
Where:MF = Mass of fixed solids (kg)
Sf = Specific gravity of fixed solids (kg/1)
My = Mass of volatile solids (kg)
Sv = Specific gravity of volatile solids (kg/1).
The result from the second equation is used in the first equation.
123
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Example
Sludge is 10% solids:
Assume solids consist of 33% fixed mineral solids with a specific gravity of 2.5 kg/1 and 67% volatile
solids with a specific gravity of 1.2 kg/1.
^ = !«). 10)xMm ] + j
Sws 1-45 1
To determine the specific gravity of the dry sludge solids, use the second equation:
which results in Ss = 1.45 kg/1. Using this value in the first equation:
— = [(0.33jx—l [(0.67)x—J
Ss 2.5 1.2
which yields Sws = 1.03 kg/1.
124
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Appendix N - Sludge AHL Equations Using Flow (in metric units)
Some POTWs may have sludge flow data available in dry metric tons per day, rather than MGD. The AHL
equations for sludge disposal in Chapter 6 can be converted to use sludge flow data in these units. Some of
the equations in Chapter 6 are presented below using flows in dry metric tons per day. Use of these "dry
flows" eliminates the need for the specific gravity factor in the equations.
General Sludge Equation for Conservative Pollutants
T _ ^ S&rx?) (D. 0022)
1NFJ- r>
^POTW
Where:
Linfl = Allowable influent loading, lbs/day
Ccrit = Sludge criteria, mg/kg dry sludge
Qsldg = Total sludge flow to disposal, dry metric tons per day
Rpotw = Removal efficiency across POTW (as decimal)
0.0022 = Unit conversion factor.
Land Application
As explained in Chapter 6, determining the land application sludge criteria for use in the general sludge
equation requires that the POTW first convert 40 CFR §503 Table 2 and Table 4 sludge criteria into values
in mg/kg of dry sludge units. Since Table 2 and Table 4 criteria are in Metric units (kg/ha), they must be
converted into English units (lbs/acre) so that they can be used with the equations in Chapter 6 which use
other English units (e.g., flow in MGD, area in acres). Table 2 and Table 4 criteria are provided in both
Metric and English units in Appendix CC.
Another option is for POTWs to use the land application criteria equations in Metric units (e.g., area in
hectares, flow in dry metric tons per day), thus eliminating the need to convert Table 2 and Table 4 values
to English units. These equations are provided below. These equations avoid the need for a specific
gravity factor since they use also use a "dry flow" for sludge.
c _ (CajM)(SA)
{SLKQu) (0.36S)
125
-------
Where:
Ccrit = Sludge criteria, mg/kg dry sludgeCcuM = Federal (Table 2 of 40 CFR 503.13) or State land
application cumulative pollutant loading rate, kg/ha
SA = Site area, hectares
SL = Site life, years
Qla = Sludge flow to bulk land application at an agricultural, forest, public contact, or reclamation
site, dry metric tons per day
0.365 = Unit conversion factor.
£ _
CKrr (AWSAR)(P 001)
Where:
Ccrit = Sludge criteria, mg/kg dry sludge
Cann = Federal (Table 4 of 40 CFR 503.13) or State land application annual pollutant loading rate,
kg/ha
AWSAR = Annual whole sludge application rate, metric tons per hectare per year dry weight basis
0.001 = Unit conversion factor.
126
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Appendix O - Closed-cup Flashpoints for Select Organic
Compounds
Pollutant
Closed Cup
Flashpoint (°F)
Acrolein
-15
Acrylonitrile
30
Benzene
12
Chlorobenzene
82
Chloroethane (Ethyl chloride)
-58
1,1 -Dichloroethane
2
1,2-Dichloroethane (Ethylene dichloride)
56
1,1-Dichloroethylene (Vinylidene chloride)
-2
Trans-1,2-Dichloroethylene, (1,2-Dichloroethylene)
36-39
1,2-Dichloropropane (Propylene dichloride)
60
Ethylbenzene
55
Toluene
40
Source: NIOSHPocket Guide to Chemical Hazards, National Institute for
Occupational Safety and Health, DHHS (NIOSH) Pub. No. 99-115, April
1999.
127
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Appendix P - Discharge Screening Levels and Henry's Law
Constants for Select Organic Compounds
DISCHARGE SCREENING LEVELS BASED ON EXPLOSIVITY
Pollutant
LELs(l)
% volume / volume
LELs
(mol/m3)
Henry's Law
Constant
(mol/m3)/(mg/L)
MW
(g/mol)
Discharge Screening Level
(mg/L)
Acrolein
2.8
1.15
8.7E-05
56.1
13163
Acrvlonitrile
3.0
1.23
8.4E-05
53.1
14586
Benzene
1.2
0.49
2.9E-03
78.1
169
Chlorobenzene
1.3
0.53
1.3E-03
112.6
395
Chloroethane
3.8
1.55
7.0E-03
65.5
222
1.1 -Dichloroethane
5.4
2.21
2.4E-03
99
909
1,2-Dichloroethane
6.2
2.54
4.9E-04
99
5221
1,1 -Dichloroethvlene
6.5
2.66
1.2E-02
97
215
Trans-1,2-Dichloroethvlene
5.6
2.29
4.0E-03
97
571
1,2-Dichloropropane
3.4
1.39
1.0E-03
113
1326
Ethvl benzene
0.8
0.33
3.1E-03
106.2
106
Methvl bromide
10.0
4.09
2.7E-03
95
1521
Methvl chloride
8.1
3.31
7.4E-03
50.5
450
Methylene Chloride
13.0
5.32
1.2E-03
84.9
4307
Toluene
1.1
0.45
3.0E-03
92.1
152
1,1,2-Trichloroethane
6.0
2.45
2.6E-04
133.4
9611
1,1,1-Trichloroethane
7.5
3.07
5.2E-03
133.4
591
Trichloroethvlene
8.0 (F)
3.20
3.1E-03
131.4
1029
Vinyl Chloride
3.6
1.47
1.7E-02
62.5
88
LELs assumed 25°C unless noted otherwise.
Source:
1 Pocket Guide to Chemical Hazards, National Institute for Occupational Safety and Health(NIOSH),
DHHS, Pub. No. 99-115, April 1999.
128
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DISCHARGE SCREENING LEVELS BASED UPON FUME TOXICITY
Pollutant
Exposure
Limit
(my/in3)
Guideline
Reference
Henry's Law
Constant
(mg/m3) /
(mg/L)
Discharge
Screening
Level
(mg/L)
Acrolein
0.69
STEL
v (ACGIH)
4.9
0.141
Acrylonitrile
21.7
Ceiling
t (OSHA)
4.5
4.822
Benzene
79.8
Ceiling
t (OSHA)
228.0
0.350
Bromoform
5
PEL-TWA
t (OSHA)
22.8
0.219
Carbon tetrachloride
157.3
Ceiling
t (OSHA)
1185.0
0.133
Chlorobenzene
350
PEL-TWA
t (OSHA)
151.0
2.318
Chloroethane
2600
PEL-TWA
t (OSHA)
449.0
5.791
Chloroform
240
Ceiling
t (OSHA)
163.5
1.468
1,1 -Dichloroethane
400
PEL-TWA
t (OSHA)
240.4
1.664
1,2-Dichloroethane
405
Ceiling
t (OSHA)
48.1
8.423
1,1 -Dichloroethylene
79
STEL
v (ACGIH)
1202.1
0.066
Trans-1,2-
Di chl oroethy 1 ene
790
PEL-TWA
t (OSHA)
389.3
2.030
1,2-Dichloropropane
508
STEL
v (ACGIH)
118.5
4.288
Ethyl benzene
543
STEL
v (ACGIH)
327.0
1.661
Methyl bromide
80
Ceiling
t (OSHA)
255.5
0.313
Methyl chloride
414
Ceiling
t (OSHA)
371.6
1.114
Methylene chloride
434
Ceiling
t (OSHA)
104.8
4.141
1,1,2,2,-T etrachl or ethane
35
PEL-TWA
t (OSHA)
18.6
1.884
T etrachl oroethy 1 ene
685
STEL
v (ACGIH)
717.1
0.955
Toluene
1131
Ceiling
t (OSHA)
272.5
4.151
1,1,2-Tri chloroethane
45
PEL-TWA
t (OSHA)
34.1
1.321
1,1,1 -Tri chloroethane
2460
STEL
v (ACGIH)
692.7
3.551
Tri chl oroethy 1 ene
1074
Ceiling
t (OSHA)
408.7
2.628
Vinyl Chloride
12.8
Ceiling
t (OSHA)
1048.0
0.012
v = Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure
Indices(TLVs and BEIs), ACGIH 1997.
t = 29 CFR 1900.1000, Title 29, Volume 6, Parts 1910.1000 to end, Revised July 1, 1998 Occupational
Safety and Health Administration(OSHA).
129
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HENRY'S LAW CONSTANTS EXPRESSED IN ALTERNATE UNITS
Pollutant
Henry's Law
Constant(2)
M/atm
@298K(25°C)
Henry's Law
Constant
(atm m3 / mol)
Henry's Law
Constant
(mol/m3 /
mg/L)
Henry's Law
Constant
(mg/m3 /
mg/L)
Acrolein
8.2
0.00012
0.000087
4.9
Acrylonitrile
9.15
0.00011
0.000084
4.5
Benzene
0.18
0.0056
0.0029
228
Bromoform
1.8
0.00056
23
Carbon Tetrachloride
0.034
0.029
1185
Chlorobenzene
0.27
0.0037
0.0013
151
Chloroethane
0.089
0.011
0.007
449
Chloroform
0.25
0.004
164
1,1 -Dichloroethane
0.17
0.0059
0.0024
240
1,2-Dichloroethane
0.85
0.0012
0.00049
48
1,1 -Dichloroethylene
0.034
0.029
0.012
1202
Trans-1,2-Dichloroethylene
0.105
0.0095
0.004
389
1,2-Dichloropropane
0.345
0.0029
0.001
119
Ethyl benzene
0.125
0.008
0.0031
327
Methyl bromide
0.16
0.0063
0.0027
256
Methyl chloride
0.11
0.0091
0.0074
372
Methylene Chloride
0.39
0.0026
0.0012
105
1,1,2,2,-T etrachl or ethane
2.2
0.00045
19
T etrachl oroethy 1 ene
0.057
0.018
717
Toluene
0.15
0.0067
0.003
273
1,1,2-Tri chloroethane
1.2
0.00083
0.00026
34
1,1,1 -Tri chloroethane
0.059
0.017
0.0052
693
Tri chl oroethy 1 ene
0.1
0.01
0.0031
409
Vinyl Chloride
0.039
0.026
0.017
1048
Source: Compilation of Henry's Law Constants for Inorganic and Organic Species of Potential Importance in Environmental
Chemistry, R. Sanders 1999(version 3); lillp /Avww mpch-mainz mpg rle/~sanrler/res/lienry html
130
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Appendix Q - OSHA. ACGIH and NIOSH Exposure Levels
EXPOSURE LIMITS FROM VARIOUS AGENCIES FOR VOLATILE ORGANIC PRIORITY POLLUTANTS
OSHA Exposure Limits
ACGIH
NIOSH
Volatile Organic
Compounds
PEL/TWA
ppm (mg/m3)
Ref.
Ceiling
Limit
nnm
Ref.
STEL
ppm
STEL
mg/m3
Ceiling Limit
ppm (mg/m
Ref.
TWA
ppm
STEL
ppm
(1112/1113)
C
ppm
Ref.
Acrolein
0.1 (0.251
t
0.3
0.69
0.1 (0.231d
V
0.1 (0.251
0.3 (0.81
n
Acrvlonitrile
2
n(a1
10
n(a1
1
10
n(a)
Benzene
10
t
25
t
2.5
8
V
0.1
1
n
Bromoform
0.5 (5.01
t(a1
0.5 (51
n(a)
Carbon
Tetrachloride
10
t
25
t
10
63
v(a)
2(12.6)
n
Chlorobenzene
75 (3501
t
Chloroethane
(Ethvl chloride)
1000(2600)
t
Chloroform
(CI 50 (2401
t
2 (9.781
n
Dichloroethane,
1.1-
100(400)
t
100(400)
n
Dichloroethane, 1,2-
(Ethylene
dichloride)
50
t
100
t
1(4)
2(8)
n
Dichloroethylene,
1,1- (Vinylidene
chloride)
none
n
none
n
20
79
V(P)
trans-
Dichloroethylene, 1,
2-
(U-
Dichloroethvlenel
200(790)
t
200(790)
n
Dichloropropane, 1,
2- (Propylene
dichloride)
75(350)
t
110
508
V
Ethvl benzene
100(4351
t
125
543
V
100(4351
125(5451
n
Methvl bromide
(CI 20 (801
t(a1
Methvl chloride
100
t
200
t
100
207
v(a1
Methylene Chloride
(Dichloromethanel
25
n
125
n
T etrachlorethane,
1.1.2.2-
5.0(35)
t(a)
1(7)
n(a)
a- designated as skin in reference
p- indicates proposed notice of intended change
* NIOSH recommends 60 minute (C) of 2ppm and 25ppm lOhour TWA (Appendix C)
C -indicates ceiling not to be exceeded
References
v- Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices(TLVs and BEIs), ACGIH 1997.
t- Occupational Safety and Health Administration(OSHA), 29 CFR 1900.1000, Title 29, Volume 6, Parts 1910.1000 to end, Revised as of July 1, 1998.
n- NIOSH Pocket Guide to Chemical Hazards, National Institute for Occupational Safety and Health, DHHS (NIOSH) Pub. No. 99-115, April 1999
d- ACGIH Documentation of the Threshold Limit Values and Biological Exposure Indices, Sixth Edition vol. 1&2, 1990, 1996 supplements
131
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