MEMORANDUM 

TO: Brian D’Amico, USEPA/EAD 

FROM: Cuc Schroeder, USEPA/EAD 

DATE: November, 2010 

SUBJECT: Statistical Support Memorandum 

Airport Statistical Survey Design 

EPA developed a sample frame design for the airport survey based on airport size and climate. 

Although deicing operations are prevalent at colder climate airports, EPA needed to determine the 

extent that airports in warmer climates also have anti-icing operations. For example, flights that 

originate at these airports may land in airports with wintry weather conditions. Additionally, dryweather deicing may also be performed on some types of aircraft whose fuel tanks become supercooled during high-altitude flight, resulting in ice formation at lower altitudes and after landing. Thus 

all airports classified by FAA as large and medium hubs, regardless of climate, were sampled with 

certainty. These large and medium hubs account for 80 percent of commercial departures and 

enplanements. Five general aviation airports with at least five cargo departures on average per day 

were also surveyed as a judgment sample to better understand deicing/anti-icing operations at small 

airports with significant cargo-only service. 

EPA also selected all small and nonhub airports (excluding Alaskan airports) with at least 30,000 

annual jet departures. The remaining airports were stratified by the number of significant snow or 

freezing precipitation days (SOFP) as determined by the NOAA data. EPA selected 14.5 SOFP days 

for stratification, and oversampled those airports with more than 14.5 SOFP days per year. 

For Alaska airports, one medium hub airport in Alaska was sampled with certainty. EPA then 

selected a judgment sample of small and nonhub Alaskan airports to better understand their 

deicing/anti-icing operations and economic profile as a judgment sample. EPA chose airports based 

on activity that would capture the major climate zones in Alaska (e.g., coastal). 

Statistical Analysis for COD and Ammonia Limitations and Standards 

Appendices to this memorandum provide information summarizing the statistical analyses conducted 

on the long-term data provided by Albany Airport representing the treatment performance of 

Anaerobic Fluidized Bed (AFB) treatment for airport deicing stormwater. Included with this 

memorandum are seven appendices related to the COD and ammonia long-term data analyses. 

In the calculations used to set the COD limits, any effluent concentration from unit R_101 (variable 

name ArprtR_101) or unit R_102 (variable name ArprtR_102) with an original recorded value of 0 

mg/L was changed to 2 mg/L. EPA deemed that this change was necessary since the industry data 

had a lower measurement limit of 2.0 mg/L.
Memorandum 

November, 2010 

Page 2 

2 

Appendix COD, Attachment 1 – Presents plots of the original COD data submitted by Albany airport 

before any exclusions were applied. 

Appendix COD, Attachment 2 – Presents the estimated data in the original data set submitted from 

Albany airport that were excluded from the basis for limitations. 

Appendix COD, Attachment 3 – Presents a listing of the daily COD values used as the basis for the 

COD limitations. 

Appendix COD, Attachment 4 – Presents plots of the daily COD values used as the basis for the 

COD limitations, by deicing season. 

Appendix COD, Attachment 5 – Presents a list of the weekly COD averages calculated using the 

daily COD values. 

Appendix COD, Attachment 6 – Identifies the weekly COD averages from the Albany data set that 

are greater than the weekly average limitations for COD. 

Appendix Ammonia – Provides an overview of the lognormal distribution analysis conducted on the 

Albany ammonia long-term data for development of the ammonia limitations and standards. 

 

 
APPENDIX COD, Attachment 1 

1 

APPENDIX COD, Attachment 1 

Plots of the Original Data Submitted by Albany (Before Exclusions) 

The following plots show all available COD concentrations for Albany from 1999 to 2009. There is 

one plot for each deicing season going from the fall to the following summer. The plots show the 

date, the influent concentration, the effluent concentration from unit R_101 (variable name 

ArprtR_101), and the effluent concentration from unit R_102 (variable name ArprtR_102). 

Concentrations are in mg/l and are shown using a log scale. Concentrations of “0” are replaced with 

“0.5” for the purpose of constructing a plot using the log scale. 
APPENDIX COD, Attachment 1 

2 

Season99-All Data

0.1

1

10

100

1000

10000

100000

11/15/1999 12/15/1999 1/15/2000 2/15/2000 3/15/2000 4/15/2000 5/15/2000 6/15/2000 7/15/2000

COD(mg/l)

OriginalR101

OriginalR102

OriginalInf

Season00-All Data

0.1

1

10

100

1000

10000

100000

11/15/00 12/15/00 1/15/01 2/15/01 3/15/01 4/15/01 5/15/01 6/15/01 7/15/01

COD(mg/l)

OriginalR101

OriginalR102

OriginalInf
APPENDIX COD, Attachment 1 

3 

Season01-All Data

0.1

1

10

100

1000

10000

100000

11/15/2001 12/15/2001 1/15/2002 2/15/2002 3/15/2002 4/15/2002 5/15/2002 6/15/2002 7/15/2002

COD (mg/l)

OriginalR101

OriginalR102

OriginalInf

Season02-All Data

0.1

1

10

100

1000

10000

100000

11/15/02 12/15/02 1/15/03 2/15/03 3/15/03 4/15/03 5/15/03 6/15/03 7/15/03

COD (mg/l)

OriginalR101

OriginalR102

OriginalInf
APPENDIX COD, Attachment 1 

4 

Season03-All Data

0.1

1

10

100

1000

10000

100000

11/15/03 12/15/03 1/15/04 2/15/04 3/15/04 4/15/04 5/15/04 6/15/04 7/15/04

COD (mg/l)

OriginalR101

OriginalR102

OriginalInf

Season04-All Data

0.1

1

10

100

1000

10000

100000

11/15/04 12/15/04 1/15/05 2/15/05 3/15/05 4/15/05 5/15/05 6/15/05 7/15/05

COD (mg/l)

OriginalR101

OriginalR102

OriginalInf
APPENDIX COD, Attachment 1 

5 

Season05-All Data

0.1

1

10

100

1000

10000

100000

11/15/05 12/15/05 1/15/06 2/15/06 3/15/06 4/15/06 5/15/06 6/15/06 7/15/06

COD (mg/l)

OriginalR101

OriginalR102

OriginalInf

Season06-All Data

0.1

1

10

100

1000

10000

100000

11/15/06 12/15/06 1/15/07 2/15/07 3/15/07 4/15/07 5/15/07 6/15/07 7/15/07

COD (mg/l)

OriginalR101

OriginalR102

OriginalInf
APPENDIX COD, Attachment 1 

6 

Season07

0.1

1

10

100

1000

10000

100000

11/15/07 12/15/07 1/15/08 2/15/08 3/15/08 4/15/08 5/15/08 6/15/08 7/15/08

COD (mg/l)

OriginalR101

OriginalR102

OriginalInf

Season08-All Data

0.1

1

10

100

1000

10000

100000

11/15/08 12/15/08 1/15/09 2/15/09 3/15/09 4/15/09 5/15/09 6/15/09 7/15/09

COD (mg/l)

OriginalR101

OriginalR102

OriginalInf
 APPENDIX COD, Attachment 2 

1 

APPEDIX COD, Attachment 2

Estimated Data in Original Submittal from Albany Airport (And Excluded As Basis for 

Limitations) 

Table 1 Unit ArprtR-101 Estimated Data 

Estimated Values Indicated by: Number of Days Excluded Start Date End Date 

Italicized Text 1 12/18/1999 12/18/1999 

 1 12/31/1999 12/31/1999 

 5 1/4/2000 1/8/2000 

 7 1/10/2000 1/16/2000 

 1 2/10/2000 2/10/2000 

 1 2/14/2000 2/14/2000 

 1 2/19/2000 2/19/2000 

 2 3/24/2000 3/25/2000 

 1 12/2/2000 12/2/2000 

 1 1/29/2001 1/29/2001 

 1 2/9/2001 2/9/2001 

 1 2/18/2001 2/18/2001 

 1 3/6/2001 3/6/2001 

 1 3/20/2001 3/20/2001 

 1 5/6/2001 5/6/2001 

 3 6/16/2001 6/18/2001 

 2 6/23/2001 6/24/2001 

 2 12/14/2001 12/15/2001 

 1 1/7/2002 1/7/2002 

 1 1/20/2002 1/20/2002 

 1 1/29/2002 1/29/2002 

 1 5/25/2002 5/25/2002 

 1 6/1/2002 6/1/2002 

 1 12/26/2002 12/26/2002 

 1 1/5/2003 1/5/2003 

 1 1/27/2003 1/27/2003 

 3 2/1/2003 2/3/2003 

 1 2/8/2003 2/8/2003 

 1 4/16/2003 4/16/2003 

 2 5/17/2003 5/18/2003 

 1 12/5/2003 12/5/2003 

 1 12/13/2003 12/13/2003 

 1 1/28/2004 1/28/2004 

 1 2/7/2004 2/7/2004 

 1 2/14/2004 2/14/2004 

 1 2/21/2004 2/21/2004 

 1 2/28/2004 2/28/2004 

 1 3/6/2004 3/6/2004 

 6 12/17/2004 12/22/2004 

 2 3/5/2005 3/6/2005 

 1 3/8/2005 3/8/2005 
 APPENDIX COD, Attachment 2 

2 

Estimated Values Indicated by: Number of Days Excluded Start Date End Date 

 2 3/15/2005 3/16/2005 

 1 4/12/2005 4/12/2005 

 1 5/13/2005 5/13/2005 

 1 12/2/2005 12/2/2005 

 1 1/23/2006 1/23/2006 

 1 2/11/2006 2/11/2006 

 1 3/7/2006 3/7/2006 

 2 3/22/2006 3/23/2006 

 1 1/12/2007 1/12/2007 

 2 3/16/2007 3/17/2007 

 4 4/10/2007 4/13/2007 

 2 6/4/2008 6/5/2008 

 13 11/26/2008 12/8/2008 

Three or more sequential values 5 12/2/1999 12/11/1999 

 3 12/24/1999 12/26/1999 

 12 1/5/2000 1/16/2000 

 2 3/24/2000 3/25/2000 

 2 5/31/2001 6/1/2001 

 4 6/8/2001 6/11/2001 

 3 6/16/2001 6/18/2001 

 2 6/23/2001 6/24/2001 

 2 6/1/2002 6/2/2002 

 3 6/9/2002 6/11/2002 

 2 1/4/2003 1/5/2003 

 4 3/5/2005 3/8/2005 

 2 3/15/2005 3/16/2005 

 2 3/24/2005 3/25/2005 

 2 12/12/2005 12/13/2005 

 2 12/18/2005 12/19/2005 

 2 3/3/2006 3/4/2006 

 2 3/22/2006 3/23/2006 

 3 4/14/2006 4/16/2006 

 6 2/14/2007 2/19/2007 

 2 3/11/2007 3/12/2007 

 2 5/19/2007 5/20/2007 

 2 1/2/2008 1/3/2008 

 2 5/13/2008 5/14/2008 

 14 11/25/2008 12/8/2008 

Three or more sequential values of 3 4/7/2000 4/9/2000 

zero concentrations 8 12/15/2004 12/22/2004 

 
 APPENDIX COD, Attachment 2 

3 

Table 2 Unit ArprtrR-102 Estimated Data 

Estimated Values Indicated by: Number of Days Excluded Start Date End Date 

Italicized Text 1 12/18/1999 12/18/1999 

 1 12/31/1999 12/31/1999 

 1 2/14/2000 2/14/2000 

 1 2/19/2000 2/19/2000 

 2 3/10/2000 3/11/2000 

 2 3/24/2000 3/25/2000 

 1 4/9/2000 4/9/2000 

 1 12/2/2000 12/2/2000 

 1 1/29/2001 1/29/2001 

 1 2/9/2001 2/9/2001 

 1 2/18/2001 2/18/2001 

 1 3/20/2001 3/20/2001 

 3 6/16/2001 6/18/2001 

 2 6/23/2001 6/24/2001 

 2 12/14/2001 12/15/2001 

 1 1/7/2002 1/7/2002 

 1 1/20/2002 1/20/2002 

 1 1/29/2002 1/29/2002 

 1 6/1/2002 6/1/2002 

 1 12/26/2002 12/26/2002 

 1 1/27/2003 1/27/2003 

 3 2/1/2003 2/3/2003 

 1 2/8/2003 2/8/2003 

 1 12/13/2003 12/13/2003 

 1 1/28/2004 1/28/2004 

 1 2/7/2004 2/7/2004 

 1 2/14/2004 2/14/2004 

 1 2/21/2004 2/21/2004 

 1 2/28/2004 2/28/2004 

 1 3/6/2004 3/6/2004 

 6 12/17/2004 12/22/2004 

 2 3/5/2005 3/6/2005 

 1 3/8/2005 3/8/2005 

 2 3/15/2005 3/16/2005 

 1 4/12/2005 4/12/2005 

 1 5/13/2005 5/13/2005 

 2 1/1/2007 1/2/2007 

 1 1/12/2007 1/12/2007 

 6 2/14/2007 2/19/2007 

 2 3/16/2007 3/17/2007 

 4 4/10/2007 4/13/2007 

 13 11/26/2008 12/8/2008 

Three or more sequential values 5 12/2/1999 12/11/1999 

 3 12/24/1999 12/26/1999 

 15 1/2/2000 1/16/2000 

 4 2/2/2000 2/5/2000 

 2 2/7/2000 2/8/2000 
 APPENDIX COD, Attachment 2 

4 

Estimated Values Indicated by: Number of Days Excluded Start Date End Date 

 2 3/24/2000 3/25/2000 

 4 6/8/2001 6/11/2001 

 3 6/16/2001 6/18/2001 

 2 6/23/2001 6/24/2001 

 2 1/16/2002 1/17/2002 

 2 3/23/2002 3/24/2002 

 2 6/1/2002 6/2/2002 

 3 6/9/2002 6/11/2002 

 2 1/4/2003 1/5/2003 

 6 12/17/2004 12/22/2004 

 2 3/5/2005 3/6/2005 

 2 3/15/2005 3/16/2005 

 2 2/10/2006 2/11/2006 

 2 3/22/2006 3/23/2006 

 2 3/29/2006 3/30/2006 

 3 4/14/2006 4/16/2006 

 6 2/14/2007 2/19/2007 

 2 3/11/2007 3/12/2007 

 4 2/3/2008 2/6/2008 

 14 11/25/2008 12/8/2008 

 
APPENDIX COD, Attachment 3 

1 

APPENDIX COD, Attachment 3 

Listing of Daily Values Used As the Basis of the COD Limitations 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

12/1/1999 20 20 

12/12/1999 57 52 

12/13/1999 63 59 

12/14/1999 65 66 

12/15/1999 54 48 

12/16/1999 16 12 

12/17/1999 10 11 

12/19/1999 1 2 

12/20/1999 11 3 

12/21/1999 18 1 

12/22/1999 13 2 

12/23/1999 4 3 

12/27/1999 2 2 

12/28/1999 3 11 

12/29/1999 4 24 

12/30/1999 3 26 

1/1/2000 10 11 

1/2/2000 10 

1/3/2000 2 

1/17/2000 39 12 

1/18/2000 2 2 

1/19/2000 13 2 

1/20/2000 39 51 

1/21/2000 7 37 

1/22/2000 12 2 

1/23/2000 13 12 

1/24/2000 5 6 

1/25/2000 7 37 

1/26/2000 22 20 

1/27/2000 7 37 

1/28/2000 2 6 

1/29/2000 5 2 

1/30/2000 3 11 

1/31/2000 26 2 

2/1/2000 28 37 

2/2/2000 25 

2/3/2000 35 

2/4/2000 30 

2/5/2000 15 

2/6/2000 12 27 

2/7/2000 25 
APPENDIX COD, Attachment 3 

2 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

2/8/2000 20 

3/12/2000 30 55 

3/13/2000 15 35 

3/14/2000 9 2 

3/15/2000 109 29 

3/16/2000 326 33 

3/17/2000 206 16 

3/18/2000 270 4 

3/19/2000 103 31 

3/20/2000 126 2 

3/21/2000 212 30 

3/22/2000 97 26 

3/23/2000 315 93 

3/26/2000 47 45 

3/27/2000 44 49 

3/28/2000 38 37 

3/29/2000 15 5 

3/30/2000 2 10 

3/31/2000 7 7 

4/1/2000 9 3 

4/2/2000 7 4 

4/3/2000 51 7 

4/4/2000 2 4 

4/5/2000 35 7 

4/6/2000 2 9 

4/7/2000 10 

4/8/2000 3 

4/10/2000 3 8 

4/11/2000 14 11 

4/12/2000 23 9 

4/13/2000 11 7 

4/14/2000 11 13 

4/15/2000 13 4 

4/16/2000 5 26 

4/17/2000 2 12 

4/18/2000 11 8 

4/19/2000 27 14 

4/20/2000 26 11 

4/21/2000 8 11 

4/22/2000 4 12 

4/23/2000 4 12 

4/24/2000 16 7 

4/25/2000 11 20 

4/26/2000 50 11 

4/27/2000 25 9 
APPENDIX COD, Attachment 3 

3 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

4/28/2000 13 32 

4/29/2000 19 86 

4/30/2000 14 30 

5/1/2000 10 9 

5/2/2000 14 20 

5/3/2000 19 13 

5/4/2000 12 7 

5/5/2000 30 9 

5/6/2000 11 20 

5/7/2000 46 43 

5/8/2000 53 37 

5/9/2000 20 2 

5/10/2000 17 2 

5/11/2000 17 5 

5/12/2000 35 12 

5/13/2000 18 22 

5/14/2000 9 16 

5/15/2000 18 22 

5/16/2000 23 9 

5/17/2000 12 2 

5/18/2000 19 14 

5/19/2000 4 60 

5/20/2000 9 8 

5/21/2000 7 14 

5/22/2000 9 8 

5/23/2000 11 1 

5/24/2000 11 2 

5/25/2000 9 6 

5/26/2000 32 31 

5/27/2000 16 16 

5/28/2000 48 36 

5/29/2000 31 15 

5/30/2000 23 8 

5/31/2000 9 12 

6/1/2000 11 23 

6/2/2000 10 16 

6/3/2000 16 4 

6/4/2000 11 12 

6/5/2000 14 13 

6/6/2000 15 2 

6/7/2000 19 4 

6/8/2000 8 2 

6/9/2000 53 9 

6/10/2000 22 12 

6/11/2000 23 20 
APPENDIX COD, Attachment 3 

4 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

6/12/2000 2 13 

6/13/2000 16 5 

6/14/2000 27 11 

6/15/2000 7 8 

6/16/2000 8 12 

6/17/2000 22 19 

6/18/2000 18 19 

6/19/2000 2 2 

6/20/2000 26 18 

6/21/2000 19 17 

6/22/2000 2 2 

6/23/2000 3 2 

6/24/2000 4 3 

6/25/2000 3 2 

6/26/2000 1 3 

6/27/2000 6 3 

6/28/2000 87 71 

6/29/2000 2 3 

2/23/2001 140 168 

2/24/2001 108 122 

2/25/2001 82 50 

2/26/2001 104 114 

2/27/2001 75 68 

2/28/2001 92 90 

3/1/2001 276 232 

3/2/2001 118 110 

3/3/2001 73 93 

3/4/2001 132 110 

3/5/2001 102 82 

3/6/2001 82 

3/7/2001 63 78 

3/8/2001 58 127 

3/9/2001 88 74 

3/10/2001 80 69 

3/11/2001 288 64 

3/12/2001 575 92 

3/13/2001 91 52 

3/14/2001 63 75 

3/15/2001 36 40 

3/16/2001 47 61 

3/17/2001 57 54 

3/18/2001 59 56 

3/19/2001 104 105 

3/21/2001 105 

3/22/2001 129 393 
APPENDIX COD, Attachment 3 

5 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

3/23/2001 73 60 

3/24/2001 103 55 

3/25/2001 88 59 

3/26/2001 74 45 

3/27/2001 115 62 

3/28/2001 53 43 

3/29/2001 66 50 

3/30/2001 252 94 

3/31/2001 357 288 

4/1/2001 98 66 

4/2/2001 208 72 

4/3/2001 66 56 

4/4/2001 67 56 

4/5/2001 79 64 

4/6/2001 74 57 

4/7/2001 74 51 

4/8/2001 64 53 

4/9/2001 70 58 

4/10/2001 101 62 

4/11/2001 63 56 

4/12/2001 104 84 

4/13/2001 86 74 

4/14/2001 69 80 

4/15/2001 81 64 

4/16/2001 73 66 

4/17/2001 64 63 

4/18/2001 68 57 

4/19/2001 65 63 

4/20/2001 80 94 

4/21/2001 64 57 

4/22/2001 91 86 

4/23/2001 64 63 

4/24/2001 61 61 

4/25/2001 71 62 

4/26/2001 79 74 

4/27/2001 71 52 

4/28/2001 44 46 

4/29/2001 51 44 

4/30/2001 49 50 

5/1/2001 39 39 

5/2/2001 43 43 

5/3/2001 62 55 

5/4/2001 135 237 

5/5/2001 75 54 

5/6/2001 41 
APPENDIX COD, Attachment 3 

6 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

5/7/2001 75 60 

5/8/2001 72 62 

5/9/2001 67 58 

5/10/2001 64 47 

5/11/2001 58 53 

5/12/2001 45 52 

5/13/2001 53 58 

5/14/2001 60 36 

5/15/2001 50 43 

5/16/2001 48 46 

5/17/2001 51 50 

5/18/2001 38 27 

5/19/2001 37 41 

5/20/2001 49 39 

5/21/2001 48 35 

5/22/2001 34 29 

5/23/2001 48 35 

5/24/2001 33 44 

5/25/2001 31 29 

5/26/2001 13 32 

5/27/2001 26 21 

5/28/2001 26 21 

5/29/2001 22 20 

5/30/2001 23 21 

5/31/2001 19 

6/1/2001 11 

6/2/2001 2 15 

6/3/2001 7 15 

6/4/2001 23 11 

6/5/2001 30 27 

6/6/2001 17 14 

6/7/2001 37 33 

6/12/2001 25 35 

6/13/2001 35 29 

6/14/2001 27 50 

6/15/2001 30 34 

6/19/2001 32 27 

6/20/2001 23 19 

6/21/2001 26 25 

6/22/2001 28 22 

6/25/2001 27 34 

6/26/2001 47 36 

6/27/2001 28 26 

6/28/2001 27 30 

6/29/2001 35 29 
APPENDIX COD, Attachment 3 

7 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

12/16/2001 75 75 

12/17/2001 34 41 

12/18/2001 48 43 

12/19/2001 37 43 

12/20/2001 39 44 

12/21/2001 30 36 

12/22/2001 39 37 

12/23/2001 34 35 

12/24/2001 25 26 

12/25/2001 31 36 

12/26/2001 27 29 

12/27/2001 28 29 

12/28/2001 38 32 

12/29/2001 33 35 

12/30/2001 26 24 

12/31/2001 34 79 

1/1/2002 37 36 

1/2/2002 37 36 

1/3/2002 35 37 

1/4/2002 38 39 

1/5/2002 28 41 

1/6/2002 33 35 

1/8/2002 37 28 

1/9/2002 32 21 

1/10/2002 42 44 

1/11/2002 36 33 

1/12/2002 39 41 

1/13/2002 39 31 

1/14/2002 44 30 

1/15/2002 34 27 

1/16/2002 32 

1/17/2002 34 

1/18/2002 22 37 

1/19/2002 30 31 

1/21/2002 26 38 

1/22/2002 24 27 

1/23/2002 38 29 

1/24/2002 27 24 

1/25/2002 25 24 

1/26/2002 22 18 

1/27/2002 22 12 

1/28/2002 24 22 

1/30/2002 21 19 

1/31/2002 25 28 

2/1/2002 9 12 
APPENDIX COD, Attachment 3 

8 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

2/2/2002 157 168 

2/3/2002 54 36 

2/4/2002 54 35 

2/5/2002 41 29 

2/6/2002 36 30 

2/10/2002 37 35 

2/11/2002 28 39 

2/12/2002 65 64 

2/13/2002 34 48 

2/14/2002 60 48 

2/15/2002 45 49 

2/16/2002 47 40 

2/17/2002 55 47 

2/18/2002 53 57 

2/19/2002 49 51 

2/20/2002 63 54 

2/21/2002 50 51 

2/22/2002 51 53 

2/23/2002 76 47 

2/24/2002 46 51 

2/25/2002 45 56 

2/26/2002 63 63 

2/27/2002 76 54 

2/28/2002 61 67 

3/1/2002 72 71 

3/2/2002 71 72 

3/3/2002 63 67 

3/4/2002 62 62 

3/5/2002 70 75 

3/6/2002 71 68 

3/7/2002 71 91 

3/8/2002 73 77 

3/9/2002 61 59 

3/10/2002 66 67 

3/11/2002 78 73 

3/12/2002 92 67 

3/13/2002 80 65 

3/14/2002 81 55 

3/15/2002 83 57 

3/16/2002 71 59 

3/17/2002 78 64 

3/18/2002 68 57 

3/19/2002 63 65 

3/20/2002 72 57 

3/21/2002 62 60 
APPENDIX COD, Attachment 3 

9 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

3/22/2002 64 61 

3/23/2002 73 

3/24/2002 72 

3/25/2002 65 62 

3/26/2002 73 67 

3/27/2002 64 59 

3/28/2002 57 48 

3/29/2002 64 49 

3/30/2002 57 50 

3/31/2002 53 50 

4/1/2002 62 47 

4/2/2002 77 61 

4/3/2002 69 49 

4/4/2002 57 53 

4/5/2002 61 46 

4/6/2002 60 61 

4/7/2002 37 28 

4/8/2002 58 28 

4/9/2002 53 36 

4/10/2002 46 27 

4/11/2002 45 38 

4/12/2002 36 30 

4/13/2002 31 27 

4/14/2002 29 25 

4/15/2002 31 27 

4/16/2002 29 31 

4/17/2002 32 26 

4/18/2002 36 28 

4/19/2002 22 31 

4/20/2002 119 78 

4/21/2002 37 39 

4/22/2002 52 56 

4/23/2002 42 35 

4/24/2002 26 22 

4/25/2002 19 23 

4/26/2002 25 20 

4/27/2002 28 25 

4/28/2002 27 22 

4/29/2002 22 31 

4/30/2002 27 10 

5/1/2002 64 26 

5/2/2002 21 21 

5/3/2002 23 22 

5/4/2002 18 24 

5/5/2002 28 14 
APPENDIX COD, Attachment 3 

10 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

5/6/2002 29 32 

5/7/2002 23 16 

5/8/2002 24 17 

5/9/2002 35 22 

5/10/2002 37 28 

5/11/2002 41 27 

5/12/2002 28 27 

5/13/2002 38 26 

5/14/2002 31 29 

5/15/2002 35 24 

5/16/2002 25 15 

5/17/2002 32 27 

5/18/2002 25 19 

5/19/2002 25 25 

5/20/2002 27 22 

5/21/2002 28 27 

5/22/2002 27 22 

5/23/2002 31 23 

5/24/2002 22 20 

5/25/2002 27 

5/26/2002 27 22 

5/27/2002 27 23 

5/28/2002 40 28 

5/29/2002 31 25 

5/30/2002 26 23 

5/31/2002 17 16 

6/3/2002 33 34 

6/4/2002 24 22 

6/5/2002 25 20 

6/6/2002 22 20 

6/7/2002 24 18 

6/8/2002 22 20 

6/12/2002 50 71 

6/13/2002 49 68 

11/25/2002 20 41 

11/26/2002 38 43 

11/27/2002 25 25 

11/28/2002 23 29 

11/29/2002 32 37 

11/30/2002 41 36 

12/1/2002 29 36 

12/2/2002 40 34 

12/3/2002 72 50 

12/4/2002 59 52 

12/5/2002 59 65 
APPENDIX COD, Attachment 3 

11 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

12/6/2002 23 28 

12/7/2002 36 38 

12/8/2002 36 33 

12/9/2002 45 37 

12/10/2002 47 33 

12/11/2002 48 41 

12/12/2002 32 26 

12/13/2002 48 46 

12/14/2002 40 30 

12/15/2002 27 29 

12/16/2002 36 38 

12/17/2002 46 48 

12/18/2002 48 38 

12/19/2002 57 43 

12/20/2002 59 39 

12/21/2002 65 40 

12/22/2002 46 39 

12/23/2002 37 27 

12/24/2002 53 44 

12/25/2002 64 39 

12/27/2002 31 30 

12/28/2002 39 32 

12/29/2002 55 54 

12/30/2002 50 39 

12/31/2002 50 39 

1/1/2003 36 33 

1/2/2003 41 36 

1/3/2003 54 55 

1/6/2003 29 28 

1/7/2003 31 39 

1/8/2003 51 41 

1/9/2003 48 26 

1/10/2003 45 34 

1/11/2003 45 71 

1/12/2003 69.5 43.5 

1/13/2003 45 71 

1/14/2003 57 47 

1/15/2003 75 48 

1/16/2003 77 57 

1/17/2003 79 54 

1/18/2003 64 55 

1/19/2003 37 54 

1/20/2003 30 41 

1/21/2003 86 49 

1/22/2003 69 49 
APPENDIX COD, Attachment 3 

12 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

1/23/2003 46 48 

1/24/2003 58 57 

1/25/2003 70 55 

1/26/2003 40 38 

1/28/2003 31 55 

1/29/2003 53 54 

1/30/2003 65 48 

1/31/2003 73 56 

2/4/2003 104 56 

2/5/2003 87 57 

2/6/2003 73 57 

2/7/2003 47 46 

2/9/2003 49 42 

2/10/2003 57 53 

2/11/2003 94 61 

2/12/2003 72 49 

2/13/2003 61 49 

2/14/2003 60 45 

2/15/2003 57 44 

2/16/2003 73 58 

2/17/2003 71 53 

2/18/2003 68 57 

2/19/2003 55 46 

2/20/2003 66 35 

2/21/2003 101 74 

2/22/2003 73 66 

2/23/2003 55 33 

2/24/2003 74 45 

2/25/2003 91 63 

2/26/2003 76 58 

2/27/2003 106 60 

2/28/2003 121 111 

3/1/2003 118 83 

3/2/2003 120 66 

3/3/2003 104 49 

3/4/2003 105 51 

3/5/2003 86 37 

3/6/2003 95 40 

3/7/2003 118 65 

3/8/2003 111 54 

3/9/2003 110 48 

3/10/2003 113 59 

3/11/2003 137 69 

3/12/2003 136 55 

3/13/2003 127 55 
APPENDIX COD, Attachment 3 

13 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

3/14/2003 114 51 

3/15/2003 137 68 

3/16/2003 91 48 

3/17/2003 107 68 

3/18/2003 107 68 

3/19/2003 82 63 

3/20/2003 70 50 

3/21/2003 64 35 

3/22/2003 97 49 

3/23/2003 76 48 

3/24/2003 93 51 

3/25/2003 105 55 

3/26/2003 77 83 

3/27/2003 56 42 

3/28/2003 92 41 

3/29/2003 85 51 

3/30/2003 67 42 

3/31/2003 65 39 

4/1/2003 70 39 

4/2/2003 65 40 

4/3/2003 75 48 

4/4/2003 66 44 

4/8/2003 70 38 

4/9/2003 93 56 

4/10/2003 151 53 

4/11/2003 62 40 

4/12/2003 91 64 

4/13/2003 103 42 

4/14/2003 94 97 

4/15/2003 133 73 

4/16/2003 63 

4/17/2003 93 90 

4/18/2003 96 50 

4/19/2003 120 69 

4/20/2003 93 47 

4/21/2003 108 56 

4/22/2003 154 94 

4/23/2003 127 85 

4/24/2003 120 50 

4/25/2003 157 84 

4/26/2003 126 70 

4/27/2003 113 48 

4/28/2003 121 59 

4/29/2003 161 69 

4/30/2003 135 83 
APPENDIX COD, Attachment 3 

14 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

5/1/2003 161 69 

5/2/2003 90 62 

5/3/2003 134 69 

5/4/2003 116 73 

5/5/2003 130 74 

5/6/2003 138 80 

5/7/2003 156 64 

5/8/2003 154 70 

5/9/2003 124 51 

5/10/2003 136 67 

5/11/2003 136 59 

5/12/2003 138 69 

5/13/2003 164 72 

5/14/2003 158 68 

5/15/2003 138 60 

5/16/2003 116 70 

5/17/2003 264 

5/18/2003 685 

5/19/2003 460 95 

5/20/2003 655 86 

5/21/2003 178 83 

5/22/2003 290 101 

5/23/2003 102 72 

5/24/2003 80 64 

5/25/2003 78 56 

5/26/2003 110 65 

5/27/2003 110 65 

5/28/2003 86 58 

5/29/2003 68 48 

5/30/2003 71 64 

5/31/2003 77 43 

6/1/2003 54 41 

6/2/2003 59 41 

6/3/2003 63 36 

6/4/2003 64 40 

6/5/2003 58 43 

6/6/2003 58 43 

12/5/2003 1 

12/6/2003 51 71 

12/7/2003 38 59 

12/8/2003 34 42 

12/9/2003 27 57 

12/10/2003 24 54 

12/11/2003 15 30 

12/12/2003 9 37 
APPENDIX COD, Attachment 3 

15 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

12/14/2003 8 45 

12/15/2003 3 27 

12/16/2003 50 19 

12/17/2003 41 24 

12/18/2003 33 9 

12/19/2003 122 2 

12/20/2003 278 2 

12/21/2003 2 14 

12/22/2003 5 27 

12/23/2003 26 47 

12/24/2003 22 52 

12/25/2003 23 75 

12/26/2003 23 67 

12/27/2003 32 75 

12/28/2003 20 24 

12/29/2003 27 26 

12/30/2003 26 28 

12/31/2003 29 39 

1/1/2004 19 40 

1/2/2004 13 28 

1/3/2004 690 36 

1/4/2004 74 41 

1/5/2004 33 35 

1/6/2004 267 40 

1/7/2004 42 38 

1/8/2004 387 37 

1/9/2004 225 32 

1/10/2004 80 46 

1/11/2004 30 46 

1/12/2004 27 28 

1/13/2004 28 35 

1/14/2004 39 47 

1/15/2004 36 43 

1/16/2004 52 40 

1/17/2004 25 38 

1/18/2004 39 42 

1/19/2004 37 41 

1/20/2004 72 57 

1/21/2004 174 83 

1/22/2004 145 100 

1/23/2004 44 42 

1/24/2004 23 63 

1/25/2004 58 54 

1/26/2004 42 51 

1/27/2004 83 68 
APPENDIX COD, Attachment 3 

16 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

1/29/2004 62 78 

1/30/2004 22 43 

1/31/2004 62 78 

2/1/2004 41 48 

2/2/2004 47 58 

2/3/2004 220 103 

2/4/2004 20 51 

2/5/2004 48 54 

2/6/2004 27 49 

2/8/2004 435 74 

2/9/2004 453 49 

2/10/2004 77 123 

2/11/2004 25 56 

2/12/2004 23 66 

2/13/2004 25 61 

2/15/2004 52 84 

2/16/2004 25 61 

2/17/2004 37 67 

2/18/2004 52 84 

2/19/2004 23 56 

2/20/2004 40 62 

2/22/2004 21 55 

2/23/2004 50 95 

2/24/2004 70 64 

2/25/2004 43 109 

2/26/2004 57 52 

2/27/2004 21 64 

2/29/2004 24 58 

3/1/2004 61 103 

3/2/2004 114 69 

3/3/2004 46 62 

3/4/2004 196 96 

3/5/2004 92 70 

3/7/2004 60 78 

3/8/2004 55 84 

3/9/2004 45 78 

3/10/2004 102 94 

3/11/2004 90 114 

3/12/2004 88 210 

3/13/2004 61 76 

3/14/2004 65 85 

3/15/2004 69 100 

3/16/2004 316 124 

3/17/2004 699 118 

3/18/2004 123 126 
APPENDIX COD, Attachment 3 

17 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

3/19/2004 80 94 

3/20/2004 194 116 

3/21/2004 92 43 

3/22/2004 85 64 

3/23/2004 62 84 

3/24/2004 95 74 

3/25/2004 89 97 

3/26/2004 61 68 

3/27/2004 73 91 

3/28/2004 81 95 

3/29/2004 138 106 

3/30/2004 58 50 

3/31/2004 66 92 

4/1/2004 61 68 

4/2/2004 46 71 

4/3/2004 66 78 

4/4/2004 59 93 

4/5/2004 56 77 

4/6/2004 65 79 

4/7/2004 56 65 

4/8/2004 82 75 

4/9/2004 51 73 

4/10/2004 25 69 

4/11/2004 61 79 

4/12/2004 48 123 

4/13/2004 35 69 

4/14/2004 35 64 

4/15/2004 59 69 

4/16/2004 59 69 

4/17/2004 44 57 

4/18/2004 51 62 

4/19/2004 71 58 

4/20/2004 60 60 

4/21/2004 68 60 

4/22/2004 61 73 

4/23/2004 40 62 

4/24/2004 93 39 

4/25/2004 93 39 

4/26/2004 47 48 

4/27/2004 38 55 

4/28/2004 31 46 

4/29/2004 21 50 

4/30/2004 42 102 

5/1/2004 26 36 

5/2/2004 25 41 
APPENDIX COD, Attachment 3 

18 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

5/3/2004 12 39 

5/4/2004 30 57 

5/5/2004 15 38 

5/6/2004 100 168 

12/11/2004 30 30 

12/12/2004 31 27 

12/13/2004 11 3 

12/14/2004 10 10 

12/15/2004 2 

12/16/2004 5 

12/23/2004 13 31 

12/24/2004 2 13 

12/25/2004 12 30 

12/26/2004 9 24 

12/27/2004 11 27 

12/28/2004 12 50 

12/29/2004 11 20 

12/30/2004 7 13 

12/31/2004 9 13 

1/1/2005 124 26 

1/2/2005 63 2 

1/3/2005 2 18 

1/4/2005 275 725 

1/5/2005 2 30 

1/6/2005 24 70 

1/7/2005 12 53 

1/8/2005 16 48 

1/9/2005 12 58 

1/10/2005 14 45 

1/11/2005 13 40 

1/12/2005 8 43 

1/13/2005 14 162 

1/14/2005 17 44 

1/15/2005 14 63 

1/16/2005 10 58 

1/17/2005 5 56 

1/18/2005 19 108 

1/19/2005 15 26 

1/20/2005 30 24 

1/21/2005 33 34 

1/22/2005 37 41 

1/23/2005 21 40 

1/24/2005 15 52 

1/25/2005 12 40 

1/26/2005 13 66 
APPENDIX COD, Attachment 3 

19 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

1/27/2005 39 186 

1/28/2005 19 112 

1/29/2005 25 98 

1/30/2005 24 73 

1/31/2005 20 72 

2/1/2005 24 72 

2/2/2005 25 79 

2/3/2005 35 196 

2/4/2005 38 360 

2/5/2005 24 230 

2/6/2005 23 30 

2/7/2005 32 105 

2/8/2005 26 195 

2/9/2005 26 195 

2/10/2005 25 80 

2/11/2005 32 93 

2/12/2005 32 133 

2/13/2005 41 102 

2/14/2005 40 94 

2/15/2005 33 118 

2/16/2005 38 238 

2/17/2005 30 175 

2/18/2005 33 216 

2/19/2005 29 136 

2/20/2005 25 178 

2/21/2005 31 132 

2/22/2005 24 140 

2/23/2005 62 170 

2/24/2005 44 148 

2/25/2005 42 156 

2/26/2005 52 156 

2/27/2005 33 124 

2/28/2005 35 124 

3/1/2005 33 110 

3/2/2005 27 98 

3/3/2005 39 94 

3/4/2005 28 82 

3/7/2005 81 

3/9/2005 30 112 

3/10/2005 28 82 

3/11/2005 30 82 

3/12/2005 25 83 

3/13/2005 24 81 

3/14/2005 18 80 

3/17/2005 58 104 
APPENDIX COD, Attachment 3 

20 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

3/18/2005 105 116 

3/19/2005 164 74 

3/20/2005 150 62 

3/21/2005 60 96 

3/22/2005 49 94 

3/23/2005 54 82 

3/24/2005 86 

3/25/2005 89 

3/26/2005 44 92 

3/27/2005 54 86 

3/28/2005 55 92 

3/29/2005 28 89 

3/30/2005 34 86 

3/31/2005 45 93 

4/1/2005 37 100 

4/2/2005 33 97 

4/3/2005 31 80 

4/4/2005 36 75 

4/5/2005 32 76 

4/6/2005 32 76 

4/7/2005 35 70 

4/8/2005 30 73 

4/9/2005 34 71 

4/10/2005 27 66 

4/11/2005 14 59 

4/13/2005 22 65 

4/14/2005 36 67 

4/15/2005 21 74 

4/16/2005 13 74 

4/17/2005 64 85 

4/18/2005 36 28 

4/19/2005 39 97 

4/20/2005 25 87 

4/21/2005 19 93 

4/22/2005 25 60 

4/23/2005 24 58 

4/24/2005 24 59 

4/25/2005 23 61 

4/26/2005 21 65 

4/27/2005 23 63 

4/28/2005 15 69 

4/29/2005 14 58 

4/30/2005 24 71 

5/1/2005 25 69 

5/2/2005 30 76 
APPENDIX COD, Attachment 3 

21 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

5/3/2005 20 83 

5/4/2005 28 80 

5/5/2005 43 82 

5/6/2005 34 96 

5/7/2005 24 84 

5/8/2005 16 76 

5/9/2005 20 71 

5/10/2005 18 70 

5/11/2005 14 81 

5/12/2005 18 94 

5/14/2005 43 104 

5/15/2005 15 73 

5/16/2005 12 74 

5/17/2005 12 74 

11/30/2005 30 30 

12/1/2005 39 65 

12/2/2005 65 

12/3/2005 33 66 

12/4/2005 39 61 

12/5/2005 24 57 

12/6/2005 34 143 

12/7/2005 55 52 

12/8/2005 61 84 

12/9/2005 162 275 

12/10/2005 21 36 

12/11/2005 18 99 

12/12/2005 102 

12/13/2005 22 

12/14/2005 15 29 

12/15/2005 20 28 

12/16/2005 54 144 

12/17/2005 26 40 

12/18/2005 50 

12/19/2005 55 

12/20/2005 34 86 

12/21/2005 24 108 

12/22/2005 22 94 

12/23/2005 28 104 

1/5/2006 30 201 

1/6/2006 28 90 

1/7/2006 38 66 

1/8/2006 25 71 

1/9/2006 30 91 

2/4/2006 30 94 

2/5/2006 29 74 
APPENDIX COD, Attachment 3 

22 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

2/6/2006 53 108 

2/7/2006 56 94 

2/8/2006 31 90 

2/9/2006 48 96 

2/10/2006 19 

2/12/2006 25 82 

2/13/2006 37 110 

2/14/2006 59 112 

2/15/2006 40 76 

2/16/2006 27 116 

2/17/2006 42 84 

2/18/2006 32 80 

2/19/2006 28 78 

2/20/2006 9 76 

2/21/2006 34 86 

2/22/2006 24 62 

2/23/2006 41 86 

2/24/2006 31 86 

2/25/2006 35 96 

2/26/2006 35 88 

2/27/2006 33 75 

2/28/2006 33 80 

3/1/2006 36 96 

3/2/2006 40 90 

3/3/2006 93 

3/4/2006 93 

3/5/2006 35 68 

3/6/2006 20 76 

3/7/2006 76 

3/8/2006 39 87 

3/9/2006 32 81 

3/10/2006 38 89 

3/11/2006 24 72 

3/12/2006 22 74 

3/13/2006 31 71 

3/14/2006 31 72 

3/15/2006 26 66 

3/16/2006 20 68 

3/17/2006 32 71 

3/18/2006 27 70 

3/19/2006 25 59 

3/20/2006 22 53 

3/21/2006 33 79 

3/24/2006 38 60 

3/25/2006 28 68 
APPENDIX COD, Attachment 3 

23 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

3/26/2006 28 68 

3/27/2006 14 61 

3/28/2006 25 72 

3/29/2006 23 

3/30/2006 23 

3/31/2006 17 66 

4/1/2006 21 70 

4/2/2006 17 69 

4/3/2006 14 67 

4/4/2006 21 71 

4/5/2006 25 58 

4/6/2006 41 66 

4/7/2006 19 52 

4/8/2006 26 67 

4/9/2006 21 41 

4/10/2006 8 60 

4/11/2006 8 60 

4/12/2006 17 23 

4/13/2006 8 60 

4/17/2006 61 43 

4/18/2006 37 40 

4/19/2006 46 44 

1/1/2007 30 

1/2/2007 30 

1/3/2007 6 70 

1/4/2007 18 64 

1/5/2007 15 46 

1/6/2007 13 32 

1/7/2007 10 25 

1/8/2007 5 13 

1/9/2007 2 18 

1/10/2007 2 22 

1/11/2007 2 13 

1/13/2007 12 12 

1/14/2007 1 19 

4/4/2007 28 93 

4/5/2007 28 48 

4/6/2007 31 42 

4/7/2007 34 81 

4/8/2007 25 96 

4/9/2007 26 86 

4/14/2007 58 41 

4/15/2007 16 87 

4/16/2007 31 44 

4/17/2007 94 126 
APPENDIX COD, Attachment 3 

24 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

4/18/2007 33 146 

4/19/2007 25 128 

4/20/2007 24 144 

4/21/2007 28 148 

4/22/2007 31 130 

4/23/2007 28 120 

4/24/2007 26 122 

4/25/2007 17 92 

4/26/2007 19 100 

4/27/2007 17 96 

4/28/2007 25 32 

4/29/2007 17 120 

4/30/2007 14 78 

5/1/2007 21 140 

5/2/2007 32 16 

5/3/2007 34 74 

5/4/2007 26 114 

5/5/2007 29 82 

5/6/2007 42 68 

5/7/2007 12 86 

5/8/2007 3 28 

5/9/2007 3 28 

5/10/2007 11 22 

5/11/2007 17 30 

5/12/2007 12 42 

5/13/2007 12 48 

5/14/2007 8 18 

5/15/2007 5 47 

5/16/2007 10 20 

5/17/2007 8 10 

5/18/2007 1 32 

5/19/2007 31 

5/20/2007 31 

5/21/2007 4 15 

5/22/2007 13 31 

5/23/2007 8 43 

5/24/2007 5 36 

5/25/2007 4 38 

5/26/2007 47 47 

5/27/2007 108 2 

5/28/2007 136 90 

1/1/2008 100 

1/4/2008 122 

1/5/2008 144 

1/6/2008 89 
APPENDIX COD, Attachment 3 

25 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

1/7/2008 28 

1/8/2008 18 

1/9/2008 1042 

1/10/2008 433 

1/11/2008 40 

1/12/2008 66 

1/13/2008 34 

1/14/2008 31 

1/15/2008 34 

1/16/2008 34 

1/17/2008 45 

1/18/2008 88 

1/19/2008 85 

1/20/2008 64 

1/21/2008 44 

1/22/2008 47 

1/23/2008 48 

1/24/2008 31 

1/25/2008 50 

1/26/2008 51 

1/27/2008 71 

1/28/2008 34 

1/29/2008 35 

1/30/2008 33 

1/31/2008 51 

2/1/2008 52 

3/4/2008 43 54 

3/5/2008 45 47 

3/6/2008 54 50 

3/7/2008 59 48 

3/8/2008 41 30 

3/9/2008 48 42 

3/10/2008 40 40 

3/11/2008 51 34 

3/12/2008 77 40 

3/13/2008 70 52 

3/14/2008 34 50 

3/15/2008 49 41 

3/16/2008 78 46 

3/17/2008 64 45 

3/18/2008 46 38 

3/19/2008 57 44 

3/20/2008 58 36 

3/21/2008 57 45 

3/22/2008 44 49 
APPENDIX COD, Attachment 3 

26 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

3/23/2008 60 46 

3/24/2008 55 43 

3/25/2008 40 30 

3/26/2008 41 32 

3/27/2008 51 40 

3/28/2008 47 39 

3/29/2008 51 37 

3/30/2008 47 44 

3/31/2008 46 39 

4/1/2008 35 29 

4/2/2008 40 34 

4/3/2008 48 34 

4/4/2008 39 28 

4/5/2008 45 35 

4/6/2008 44 34 

4/7/2008 34 35 

4/8/2008 53 39 

4/9/2008 52 46 

4/10/2008 50 46 

4/11/2008 47 37 

4/12/2008 47 41 

4/13/2008 63 58 

4/14/2008 43 35 

4/15/2008 42 26 

4/16/2008 41 33 

4/17/2008 23 26 

4/18/2008 39 36 

4/19/2008 34 36 

4/20/2008 47 37 

4/21/2008 65 40 

4/22/2008 45 41 

4/23/2008 39 36 

4/24/2008 54 26 

4/25/2008 34 27 

4/26/2008 26 20 

4/27/2008 29 33 

4/28/2008 30 27 

4/29/2008 21 18 

4/30/2008 32 33 

5/1/2008 27 26 

5/2/2008 27 33 

5/3/2008 29 30 

5/4/2008 28 37 

5/5/2008 28 37 

5/6/2008 29 28 
APPENDIX COD, Attachment 3 

27 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

5/7/2008 32 25 

5/8/2008 19 27 

5/9/2008 25 27 

5/10/2008 29 28 

5/11/2008 29 34 

5/12/2008 36 33 

5/13/2008 34 

5/14/2008 34 

5/15/2008 42 43 

5/16/2008 44 45 

5/17/2008 22 19 

5/18/2008 29 26 

5/19/2008 19 22 

5/20/2008 12 18 

5/21/2008 24 20 

5/22/2008 23 12 

5/23/2008 25 21 

5/24/2008 23 21 

5/25/2008 20 20 

5/26/2008 22 19 

5/27/2008 29 21 

5/28/2008 17 14 

5/29/2008 9 15 

5/30/2008 21 16 

5/31/2008 19 22 

6/1/2008 24 28 

6/2/2008 31 29 

6/3/2008 38 23 

6/4/2008 38 

6/5/2008 38 

6/6/2008 47 54 

6/7/2008 52 28 

6/8/2008 49 29 

6/9/2008 38 22 

12/12/2008 32 42 

12/13/2008 44 30 

12/14/2008 36 40 

12/15/2008 41 37 

12/16/2008 45 36 

12/17/2008 26 24 

12/18/2008 30 28 

12/19/2008 25 31 

12/20/2008 21 24 

12/21/2008 27 35 

12/22/2008 32 35 
APPENDIX COD, Attachment 3 

28 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

12/23/2008 35 29 

12/24/2008 27 30 

12/25/2008 674 282 

12/26/2008 116 46 

12/27/2008 23 37 

12/28/2008 27 31 

12/29/2008 23 23 

12/30/2008 29 24 

12/31/2008 39 32 

1/1/2009 31 23 

1/2/2009 49 31 

1/3/2009 53 29 

1/4/2009 37 26 

1/5/2009 31 23 

1/6/2009 30 38 

1/7/2009 45 37 

1/8/2009 27 22 

1/9/2009 20 22 

1/10/2009 28 30 

1/11/2009 35 21 

1/12/2009 33 24 

1/13/2009 41 40 

1/14/2009 33 24 

1/15/2009 23 25 

1/16/2009 20 45 

1/17/2009 28 46 

1/18/2009 16 12 

1/19/2009 28 18 

1/20/2009 30 30 

1/21/2009 27 32 

1/22/2009 30 50 

1/23/2009 29 41 

1/24/2009 43 34 

1/25/2009 48 44 

1/26/2009 46 45 

1/27/2009 77 53 

1/28/2009 24 25 

1/29/2009 51 24 

1/30/2009 41 24 

1/31/2009 56 36 

2/1/2009 28 39 

2/2/2009 28 30 

2/3/2009 39 24 

2/4/2009 38 23 

2/5/2009 25 27 
APPENDIX COD, Attachment 3 

29 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

2/6/2009 15 30 

2/7/2009 16 38 

2/8/2009 27 37 

2/9/2009 24 23 

2/10/2009 26 32 

2/11/2009 25 28 

2/12/2009 43 31 

2/13/2009 35 46 

2/14/2009 39 42 

2/15/2009 46 42 

2/16/2009 36 43 

2/17/2009 36 53 

2/18/2009 51 44 

2/19/2009 38 39 

2/20/2009 38 43 

2/21/2009 15 27 

2/22/2009 29 38 

2/23/2009 32 36 

2/24/2009 40 45 

2/25/2009 53 52 

2/26/2009 45 47 

2/27/2009 68 73 

2/28/2009 58 57 

3/1/2009 50 43 

3/2/2009 53 44 

3/3/2009 41 33 

3/4/2009 67 44 

3/5/2009 51 61 

3/6/2009 33 28 

3/7/2009 62 50 

3/8/2009 75 67 

3/9/2009 31 47 

3/10/2009 49 44 

3/11/2009 37 47 

3/12/2009 46 54 

3/13/2009 36 46 

3/14/2009 56 23 

3/15/2009 54 44 

3/16/2009 60 61 

3/17/2009 27 51 

3/18/2009 40 19 

3/19/2009 45 46 

3/20/2009 37 43 

3/21/2009 41 43 

3/22/2009 39 40 
APPENDIX COD, Attachment 3 

30 

Date 

Concentrations (mg/L) 

Effluent 

ArprtR_101 ArprtR_102 

3/23/2009 35 42 

3/24/2009 32 37 

3/25/2009 30 33 

3/26/2009 26 30 

3/27/2009 20 31 

3/28/2009 30 48 

3/29/2009 39 38 

3/30/2009 38 45 

3/31/2009 20 46 

4/1/2009 26 37 

4/2/2009 28 34 

4/3/2009 34 42 

4/4/2009 53 56 

4/5/2009 60 58 

4/6/2009 43 47 

4/7/2009 30 36 

4/8/2009 38 34 

4/9/2009 34 32 

4/10/2009 28 25 

 
APPENDIX COD, Attachment 4 

1 

APPENDIX COD, Attachment 4 

Plots of the Daily Values Used As the Basis of the COD Limitations 

The following plots show the COD concentrations used as a basis for the limitations. There is one 

plot for each deicing season going from the fall to the following summer. The plots show the date, 

the influent concentration, the effluent concentration from unit R_101 (variable name ArprtR_101), 

and the effluent concentration from unit R_102 (variable name ArprtR_102). Concentrations are in 

mg/L and are shown using a logarithmic scale. 

 
APPENDIX COD, Attachment 4 

2 

Season99-Data Selected As Basis of Limitations

0.1

1

10

100

1000

10000

100000

11/15/1999 12/15/1999 1/15/2000 2/15/2000 3/15/2000 4/15/2000 5/15/2000 6/15/2000 7/15/2000

COD(mg/l)

ArprtR_101

ArprtR_102

Influent

Season00-Data Selected As Basis of Limitations

0.1

1

10

100

1000

10000

100000

11/15/2000 12/15/2000 1/15/2001 2/15/2001 3/15/2001 4/15/2001 5/15/2001 6/15/2001 7/15/2001

COD(mg/l)

ArprtR_101

ArprtR_102

Influent
APPENDIX COD, Attachment 4 

3 

Season01-Data Selected As Basis of Limitations

0.1

1

10

100

1000

10000

100000

11/15/2001 12/15/2001 1/15/2002 2/15/2002 3/15/2002 4/15/2002 5/15/2002 6/15/2002 7/15/2002

COD(mg/l)

ArprtR_101

ArprtR_102

Influent

Season02-Data Selected As Basis of Limitations

0.1

1

10

100

1000

10000

100000

11/15/2002 12/15/2002 1/15/2003 2/15/2003 3/15/2003 4/15/2003 5/15/2003 6/15/2003 7/15/2003

COD(mg/l)

ArprtR_101

ArprtR_102

Influent
APPENDIX COD, Attachment 4 

4 

Season03-Data Selected As Basis of Limitations

0.1

1

10

100

1000

10000

100000

11/15/2003 12/15/2003 1/15/2004 2/15/2004 3/15/2004 4/15/2004 5/15/2004 6/15/2004 7/15/2004

COD(mg/l)

ArprtR_101

ArprtR_102

Influent

Season04-Data Selected As Basis of Limitations

0.1

1

10

100

1000

10000

100000

11/15/2004 12/15/2004 1/15/2005 2/15/2005 3/15/2005 4/15/2005 5/15/2005 6/15/2005 7/15/2005

COD(mg/l)

ArprtR_101

ArprtR_102

Influent
APPENDIX COD, Attachment 4 

5 

Season05-Data Selected As Basis of Limitations

0.1

1

10

100

1000

10000

100000

11/15/2005 12/15/2005 1/15/2006 2/15/2006 3/15/2006 4/15/2006 5/15/2006 6/15/2006 7/15/2006

COD(mg/l)

ArprtR_101

ArprtR_102

Influent

Season06-Data Selected As Basis of Limitations

0.1

1

10

100

1000

10000

100000

11/15/2006 12/15/2006 1/15/2007 2/15/2007 3/15/2007 4/15/2007 5/15/2007 6/15/2007 7/15/2007

COD(mg/l)

ArprtR_101

ArprtR_102

Influent
APPENDIX COD, Attachment 4 

6 

Season07-Data Selected As Basis of Limitations

0.1

1

10

100

1000

10000

100000

11/15/2007 12/15/2007 1/15/2008 2/15/2008 3/15/2008 4/15/2008 5/15/2008 6/15/2008 7/15/2008

COD(mg/l)

ArprtR_101

ArprtR_102

Influent

Season08-Data Selected As Basis of Limitations

0.1

1

10

100

1000

10000

100000

11/15/2008 12/15/2008 1/15/2009 2/15/2009 3/15/2009 4/15/2009 5/15/2009 6/15/2009 7/15/2009

COD(mg/l)

ArprtR_101

ArprtR_102

Influent
APPENDIX COD, Attachment 5 

1 

APPENDIX COD, Attachment 5 

List of Weekly Averages (Calculated Using the Daily COD Values) Used to Calculate the 

Weekly Average Limitation. 

Week 

(MM/DD/YYY) 

ArprtR-101 ArprtR-102 

Number of daily values 

in weekly average

Weekly Average 

(mg/L)

Number of daily 

values in weekly 

average

Weekly 

Average 

(mg/L)

12/1/1999 1 20.0 1 20.0 

12/13/1999 5 41.6 5 39.2 

12/20/1999 4 11.5 4 2.3 

12/27/1999 4 3.0 4 15.8 

1/3/2000 1 2.0 0 

1/17/2000 5 20.0 5 20.8 

1/24/2000 5 8.6 5 21.2 

1/31/2000 5 28.8 2 19.5 

2/7/2000 2 22.5 0 

3/13/2000 5 133.0 5 23.0 

3/20/2000 4 187.5 4 37.8 

3/27/2000 5 21.2 5 21.6 

4/3/2000 4 22.5 5 7.4 

4/10/2000 5 12.4 5 9.6 

4/17/2000 5 14.8 5 11.2 

4/24/2000 5 23.0 5 15.8 

5/1/2000 5 17.0 5 11.6 

5/8/2000 5 28.4 5 11.6 

5/15/2000 5 15.2 5 21.4 

5/22/2000 5 14.4 5 9.6 

5/29/2000 5 16.8 5 14.8 

6/5/2000 5 21.8 5 6.0 

6/12/2000 5 12.0 5 9.8 

6/19/2000 5 10.4 5 8.2 

6/26/2000 4 24.0 4 20.0 

2/19/2001 1 140.0 1 168.0 

2/26/2001 5 133.0 5 122.8 

3/5/2001 4 77.8 5 88.6 

3/12/2001 5 162.4 5 64.0 

3/19/2001 3 102.0 4 165.8 

3/26/2001 5 112.0 5 58.8 

4/2/2001 5 98.8 5 61.0 

4/9/2001 5 84.8 5 66.8 

4/16/2001 5 70.0 5 68.6 

4/23/2001 5 69.2 5 62.4 

4/30/2001 5 65.6 5 84.8 

5/7/2001 5 67.2 5 56.0 

5/14/2001 5 49.4 5 40.4 

5/21/2001 5 38.8 5 34.4 
APPENDIX COD, Attachment 5 

2 

Week 

(MM/DD/YYY) 

ArprtR-101 ArprtR-102 

Number of daily values 

in weekly average

Weekly Average 

(mg/L)

Number of daily 

values in weekly 

average

Weekly 

Average 

(mg/L)

5/28/2001 3 23.7 5 18.4 

6/4/2001 4 26.8 4 21.3 

6/11/2001 4 29.3 4 37.0 

6/18/2001 4 27.3 4 23.3 

6/25/2001 5 32.8 5 31.0 

12/17/2001 5 37.6 5 41.4 

12/24/2001 5 29.8 5 30.4 

12/31/2001 5 36.2 5 45.4 

1/7/2002 4 36.8 4 31.5 

1/14/2002 5 33.2 3 31.3 

1/21/2002 5 28.0 5 28.4 

1/28/2002 4 19.8 4 20.3 

2/4/2002 3 43.7 3 31.3 

2/11/2002 5 46.4 5 49.6 

2/18/2002 5 53.2 5 53.2 

2/25/2002 5 63.4 5 62.2 

3/4/2002 5 69.4 5 74.6 

3/11/2002 5 82.8 5 63.4 

3/18/2002 5 65.8 5 60.0 

3/25/2002 5 64.6 5 57.0 

4/1/2002 5 65.2 5 51.2 

4/8/2002 5 47.6 5 31.8 

4/15/2002 5 30.0 5 28.6 

4/22/2002 5 32.8 5 31.2 

4/29/2002 5 31.4 5 22.0 

5/6/2002 5 29.6 5 23.0 

5/13/2002 5 32.2 5 24.2 

5/20/2002 5 27.0 5 22.8 

5/27/2002 5 28.2 5 23.0 

6/3/2002 5 25.6 5 22.8 

6/10/2002 2 49.5 2 69.5 

11/25/2002 5 27.6 5 35.0 

12/2/2002 5 50.6 5 45.8 

12/9/2002 5 44.0 5 36.6 

12/16/2002 5 49.2 5 41.2 

12/23/2002 4 46.3 4 35.0 

12/30/2002 5 46.2 5 40.4 

1/6/2003 5 40.8 5 33.6 

1/13/2003 5 66.6 5 55.4 

1/20/2003 5 57.8 5 48.8 

1/27/2003 4 55.5 4 53.3 

2/3/2003 4 77.8 4 54.0 

2/10/2003 5 68.8 5 51.4 

2/17/2003 5 72.2 5 53.0 
APPENDIX COD, Attachment 5 

3 

Week 

(MM/DD/YYY) 

ArprtR-101 ArprtR-102 

Number of daily values 

in weekly average

Weekly Average 

(mg/L)

Number of daily 

values in weekly 

average

Weekly 

Average 

(mg/L)

2/24/2003 5 93.6 5 67.4 

3/3/2003 5 101.6 5 48.4 

3/10/2003 5 125.4 5 57.8 

3/17/2003 5 86.0 5 56.8 

3/24/2003 5 84.6 5 54.4 

3/31/2003 5 68.2 5 42.0 

4/7/2003 4 94.0 4 46.8 

4/14/2003 4 104.0 5 74.6 

4/21/2003 5 133.2 5 73.8 

4/28/2003 5 133.6 5 68.4 

5/5/2003 5 140.4 5 67.8 

5/12/2003 5 142.8 5 67.8 

5/19/2003 5 337.0 5 87.4 

5/26/2003 5 89.0 5 60.0 

6/2/2003 5 60.4 5 40.6 

12/1/2003 0 1 1.0 

12/8/2003 5 21.8 5 44.0 

12/15/2003 5 49.8 5 16.2 

12/22/2003 5 19.8 5 53.6 

12/29/2003 5 22.8 5 32.2 

1/5/2004 5 190.8 5 36.4 

1/12/2004 5 36.4 5 38.6 

1/19/2004 5 94.4 5 64.6 

1/26/2004 4 52.3 4 60.0 

2/2/2004 5 72.4 5 63.0 

2/9/2004 5 120.6 5 71.0 

2/16/2004 5 35.4 5 66.0 

2/23/2004 5 48.2 5 76.8 

3/1/2004 5 101.8 5 80.0 

3/8/2004 5 76.0 5 116.0 

3/15/2004 5 257.4 5 112.4 

3/22/2004 5 78.4 5 77.4 

3/29/2004 5 73.8 5 77.4 

4/5/2004 5 62.0 5 73.8 

4/12/2004 5 47.2 5 78.8 

4/19/2004 5 60.0 5 62.6 

4/26/2004 5 35.8 5 60.2 

5/3/2004 4 39.3 4 75.5 

12/13/2004 2 10.5 4 5.0 

12/20/2004 2 7.5 2 22.0 

12/27/2004 5 10.0 5 24.6 

1/3/2005 5 63.0 5 179.2 

1/10/2005 5 13.2 5 66.8 

1/17/2005 5 20.4 5 49.6 
APPENDIX COD, Attachment 5 

4 

Week 

(MM/DD/YYY) 

ArprtR-101 ArprtR-102 

Number of daily values 

in weekly average

Weekly Average 

(mg/L)

Number of daily 

values in weekly 

average

Weekly 

Average 

(mg/L)

1/24/2005 5 19.6 5 91.2 

1/31/2005 5 28.4 5 155.8 

2/7/2005 5 28.2 5 133.6 

2/14/2005 5 34.8 5 168.2 

2/21/2005 5 40.6 5 149.2 

2/28/2005 5 32.4 5 101.6 

3/7/2005 3 29.3 4 89.3 

3/14/2005 3 60.3 3 100.0 

3/21/2005 3 54.3 5 89.4 

3/28/2005 5 39.8 5 92.0 

4/4/2005 5 33.0 5 74.0 

4/11/2005 4 23.3 4 66.3 

4/18/2005 5 28.8 5 73.0 

4/25/2005 5 19.2 5 63.2 

5/2/2005 5 31.0 5 83.4 

5/9/2005 4 17.5 4 79.0 

5/16/2005 2 12.0 2 74.0 

11/28/2005 2 34.5 3 53.3 

12/5/2005 5 67.2 5 122.2 

12/12/2005 3 29.7 5 65.0 

12/19/2005 4 27.0 5 89.4 

1/2/2006 2 29.0 2 145.5 

1/9/2006 1 30.0 1 91.0 

2/6/2006 5 41.4 4 97.0 

2/13/2006 5 41.0 5 99.6 

2/20/2006 5 27.8 5 79.2 

2/27/2006 4 35.5 5 86.8 

3/6/2006 4 32.3 5 81.8 

3/13/2006 5 28.0 5 69.6 

3/20/2006 3 31.0 3 64.0 

3/27/2006 5 20.4 3 66.3 

4/3/2006 5 24.0 5 62.8 

4/10/2006 4 10.3 4 50.8 

4/17/2006 3 48.0 3 42.3 

1/1/2007 5 19.8 3 60.0 

1/8/2007 4 2.8 4 16.5 

4/2/2007 3 29.0 3 61.0 

4/9/2007 1 26.0 1 86.0 

4/16/2007 5 41.4 5 117.6 

4/23/2007 5 21.4 5 106.0 

4/30/2007 5 25.4 5 84.4 

5/7/2007 5 9.2 5 38.8 

5/14/2007 5 6.4 5 25.4 

5/21/2007 5 6.8 5 32.6 
APPENDIX COD, Attachment 5 

5 

Week 

(MM/DD/YYY) 

ArprtR-101 ArprtR-102 

Number of daily values 

in weekly average

Weekly Average 

(mg/L)

Number of daily 

values in weekly 

average

Weekly 

Average 

(mg/L)

5/28/2007 1 136.0 1 90.0 

12/31/2007 2 111.0 0 

1/7/2008 5 312.2 0 

1/14/2008 5 46.4 0 

1/21/2008 5 44.0 0 

1/28/2008 5 41.0 0 

3/3/2008 4 50.3 4 49.8 

3/10/2008 5 54.4 5 43.2 

3/17/2008 5 56.4 5 41.6 

3/24/2008 5 46.8 5 36.8 

3/31/2008 5 41.6 5 32.8 

4/7/2008 5 47.2 5 40.6 

4/14/2008 5 37.6 5 31.2 

4/21/2008 5 47.4 5 34.0 

4/28/2008 5 27.4 5 27.4 

5/5/2008 5 26.6 5 28.8 

5/12/2008 3 40.7 5 37.8 

5/19/2008 5 20.6 5 18.6 

5/26/2008 5 19.6 5 17.0 

6/2/2008 3 38.7 5 36.4 

6/9/2008 1 38.0 1 22.0 

12/8/2008 1 32.0 1 42.0 

12/15/2008 5 33.4 5 31.2 

12/22/2008 5 176.8 5 84.4 

12/29/2008 5 34.2 5 26.6 

1/5/2009 5 30.6 5 28.4 

1/12/2009 5 30.0 5 31.6 

1/19/2009 5 28.8 5 34.2 

1/26/2009 5 47.8 5 34.2 

2/2/2009 5 29.0 5 26.8 

2/9/2009 5 30.6 5 32.0 

2/16/2009 5 39.8 5 44.4 

2/23/2009 5 47.6 5 50.6 

3/2/2009 5 49.0 5 42.0 

3/9/2009 5 39.8 5 47.6 

3/16/2009 5 41.8 5 44.0 

3/23/2009 5 28.6 5 34.6 

3/30/2009 5 29.2 5 40.8 

4/6/2009 5 34.6 5 34.8 

 
APPENDIX COD, Attachment 6 

1 

APPENDIX COD, Attachment 6 

Weekly Averages Greater than the Weekly Average Limitation 

Date 

Unit ArprtR-101 Unit ArprtR-102 

Concentration (mg/L) 

Is Average 

Greater Than 

Limitation? 

Concentration (mg/L) 

Is Average 

Greater Than 

Limitation? 

Week 

(MM/DD/YYY) Day within a 

Week 

Daily 

Value * 

Weekly 

Average 

Daily 

Value 

* 

Weekly 

Average 

3/20/2000 20MAR2000 126 187.5 Yes 2 37.75 No 

21MAR2000 212 30 

22MAR2000 97 26 

23MAR2000 315 93 

2/19/2001 23FEB2001 140 140.0 No 168 168.0 Yes 

3/12/2001 12MAR2001 575 162.4 Yes 92 64.0 No 

13MAR2001 91 52 

14MAR2001 63 75 

15MAR2001 36 40 

16MAR2001 47 61 

3/19/2001 19MAR2001 104 102.0 No 105 165.75 Yes 

21MAR2001 . 105 

22MAR2001 129 393 

23MAR2001 73 60 

5/19/2003 19MAY2003 460 337.0 Yes 95 87.4 No 

20MAY2003 655 86 

21MAY2003 178 83 

22MAY2003 290 101 

23MAY2003 102 72 

1/5/2004 05JAN2004 33 190.8 Yes 35 36.4 No 

06JAN2004 267 40 

07JAN2004 42 38 

08JAN2004 387 37 

09JAN2004 225 32 

3/15/2004 15MAR2004 69 257.4 Yes 100 112.4 No 

16MAR2004 316 124 

17MAR2004 699 118 
APPENDIX COD, Attachment 6 

2 

Date 

Unit ArprtR-101 Unit ArprtR-102 

Concentration (mg/L) 

Is Average 

Greater Than 

Limitation? 

Concentration (mg/L) 

Is Average 

Greater Than 

Limitation? 

Week 

(MM/DD/YYY) Day within a 

Week 

Daily 

Value * 

Weekly 

Average 

Daily 

Value 

* 

Weekly 

Average 

18MAR2004 123 126 

19MAR2004 80 94 

1/3/2005 03JAN2005 2 63.0 No 18 179.2 Yes 

04JAN2005 275 725 

05JAN2005 2 30 

06JAN2005 24 70 

07JAN2005 12 53 

1/31/2005 31JAN2005 20 28.4 No 72 155.8 Yes 

01FEB2005 24 72 

02FEB2005 25 79 

03FEB2005 35 196 

04FEB2005 38 360 

2/14/2005 14FEB2005 40 34.8 No 94 168.2 Yes 

15FEB2005 33 118 

16FEB2005 38 238 

17FEB2005 30 175 

18FEB2005 33 216 

1/7/2008 07JAN2008 28 312.2 Yes No values for 

this week 08JAN2008 18 

09JAN2008 1042 

10JAN2008 433 

11JAN2008 40 

12/22/2008 22DEC2008 32 176.8 Yes 35 84.4 No 

23DEC2008 35 29 

24DEC2008 27 30 

25DEC2008 674 282 

26DEC2008 116 46 

* Daily Values in bold text are greater than the daily maximum limitation. 
APPENDIX AMMONIA 

1 

APPENDIX AMMONIA 

1 INTRODUCTION 

Based upon its past experience with effluent data, EPA considers the lognormal distribution to be 

appropriate for statistically modeling daily values of ammonia as nitrogen (“ammonia”) 

measurements to obtain the daily maximum limitation. This appendix describes EPA’s use of the 

lognormal distribution in estimating a long-term average and variability factor for the data described 

in Section 14 of the Technical Development Document. Although EPA is not establishing them, this 

appendix also presents equations used to calculate values of the weekly average and monthly average 

limitations. 

EPA calculates effluent limitations using statistical procedures that involve fitting effluent data to 

statistical distribution models and estimating specified upper percentiles of these fitted 

distributions. These percentiles are as follows: 

 A daily maximum limitation is an estimate of the 99

th

 percentile of the distribution of the 

daily measurements. 

 A weekly average limitation is an estimate of the 97

th

 percentile of the distribution of the 

weekly averages of the daily measurements. 

 A monthly average limitation is an estimate of the 95

th

 percentile of the distribution of the 

monthly averages of the daily measurements 

The following sections describe the lognormal distribution and parameter estimates (Section 2); 

adjustments for autocorrelation (Section 3); calculation of the long-term average and daily 

maximum limitation (Section 4); calculation of the weekly and monthly average limitations 

(Section 5); and references (Section 6). 

2 OVERVIEW OF THE LOGNORMAL DISTRIBUTION 

The lognormal distribution is the most commonly used probability density model for environmental 

contaminant data (Gilbert, 1987). EPA’s experience has shown that the daily pollutant concentrations 

in effluent can be modeled by a lognormal distribution for a wide range of industrial categories and 

pollutants. For example, histograms of daily pollutant concentration data associated with effluent 

discharges frequently exhibit positive skewness (i.e., most values tending to occur at the lower limit 

of the data range) and long “tails” to the right (i.e., gradually fewer values at the higher end). Such 

histograms resemble the shape of the probability curve of a lognormal distribution. Scientists have 

used the lognormal distribution to model environmental data, including effluent data, primarily 

because it consistently provides a reasonably good fit to these data. 

The following figure presents an example of a lognormal probability curve. Lognormal 

distributions assign positive probability only to positive values, and pollutant concentrations 

cannot hold negative values. 
APPENDIX AMMONIA 

2 

If a random variable X has a lognormal distribution, then its logarithm Y = log(X) has a normal 

distribution. The lognormal distribution and its properties and common applications are detailed in 

Aitchison and Brown (1969) and in Crow and Shimizu (1988). If Y has a normal distribution with 

expected value μ and variance 

2

, then the cumulative probability distribution function of X (i.e., the 

probability that X can hold values less than or equal to some specified value x) takes the following 

form: 

The expected value and variance of X are as follows: 

where “exp” denotes exponentiation. 

Estimators for the unknown parameters  and 2  of a lognormal distribution are directly related to 

estimators for the expected value and variance of a normal distribution. Let {x1, ..., xn} represent a 

set of n sample pollutant measurements, and assume that they represent a random sample from a 

common lognormal distribution associated with the random variable X. Then estimators for  and 

2  are as follows: 

1

1 ˆ log( )

n

i

i

x

n

 

  

Because Y = log(X) has a normal distribution, is known as a maximum likelihood estimator for  , which has 

several highly attractive statistical properties. Also, the estimator 2 ˆ is the maximum likelihood estimator for 2  , 

after an adjustment is made to allow the estimator to be unbiased. 

ˆ

e dt

t

P X x t

x

(log( ) ) 2 /2 2

2

1

[ ]  

 

 



  

X  E[ X]  exp(   0.52 )

 2  Var[ X]  exp( 2  2 )(exp(  2 ) 1) X



  

n

i

i x

n 1

2 2 (log( ) ˆ) 1

1

ˆ 
APPENDIX AMMONIA 

3 

3 AUTOCORRELATION

Effluent data from wastewater treatment technologies may be autocorrelated which can lead to a bias 

in the variance estimation, if not adjusted appropriately. For example, autocorrelation would be 

present in the data if the loading of a pollutant is relatively high one day, and is likely to remain high 

the next, and possibly, succeeding days. The measurements may be similar from one day to the next 

because of retention of wastewater in basins, holding ponds, and other components of the wastewater 

system. For data with autocorrelation, statistical time series are appropriate for modeling the data. 

There are many time series models that might be considered for modeling wastewater 

measurements. One method of modeling autocorrelation is by using an autoregressive lag-1 model, 

designated as an AR(1) model. The AR(1) model is a reasonable model for many series of 

wastewater measurements. The AR(1) model has one parameter, ρ1

, the correlation between 

the measurements from successive sampling events, of which time intervals are equally spaced, 

otherwise referred to as the lag-1 correlation. 

4 CALCULATION OF LONG-TERM AVERAGE AND DAILY MAXIMUM 

LIMITATION 

In calculating the long-term average and daily maximum limitation, the autocorrelation affects the 

variance estimates for the data and is adjusted as shown in the following equation: 

For an AR(1) model with 1-day lag correlation of ρ1and n sequential daily values (T = {1..n}),

Corr(ln(xi

), ln(xj)) = 1

i j   . The adjustment for the autocorrelation is: 

1

() 1 ( 1)

i j

iT jT

j k g R

n n

 

    



where T is the set of days with observed daily values. For an AR(1) model with n sequential daily 

values, this reduces to: 

1

1 11

1

1 1

(1 ) 2 ( 1) 1 1

n i j

iT jT

j k

n   

 

 

 

              



















   















 















  



1

1

1 1

1

1

1

(1 ) ( 1) ( 1) 1

2 ( ) 1



 



 n

n

n n

g R

where ρ1 is the correlation of the natural logarithm of measurements from successive sampling 

events. Note that if the daily values are independent (autocorrelation is not present in the data), g(R) 

= 1. However, as explained in Chapter 14 of the Technical Development Document, EPA set the 



  

n

i

A i x

g R n 1

2 2 (log( ) ˆ) ( )( 1)

1

ˆ 
APPENDIX AMMONIA 

4 

value of ρ1 equal to 0.61291. 

The adjusted variance estimate is then used to calculate the long-term average and 99

th

 percentile 

(used as the basis of the daily maximum limitation) as follows: 

Long - Term Average = LTA = exp( ˆ 0.5 ˆ ) 2    A

Daily Maximum Limitation = 99 Pˆ = exp( ˆ 2.32 ˆ )    A

where the value of 2.326 is the 99

th

 percentile of the standard normal distribution (i.e., the normal 

distribution with μ=0 and 2  =1, whose cumulative distribution function is often denoted by (x)). 

The daily variability factor can be calculated as the ratio of the daily maximum limitation to the 

long-term average: 

Daily Variability Factor = 99 Pˆ

LTA

5 CALCULATION OF WEEKLY AND MONTHLY AVERAGE LIMITATION 

This section describes the derivation of the weekly and monthly limitation, even though 

EPA does not establish weekly or monthly limitations for ammonia. 

In its derivation of the value of the weekly average limitation, EPA used an estimate of the 97

th

percentile of the weekly averages of the daily measurements. The variance also was adjusted in 

modeling the averages of daily values for the weekly average limitation and monthly average 

limitation, but in a slightly different manner. In general, the fm factor to adjust for autocorrelation can 

be written as: 

2

2

1 exp( ) 1 ˆ ( ) exp( ) 1 ˆ

i j

A

m

iSjS A

j i

f

m

  





 

   

where S is the set of days (represented by sequential numbers) on which samples for the average are 

taken and m is the number of days in S. 

The weekly average limitation can then be calculated as the product of the long-term average 

(LTA, as shown above) and weekly variability factor (VF5) as follows: 

Weekly Average Limitation = LTAxVF5
APPENDIX AMMONIA 

5 

exp(1.881 ˆ 0.5 ˆ ) [ ] ˆ

ˆ 2

5 5

5

97

5     

E U

P

VF

with Ū5 indicating the (statistical) expected value of the average of the five daily values. The variance is estimated 

as: 

2 2

5 51

1 ˆ ˆ log(1 (exp( ) 1)(1 ( ))) ˆ 5 A      f

1

2 4

5 1 2

1

2 exp( ) 1 ˆ ( ) (5 ) 5 exp( ) 1 ˆ

i

A

i A

f i  

  

    

The monthly average limitation can be calculated as the product of the long-term average (LTA) 

and weekly variability factor (VF20), as follows: 

Monthly Average Limitation = LTAxVF20 

where 

VF20 = 1 + 1.645 2

20

ˆ (exp( ) 1)(1 ( )) / 20 ˆ ˆ A     f

For a monthly average based on 20 samples collected on weekdays, S is a set of 20 numbers starting 

from 1 representing the days on which samples are taken. The value of f20 depends on which day, 

Monday through Friday, is assumed to be the first day of the month. The calculations assume that 

the first day of the month is Monday, in which case S is the set of numbers: 1,2,3,4,5, 8,9,10,11,12, 

15,16,17,18,19, 22,23,24,25,26. The resulting formula cannot be easily simplified. The assumption 

that Monday is the first sampling day results in the largest possible values for f20. Thus the formula 

for f20 is: 

2

20 2

1 exp( ) 1 ˆ ( ) 20 exp( ) 1 ˆ

i j

A

iSjS A

j i

f   





 

   

6 REFERENCES 

Aitchison, J, and Brown, JAC. (1969) The Lognormal Distribution. Cambridge: Cambridge 

University Press. 

Crow, EL, and Shimizu, K. (1988) Lognormal Distributions: Theory and Applications. New 

York: Marcel Dekker, Inc. 

Gilbert, RO (1987) Statistical Methods for Environmental Pollution Monitoring. New York: Van 

Nostrand Reinhold Company, Inc.