p. 1 of 5 

From: Putney, David 

Sent: Monday, August 19, 2013 10:56 AM 

To: 'Backfisch Don (NORALNM)' 

Subject: RE: Noranda 

Don, 

Thanks so much for this information. I’ll let you know if I have any more (last, hopefully) questions on the 

report once I get a chance to discuss these responses with our testing folks. 

Thanks again, 

David Putney, Environmental Engineer 

U.S. Environmental Protection Agency 

Office of Air Quality Planning and Standards 

Sector Policies and Programs Division 

109 T.W. Alexander Drive, RTP, NC 27711 

Mail Drop D243-02 

Ph: (919) 541-2016 Fax: (919) 541-3207 

Email: putney.david@epa.gov

From: Backfisch Don (NORALNM) [mailto:Don.Backfisch@noralinc.com] 

Sent: Monday, August 19, 2013 8:49 AM 

To: Putney, David 

Subject: FW: Noranda 

Below is the explanation we got from the lab (in red) concerning your questions. I apologize for not 

getting these to you sooner. Let me know if you have other questions and I’ll try to get them 

answered as quickly as I can. 

Don Backfisch 

From: Scott Brown [mailto:sbrown@cleanair.com] 

Sent: Tuesday, August 06, 2013 8:54 AM 

To: Backfisch Don (NORALNM) 

Subject: FW: Noranda 

Don, See the lab responses below.

Scott B.

From: Ron McLeod [mailto:Ron.McLeod@alsglobal.com] 

Sent: Tuesday, August 06, 2013 8:50 AM 

To: Scott Brown 

Subject: RE: Noranda

 

Below in red type are my respective responses to the Noranda enquiries below.

Regards
p. 2 of 5 

Ron

Ron McLeod Ph.D.

Director, Air Toxics and Special Chemistries, Eastern Canada

ALS Life Sciences Division | Environmental

5420 Mainway Drive #5

Burlington, ON Canada, L7L 6A4

T +1 905-331-3111 ext. 222

M +1 905-516-2687

F +1 905-331-4567

www.alsglobal.com

From: Scott Brown [mailto:sbrown@cleanair.com] 

Sent: Wednesday, July 31, 2013 2:22 PM 

To: Ron McLeod 

Subject: Noranda

 

Ron, This was sent to Don and Nancy at Noranda. Please respond with whatever enlightenment you can. 

 

Nancy, 

 

I have done a quick review of the ICR data submitted for the Noranda primary aluminum facility in New 

Madrid, MO, and have a few comments and questions for you and the testing/lab contractors. Note that in the 

discussions below, unless otherwise specified, please refer to page G-124 of the lab data (see page 626 of 748 

in the pdf Final Report) when discussing dioxin/furan (D/F) data and refer to page G-165 of the lab data (see 

page 667 of 748 in the pdf Final Report) when discussing polychlorinated biphenyl (PCB) data as “typical” 

examples. These data are for run 1 on the paste plant. 

 

• Some of the target analytes are flagged with an “R” which, according to the footnotes in the lab 

report, indicates that the ion abundance ratio for the compound in question did not meet the 

acceptance criterion. These flags occur in both the PCB and D/F analyses, but are more common in the 

D/F analyses. I need assistance in interpreting the concentration values associated with the analytes 

flagged with an R. How were data flagged with an R handled by the lab? How was the data used in 

interpreting the analyte concentrations? (i.e. What value was used when calculating concentrations?)

One of the method requirements for positive peak identification is that the observed ion abundance ratio of 

the two monitored chlorine isotope m/z responses needs to be within 15% of the theoretical ratio. If a peak 

fails this criterion, then it cannot be identified as a real PCDD/F or PCB congener. However, the presence of a 

peak at the right retention time can mask the presence of a real peak. Therefore we quantify this value based 

upon the instrument response to the lower of the two monitored masses and report this value with a ‘<’ in 

front of the value to represent the maximum possible level. Then this <value is flagged with the ‘R’

flag. Note that by standard protocols we are to quantify down to 2.5:1 signal to noise. As you can imagine, 

as one approaches 2.5:1 signal to noise (presented as the EDL), that there is significant random noise

contribution to each peak response. Therefore, as one approaches the EDL, the frequency of ‘R’ flagged data 

increases. These data points may represent real PCDD/F or PCB values, but have failed the tight +/-15% ion 

abundance ratio criterion. In our judgment and according to the method, ‘R’ flagged data are not confirmed 
p. 3 of 5 

peaks of PCDD/F or PCB. However, for the calculation of upper bound TEQs, we include the full maximum 

possible concentration for that peak in the corresponding calculations. For lower bound TEQ values, we take 

the ‘R’ flagged results as zero.

CARB 428 Section 6.7.4 (reproduced below for convenience) requires calculating the EMPC when the 

quantitation ion is determined to be greater than the EDL but the ion abundance ratio criteria is not met. It 

appears that the lab used the secondary ion to report the results instead of the quantitation ion. However, 

there does appear to be some confusion on this point, as the lab states the value is based on the “lower of the 

two monitored masses” but that it represents the “maximum possible level”. Please confirm or clarify our 

interpretation that your calculation procedure uses the standard calculation to quantitate target compounds 

for the “upper” bound TEQ and flags these data as EMPC if appropriate. Please also confirm or clarify our 

interpretation that your calculation procedure uses the smaller of the characteristic compound ions to

quantitate target compounds for the “Lower” bound TEQ. The EMPC would be the maximum possible level, 

which is the value using the method required quantitation ion, not the secondary ion. Please confirm which 

value reported with the less than sign is the EMPC.

Additionally, if the results provided are not the EMPC values, we would like these values to be provided, or if 

they are provided already, please identify your variable name and where this value is found in your report. 

6.7.4 Estimated Maximum Possible Concentration 

If the response of the quantitation ions is determined to be greater than 2.5 times the background signal, but 

qualitative identification criteria are not met, an “estimated maximum possible concentration” must be

calculated according to Equations 428-7 and 428-8.

• I need help interpreting the concentration values associated with the analytes that are flagged 

with a “J” (which, according to the footnotes in the lab report, indicates that the analyte was detected 

below the calibrated range) but which have listed concentrations well above the listed EDL. For 

example, for Total MonoCB – which is flagged with a J on page G-165 of the final report - the EDL is 

listed as 24 picograms (pg) whereas the listed concentration is 2400 pg.

‘J’ flag generally refers to estimated value and below the instrument calibration range. The flag and basic 

interpretations are derived from the US EPA CLP analytical program. Below is the actual wording from the 

PCB CLP document CBC01.2, the CLP version of 1668A. Note that the CRQL is at the concentration equivalent 

to the level in the low calibration standard.

“J - Indicates an estimated value. This flag is used when the mass

spectral data indicate the presence of an analyte meeting all the

identification criteria in Exhibit D, but the result is less than

the Contract Required Quantitation Limit (CRQL), as listed in

Exhibit C, but greater than the calculated Estimated Detection

Limit (EDL).”

Although not specifically defined in CBC01.2, by some interpretations, any homologue group total values are ‘J’ 

flagged. Perhaps this is due to the summation of peak responses in which some or many are below the level 

of the low calibration standard.

• The concentration values associated with the analytes that are flagged with both “J” and “R” are 

listed in the spreadsheets as below detection limit (BDL). See for example OCDD (flagged with J and R
p. 4 of 5 

in the lab report and listed as BDL in the D/F portion of the associated Excel spreadsheet PrAl_ICR_ 

PastePlant.xls). Why are these data marked as BDL when they were analyzed above the MDL? Data 

that is flagged with only a J is not marked as BDL. This is what we would expect; we would expect only 

U flagged data to be marked BDL.

BDL should be a flag on ‘R’ flagged data but not ‘J’ flagged data. ‘J’ flagged data should be ADL. You are 

correct that U flagged data should be BDL.

Why are the R flagged data marked at BDL? Doing so assumes that any time the quality assurance indicators 

of the method are not met that the compound is not detected, when there is no indication that this 

assumption is accurate. Many R flags occur with a J flag, indicating that R flagged data may very well have 

been detected. If data is both R and J flagged – how can data be both BDL and ADL? 

• The material throughput rates listed in the Final Report do not always agree with those listed in 

the summary spreadsheets. For example, Tables 2-13, 2-19, 2-23, and 2-28 list throughput rates of 

10.33 tons per hour for potline 2, 6.30 tons per hour for potline 3 (listed as 161 duct), 7.79 tons per 

hour for carbon bake, and 33.7 for paste plant, respectively. However, the PCB summary spreadsheet 

for potline 3 (again, listed as 161 duct) lists a throughput of 7.79 tons per hour. Please confirm the

material throughput rates for the tested potlines, the carbon bake furnace and the paste plant during 

the testing.

For Scott Brown:

• The carbon bake furnace and the paste plant summary spreadsheets indicate throughput 

materials of aluminum as opposed to the expected material of green anode. Please confirm the 

throughput materials for the carbon bake furnace and the paste plant and whether the pounds per ton 

emissions rates cited in these spreadsheets are in units of pounds of pollutant per ton of aluminum 

produced or pounds of pollutant per ton of green anode processed.

For Scott Brown

• Specifically regarding the PCB analyses - I notice that although the lab reports cite values of PCB 

in units of pg, those values were listed in the associated summary spreadsheets in units of nanograms 

(ng). That is, for example, the lab results indicate 2,400 pg of total monochlorinated 

biphenyls whereas the PCB portion of the associated spreadsheet (PrAl_ICR_PastePlant.xls) indicates 

2,400 ng of total monochlorinated biphenyls. This would appear to have caused an overestimation of 

PCB emissions from your facility by a factor of 1,000. Please confirm or modify, as appropriate, the PCB 

emissions values cited in the summary spreadsheets.

For Scott Brown’s input. We reported in pg. 

• Specifically regarding the PCB analyses - I notice that for the homologue group totals the EDL is 

sometimes lower than the cited concentration for those homologue groups flagged with a U. For 

example, for the Total OctaCB homologue group (which is flagged as U) the lab report cites a 

concentration of <23 pg (which would suggest a method detection limit of 23 pg) but an EDL of 9.1 pg. 

Please clarify how the EDL is less than the method detection limit for these groups.

The EDL value by each total homologue group total is from a general signal:noise measurement for the each 

homologue group total region. However there are many peaks for each homologue group totals. For 

example for octachlorobiphenyl, there are 12 congeners (11 peaks, one co-elution). Each peak has it’s own 

EDL determined. The <23 value is the highest EDL among the individual octa- peaks. 
p. 5 of 5 

Please provide the D/F and PCB MDLs per page 3 of Attachment 1 of the ICR. (Note that the ICR 

specified that you must use the MDL determination procedure in EPA Method 301, Section 15 to 

develop the MDL and further specified that the MDL must be determined in the same matrix as the 

samples that will be analyzed.) 

Please provide your definition of, and your current values for, Level of Detection (LODs) and Level of

Quantitation LOQs for D/F and PCBs. Please clarify why you flag some data that is well above the EDL 

as “J” (For example (see page 610 of 748 in the pdf version of the report), OCDD is reported at more 

than 18 times EDL but is still J flagged.) 

Additionally, in the lab report (for example, see page 610 of 748 in the pdf version of the report) we

need an explanation on why there are two runs on the samples. Did these compounds fail to meet 

quality specifications in the first analysis, requiring dilution or reprocessing archived samples to 

determine the concentration? Or does your procedure perhaps use different GC columns to resolve 

particular congeners? 

• Specifically regarding the D/F analyses - When the cited mass for a total homologue group is 

preceded by a “<” symbol does this indicate below detection limits? I ask because the lab report does 

not provide a “U” flag for these homologue groups.

Yes it identifies the values as non-detected at the listed value.

 

Note that my contractor and I have not finished reviewing the report yet, and we may have other questions in 

the future. We are trying to resolve questions as we find them instead of holding them until the end.

 

Thanks, 

 

David Putney, Environmental Engineer 

U.S. Environmental Protection Agency 

Office of Air Quality Planning and Standards 

Sector Policies and Programs Division 

109 T.W. Alexander Drive, RTP, NC 27711 

Mail Drop D243-02 

Ph: (919) 541-2016 Fax: (919) 541-3207 

Email: putney.david@epa.gov

 

 

Regards,

Scott Brown

Senior Project Manager

CleanAir

847-654-4544 (office)

847-612-0561 (cell)