Rochelle: 

My responses (please share as broadly as needed): 

You may use SW 846 Method 6010C in lieu of Method 6020A for Hg analyses
with the caveat that if the lab finds values less than the IDL
documented for in accordance with the method, we would expect a
re-analysis with Method 6020A. 

For the determining the Cr6 content, we recommend ASTM D5451-93(2008)
the dust sampling, we recommend SW 846 Method 3060A and to Method 7195
or 7197 for analysis.  You may report data analyzed with Method 7196 if
you find levels above the test specific method detection level.  If
not, you should use one of the more sensitive methods.  Instead of
specifying a minimum expected  method level, we refer to specific
analytical methods, in this case, Method 7195 or Method 7197.  Please
report data in terms of the method detection level (e.g., below
detection level, BDL)  and not the method reporting limit.  

Peter Westlin

Measurement Policy Group

OAQPS, SPPD

919-541-1058

----- Forwarded by Rochelle Boyd/RTP/USEPA/US on 07/12/2010 07:45 AM
----- 

Dear Ms. Boyd: 

We have been asked to provide analytical support in the way of sample
analysis and data report preparation in response to the “Information
Collection Request for the Secondary Aluminum Production Source
Category”.

On review of the May 27, 2010 information request letter and the
Enclosure 1, I have a few questions that need your clarification
pertaining to the baghouse dust analysis portion of this request: 

1.       Do you have an Excel report format for the baghouse dust
data? 

2.       In Table 2.2  a) is EPA Method 6020 (ICP/MS) the only
method allowed for Hg analysis?  While Hg can be analyzed by ICP/MS it
is not the generally preferred method.

b) Is the sample preparation method EPA Method 3051 (Microwave
Digestion) the only sample preparation method allowed or would other
sample preparation methods be permitted (for example those that use a
Parr bomb) or other digestion techniques? 

3.  Concerning Hexavalent Cr analysis is EPA Method 218.6 the only
acceptable method for this analysis?  I have concerns that the method
has been developed for aqueous matrices and that chlorides and 

    other metals species can cause analytical problems for this ion
chromatographic method.   What is the desired Reporting Limit in the
solid material? 

Your prompt assistance with these questions would be appreciated.  If
you need to discuss them further I will be available either by phone or
by email at the address below. 

Thank you, 

Rick Moore 

President 

American Analytical Laboratories, Inc. 

840 South Main Street 

Akron OH 44311 

  HYPERLINK "mailto:rmoore@aal-inc.com"  rmoore@aal-inc.com 

ph: 330-535-1300 

fax: 330-535-7246 

