Document ID: EPA-HQ-OPP-2006-0693-0028
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2006-10-20T04:00Z

ARCADIS G&M, Inc.

4915 Prospectus Drive

Suite F

Durham

North Carolina 27713

Tel 919 544 4535

Fax 919 544 5690

MEMO

To:

Victor D’Amato	Copies:

Copies

From:

	Kim Egler

	Date:	ARCADIS Project No.:

25 November 2003	RN992015.0013.00001

Subject:

	Validation of Wipe Samples from CCA Treated Wood Collected June 17 and
July 1, 2, and 8, 2003



One-hundred and eight (108) samples were collected on June 17 and July
1, 2 and 8, 2003 from the CAA Treated Wood Minidecks located at the
USEPA in Research Triangle Park, North Carolina.  These samples were
triple-extracted with 10 percent nitric acid by ARCADIS personnel and
submitted by overnight courier at ambient temperature on July 28, 2003
to STL Savannah, Savannah, Georgia.  Samples were analyzed on August 6,
12, and 13, 2003.  This validation covers the samples submitted for
arsenic (As), chromium (Cr), and copper (Cu) analysis by USEPA Method
200.8 (ICP-MS, modified).  This methodology was modified to utilize
hydrogen plasma, rather than argon, as classically performed.  This
modification eliminates concerns over the formation of Ar40Cl35, which
can create a positive bias when measuring As.

Sample Delivery Group (SDG) WIPE01, Project Number S385875A

SS-147 through SS-163

SS-167 through SS-176

SS-194 through SS-256

SS-263 through SS-278

SS-290 through SS-291

Validation of this data was performed following the quality
assurance/quality control (QA/QC) criteria set forth in the “USEPA
Contract Laboratory Program (CLP) National Functional Guidelines (NFG)
for Inorganic Data Review,” July 2002.  The NFG have slightly
different criteria for some parameters than does Method 200.8.  In these
cases, the more stringent criteria were used.

Metals Inorganic Review

I.	Preservation and Holding Times

The samples arrived at the laboratory promptly and were analyzed within
the analytical holding time.  The samples had been shipped at ambient
temperature after being triple-extracted in 10 percent nitric acid. 
Although the NFG recommends maintaining aqueous samples at 4ºC±2ºC,
no action is specified for this condition, and no action was taken.  The
Case Narrative included sample identifications and indicated that all
samples were analyzed at various dilutions for As, Cr, and Cu, due to
the abundance of these metals. 

II.	ICP-MS Tune Analysis

As required, 100 ug/L (ppb) tune checks were run on the required
isotopes before each calibration.  Each tune was run five times in a
row, exceeding the four times in a row criteria required by the method. 
The percent Relative Standard Deviation (%RSD) was less than 5% for all
isotopes, and the mass calibrations and peak widths met control
criteria.

III.	Calibration

The instrument was successfully calibrated each of the three days that
samples were analyzed.  The four-point calibration range was from 0.5 to
100 ug/L.  It should be noted that the calibration for the samples
analyzed on August 6, 2003 was performed late in the evening on August
5, 2003.  

Initial Calibration Verification (ICV) samples were run immediately
following each calibration, and all three metal recoveries fell within
the 90-110% control limits.  Continuing Calibration Verification (CCV)
samples were run at a frequency of 10 percent, and at the beginning of
the run and after the last sample, as required.  All recoveries were
within established control limits.

The Contract Required Quantitation Limit (CRQL) sample, referred to as
the CRDL in the lab report, was run as the first sample in the run,
immediately preceding the Interference Check Samples (ICS), as
stipulated in the NFG.  Although the NFG states that the CRQL should be
run at the beginning and end of each sample analysis run and every 20
analytical samples, the method has no such requirement.  The CRDL run on
August 6 and August 13, 2003 has recoveries above the control limit for
Cr and Cu, and Cu, respectively.  However, the NFG states that only
results above the Method Detection Limit (MDL) but less than two times
the CRQL are qualified.  All of the associated sample results for these
two metals were more than twice the CRQL, and no action was taken.  The
CRDL run on August 12, 2003 had a recovery above 180% for Cu.  The NFG
recommend all results above the MDL be qualified as unusable “R.” 
However, the CRDL was run at 0.1 ug/l, whereas all of the associated
sample results are far higher, exceeding 1,000 ug/L.  Given the
difference in magnitudes, and the fact that all of the ICVs and CCVs had
acceptable recoveries, no action was taken.      

IV.	Blanks

An Initial Calibration Blank (ICB) was run following each ICV, and was
nondetect for any of the target metals.  Continuing Calibration Blanks
(CCB) were run immediately following each CCV at a frequency of 10
percent, as well as at the beginning of the run and after the last CCV. 
All of the CCBs were nondetect for the three metals.  Because the
samples were extracted prior to shipping to the laboratory, there were
no Preparation (Method) Blanks associated with these samples, and the
CCBs were used as the Method Blanks.  No blind field blanks or field
blanks (extraction fluid only) were included in this SDG.    

V.	Inductively Coupled Plasma-Interference Check Sample (ICS)

Interference Check Samples (ICS) were run at the beginning of each of
the three runs, after the ICV, and were followed by a CCV and CCB, as
required.  The recoveries fell within the control limits and gave no
indication of isobaric interferences.  

VI.	Laboratory Control Sample (LCS)

Because the laboratory did not extract the samples, the CCVs were used
as the LCS samples.

VII.	Duplicate Sample Analysis

Duplicate samples – like LCS samples – are to be carried through the
entire preparation and analysis process. Because the laboratory did not
extract the samples, no duplicate analyses were performed.

VIII.	Spike Sample Analysis

Because the laboratory did not extract the samples, Matrix Spike (MS)/MS
Duplicate (MSD) samples could not be analyzed.  Therefore, Post
Digestion Spike (PDS) samples were run at a frequency of 10 percent. 
All recoveries were within control limits.  No spiked samples were
submitted with this SDG.

IX.	ICP Serial Dilution

Five serial dilutions were performed on samples from this SDG.  Four of
the samples had recoveries within the 10 percent acceptance criteria. 
The remaining sample, SS-149L, had recoveries above 10 percent for all
three metals, and had sample results for each metal that were more than
50 times the MDL.  Because the other serial dilution samples showed no
indication of significant physical or chemical interferences due to
sample matrix, only the results for sample SS-149 were qualified as
estimated “J.”  

X.	ICP-MS Internal Standards

All of the Internal Standard recoveries were within control limits.

XI.	Field Duplicates

There were no Field Duplicates included in this SDG.

XIII.	Overall Assessment

The reported data meets the acceptance criteria established in the NFG
and associated methods and plans.  Data quality is sufficient for its
intended use.

 

 

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