United States
Environmental Protection
Agency
Office of
Solid Waste and
Emergency Response
Publication 9200.5-160FS
PB95-963501
EPA 540/F94/059
July 1994
The Penta Wood Products Site:
Analysis of Pentachlorophenol Using A
Mobile Laboratory Equipped With
State-of-the-Art Instrumentation
Office of Emergency and Remedial Response
Emergency Response Division
Environmental Response Branch MS-101
Introduction
The Penta Wood Products Site is an inactive wood treating
facility located in Siren, Wisconsin. The site covers an
area of 120 acres, 80 of which were actively used. The fa-
cility operated from 1953 until 1992, when it was forced
to close because of its inability to comply with the Re-
source Conservation and Recovery Act (RCRA) of 1976
drip track regulations.
From 1956 to 1975, pentachlorophenol (PCP) was used to
chemically treat wood products. After 1975, ammoniacal-
copper-arsenate (ACA) was in use. PCP was also com-
bined with No. 2 fuel oil to create a five to seven percent
solution, which was stored in vats for a wood pressure
treatment process. The process involved submerging white
wood products in the solution.
The United States Environmental Protection Agency's En-
vironmental Response Team (U.S. EPA/ERT) examined
the site to determine the extent and degree of contamina-
tion and to assess the ecological and human health con-
cerns. Because of the size of the site and the hazardous
nature of the pollutants (possible dioxin contamination),
the U.S. EPA/ERT's High Hazard Mobile Laboratory, lo-
cated in Brunswick, Georgia was activated to support the
remediation of the site. This field laboratory is equipped
with the capability to analyze a high volume of dioxin
contaminated samples for creosote/PCP and provide ana-
lytical results within 24 hours, which allows quick deci-
sion making at a site.
The majority of the samples taken were soil, which was
classified as either surficial or subsurface. Over a four-
week period, 685 samples were collected for PCP analysis.
Two Gas Chromatography/Mass Spectrometry (GC/MS)
chemists were sent to Brunswick, Georgia on April 6,
1994, and completed the entire extraction and instrumental
analyses by May 6, 1994. During that time, the tabulated
PCP results were transmitted to the site task leader on a
daily basis.
Quick Reference Fact Sheet
U.S. EPA/ERT Field Analytical
Methods for PCP
The use of GC/MS provides good overall sensitivity and
positive identification for specific compounds such as
PCP. Field GC/MS methods developed by the U.S.
EPA/ERT, in conjunction with the Response Engineering
Analytical Contract (REAC), provide rapid turnaround of
sample results while incorporating rigorous Quality Assur-
ance/Quality Control (QA/QC) procedures to ensure reli-
ability of the analytical data.
When combined with a quick, efficient extraction proce-
dure, the analytical method provided by the mobile lab al-
lows for the timely and successful completion of any site
investigations requiring on-site analytical support. For the
Penta Wood Products investigations, the GC/MS analyti-
cal method incorporated three key factors:
• Selected Ion Monitoring (SIM) for achieving high
sensitivity and a low method detection limit, allowing
for minimum sample amount and solvent volume to
be used.
• A GC oven temperature program designed to analyze
a sample extract every 15 minutes.
• A capillary column capable of adequately resolving
the compounds of interest under rapid temperature
ramping. The end result of the analytical method is
the processing of 96 sample extracts every 24-hour
period, while still meeting the prescribed QA/QC cri-
teria.
Of equal importance, and in addition to the analytical
method, an extraction procedure was developed to handle
the large numbers of samples received by the mobile labo-
ratory on a daily basis. Conventional soil extraction proce-
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dures such as sonication or Soxhlet extraction would not
be practical for a field mobile laboratory.
Ten grams of sample were extracted in sealed 100 millili-
ters (ml) serum vessels. The soil samples and blanks were
spiked with 500 microliters (|il) of 1000 jig/ml 2,4,6-tri-
bromophenol surrogate solution and mixed with anhy-
drous sodium sulfate. The samples were then extracted
with 100 rnl acetone/methylene chloride mixture. With
two shaker tables operating simultaneously, this procedure
easily enabled the laboratory personnel to extract 50 sam-
ples per day.
Field Analytical QA/QC Criteria
and Performance
A GC/MS HP 5971A system, equipped with a quadrupole
mass spectrometer and a DOS/CHEM station, was oper-
ated in SIM mode. The standard concentrations ranged
from a low of 0.5 Hg/ml (ppm) to a high standard concen-
tration of 50 ng/ml. The percent relative standard devia-
tions (RSD) achieved for a six-point range was always
within the 30 percent limits indicating the linearity of
PCP. The 0.5 standard enabled the lab to report a 5 mg/kg
detection limit on a wet weight basis for soil samples. Val-
ues for sample results were reported at or above 0.1 Hg/ml
in the sample extract. On a daily basis, a 50 (ig/ml de-
cafluorotriphenylphosphine (DFTPP) tune standard was
analyzed to pass the U.S. EPA Contract Laboratory Pro-
gram (CLP SOW OLMO1.0 3/90) tune criteria, and a 5.0
ppm daily check standard was analyzed to compare with
the average response factors from the calibration range. A
±25 percent difference for daily check response factors
was the expected criteria for daily sample analyses to con-
tinue.
The CLP recovery limits were used as a guideline during
the entire analysis. Since the mobile GC/MS field labora-
tory is using modified methods, the surrogate and Metric
Spike/Metric Spike Duplicate (MS/MSD) recoveries were
compiled in order to monitor the laboratory data quality.
Statistical data was gathered from 782 sample analyses
and 37 pairs of matrix spike analyses to generate the ac-
ceptable recovery ranges for this particular method. Using
a 95 percent confidence interval, the recovery ranges for
the surrogate, 2,4,6-tribromophenol are between 44 and
126 and the ranges for the matrix spike compound PCP
are between 75 and 144. These criteria reflect the normal
expected ranges for these two compounds analyzed at the
GC/MS mobile laboratory, using the previously described
analytical and extraction methods.
Conclusions
Utilization of field-modified GC/MS methods has proven
to be an effective approach to meet contaminant analysis
needs at wood treating hazardous waste sites, such as
Penta Wood Products. High-quality results are achieved
quickly. Providing results within 24 hours of sample re-
ceipt allows the Site Project Managers to quickly make de-
cisions in the field and to effectively conduct any required
changes in clean-up operations, hese analytical results
from the mobile field laboratory are the results of proven
field methodologies incorporating rigorous QA/QC proce-
dures,
On-going operations at the high hazard mobile field labo-
ratory continue to provide fast, cost-effective analysis of
PCP and other organic analytes. By analyzing samples
from the Penta Wood Products Site at the field laboratory
instead of at an in-house contracted lab, approximately
$200,000 was saved. The mobile field laboratory has
proven to be an ideal concept for characterization and re-
mediation/removal activities at many hazardous waste
sites.
For further information,
please contact: Raj Singhvi (908) 321-6761
(908) 321-6660 (24-hour hotline)
U.S. EPA/ERT
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