Let's Take A Peek at
PEAC-WMD v.5 - by
S. Bruce King
History of AristaTek - Part I
Frequently the AristaTek staff is
asked about our background and past experience. There is a description or history
of the companys past experience posted on our web site (http://www.aristatek.com/history.aspx),
but I felt it might be beneficial and informative to the readers of the newsletter
to fill in that history with some additional details. In addition, I wanted to provide
some insight into the owners background and past experience so the readers can understand
why our perspective of hazardous materials might be different than other developers
of software applications or even the readers perspective.
The inventors of PEAC-WMD program,
as founders of AristaTek, have hands-on experience with all types of hazardous materials!
This is illustrated by the following history of some of that experience developing
real-data under real conditions in the field. This is why the PEAC-WMD tools have
the most accurate and calibrated databases extant. The PEAC-WMD system is more accurate
than other systems because of the inventors experiences of how to differentiate between
real data and copied data from non-validated sources. They
spent years consulting the Public Safety experts and first responders in the fire
services in local communities and industrial hazardous material teams to consolidate
the PEAC systems features.
The owners/founders of the company
are David Sheesley, John Nordin,
(the author). Our academic training is as follows:
David Sheesley - BS in Physics and
John Nordin - PhD in Chemical Engineering
and a Licensed Professional Engineer
- BS in Electrical Engineering
and Computer Science
- MS in Chemistry and BS in Computer
David is mentioned first because
he was the original Program Manager of the technical staff while all four of us were
employees of the University of Wyoming Research Corporation (UWRC), d/b/a/ Western
Research Institute (WRI) which is located in
. His background experience includes working in many areas, much of which relates
to atmospheric studies, such as:
a physicist at Dow Chemical Co., working at Rocky Flats Nuclear Weapons Plant, Golden,
CO, where processing, purifying, machining and preparing plutonium for the manufacture
of pits was performed, the key component of what became known as triggers for nuclear
weapons. The plant also manufactured other weapons parts using uranium, beryllium,
stainless steel and other materials.
for Atmospheric Research (NCAR),
. This involved a number of different projects such as researching the formation of
condensation nuclei in the tropics and the jungles of
on projects for the US Army. The major
part of his work was in Atmospheric Chemistry involving the validation of model inputs
used to predict long-range transport of natural and man-made material dispersion.
Martin as Program Manager for an Environmental Protection Agency (EPA) contract,
. His tenure included several projects studying atmospheric dispersion at different
locations around the nation for the purpose of calibrating and validating models.
Manager for U.S. Department of Energy (DOE) Oil Shale Environmental Research Program
during the hay days of oil shale research in
Manager for the Hazardous Chemicals Research Group at the UWRC,
performing the Public Safety projects for emergency response.
John Nordin is our
resident expert on most everything having to do with hazardous materials.
His background experience
includes working in many areas:
becoming a co-owner of AristaTek, he was employed as research engineer with UWRC during
1986-1999, Mason and Hanger Engineers from 1979-1986, and senior project engineer
with Betz Converse Murdock from 1971-1978. He
was also the engineer on a water desalination demonstration project for a several
year period after obtaining his PhD degree at the
major project with UWRC other than chemical spill-related work was developing and
testing of a gasifier for garbage, and incinerator for medical waste funded by a private
client, which was later constructed as a demonstration project in
. Other projects were related to environmental problems associated with energy extraction,
a consultant at the Vertec Incineration Superfund Cleanup site in
, and consultant on an environmental cleanup project at a government facility in
with Mason and Hanger Engineering, he was consulting engineer for U.S. Army Corps
of Engineers projects on incineration of explosive-contaminated soils and arsenic-
and pesticide-contaminated soils. He performed on-site assessments of hazardous chemical
contamination at seven army depots and weapons manufacturing facilities and an expansion
of nitric acid production facilities at Radford Army Ammunition Plant.
sampled PCB-contaminated soils and sediments in
superfund site under contract with the EPA.
written computer software for mass/energy balances for TNT thick liquor recovery plant
and for incineration processes. He has consulted on red water and chemical weapons
disposal. He also developed methodology
for feedstock preparation for a U.S. EPA mobile incinerator.
on oil spill release studies at the EPA test facility,
Project Engineer with Betz Converse Murdock, he worked directly with over 100 industrial
clients solving a wide variety of environmental problems.
the lead scientist and POC for UWRC with EPA and industrial participants during the
Kit Fox field experiments conducted at the
on the Nevada Test Site.
the co-developer of the basis for the proprietary vapor dispersion model used in the
PEAC software application.
the day-to-day maintenance and update activities of the PEAC database used in the
PEAC-WMD software application.
is our in-house software expert
and oversees all the software development activities AristaTek undertakes:
provided computer support to administrative and technical groups at the UWRC. Projects
project management information system, accessible from both a PC and a VAX.
interface code for a thermo hydraulics simulation program.
kernel database system to facilitate the rapid development of new database systems.
Windows mail program that permits the easy transfer of files and memos across a network.
designed software, data acquisition design and fabrication, selection of hardware
and equipment, and operations of the integrated systems used in the UWRC field research
program conducted at the
on the Nevada Test Site.
has developed and supported custom designed software for the acquisition and subsequent
analysis of commercial cable TV network systems to allow optimum upgrading and repair
of cable systems.
was the co-developer of the basis for the proprietary vapor dispersion model used
in the PEAC software application. He developed the original PEAC software application
and database implementation on the Apple Newton MessagePad platform using the
script programming language.
developed the original and subsequent PEAC software application and database implementations
for the Windows and Windows Pocket PC operating systems, using the C++ programming
language. And he monitors and co-ordinates all the upgrades as improved data bases
are developed through rigorous quality control procedures.
(the author) uses his chemistry
and programming background to coordinate the activities of the AristaTek staff. His
was a research scientist for US Bureau of Mines and US DOE providing chemistry, software
programming and management support for a series of underground coal gasification (UCG)
field experiments conducted at
during the 1970s and he analyzed all the components of this hydrocarbon extraction
was the UCG consultant during the 1980s for an engineering consulting company located
in the late 1980s and till 1999, he was a research scientist for the UWRC. Activities
included supporting bench scale demonstration projects in oil shale, coal and heavy
oil projects together with the characterization and analysis of all production and
was the Test Director for the Kit Fox Series field experiments conducted at the HAZMAT
Spill Center on the Nevada Test Site working with the industry and government experts
to develop the data acquisition and daily operational protocols.
assisted in the development of the original PEAC database and the subsequent updates
to the PEAC database. As the Chief Operating
Officer of AristaTek, he directs all the technical and operational activities.
All of the owners have been trained
in OSHA Hazwoper classes, and were outfitted up to Level A in order to conduct hands-on
hazardous materials projects outlined above. These technical backgrounds and combined
experience illustrate the fundament knowledge and experience the owners/founders of
AristaTek have used to invent, produce and maintain the patented PEAC-WMD systems. This
brings a unique perspective to the solutions of decision support for the problems
and issues associated with hazardous chemicals and their behavior when released from
storage and transport containers. The following description of the UWRC field experiments
conducted by this team provides additional perspective to show how the PEAC systems
development is unique for Public Safety research and first response.
Team Research Experience
As owners/founders of AristaTek
and former employees of the UWRC, the history of the facility and its staff is traced
back to when it was established in 1940 to investigate heavy oil petroleum resources.
In the 1960s it became a U.S. Bureau of Mines research facility for continued research
in heavy petroleum resources and also the lead
federal laboratory for shale oil research. In the early 1970s the facility started
research programs in tar sands resource recovery and underground coal gasification
development. With the 1973 oil embargo and rising energy prices during the 1970s,
it was a key research facility in developing oil from unconventional sources. In 1978
it became a U.S. Department of Energy Fossil Energy (DOE-FE) research facility called
In 1983, it was de-federalized and
became part of the
also located in
, as the
Corporation. When the so-called oil glut arrived in the mid 1980s, the federal funding
of energy research decreased and Wyomings Congressional delegation suggested WRI address
other research programs that would have more opportunity for funding from the federal
To completely relate how that happened
I would like to relate the following story. One position that David Sheesley held
in the newly formed UWRC in 1983 was the Director of Marketing for research project
development. UWRC had most of its expertise
in energy extraction from unconventional oil resources, also known as synthetic fuels,
and the associated health and safety development that must be developed for new products. At
that time, the lone Congressman for
, Richard Cheney, was visiting UWRC and came into Davids office. The crux of the conversation
was that energy research was going to be reduced because energy prices were much lower
than in the late 70's. David was asked, if UWRC cant continue to receive funding for
National energy extraction research, what other types of expertise does UWRC have
that could be useful to the Nation. The answer was public safety, since UWRC had extensive
experience in assessing and developing the necessary safety and health considerations
to deal with new by-products in oil production. David explained that UWRC staffs past
experience dealing with the environmental and safety problems associated with energy
extraction was valuable experience in understanding hazardous chemicals from any source.
The United States Congress decided
the Nation would use this
resource and research projects were included in the 1986 Superfund and Reauthorization
Act (SARA); specifically Section 118(n), that outlined a DOE funded research program
to investigate and develop new hazardous chemical technology and develop a technology
transfer program for the private and public sectors. Beginning in 1987, the field
projects included in this program were conducted in
and at the Liquefied Gaseous Fuels Spill Test Facility (LGFSTF) located on Frenchman
Flat at the Nevada Test Site, the LGFSTF is now known as the
or HSC within the DOE NNSA.
those not familiar with the Nevada Test Site or the HSC, the diagram in Figure 1 provides
the reader with a perspective of where the projects I will be describing were performed.
The Frenchman Flat location was the site of some of the early 1950s nuclear surface
detonations. The HSC site is now used for different projects, e.g., work performed
by DTRA (Defense Threat Reduction Agency), the national laboratories and used for
the Department of Homeland Securitys radiation training course at the Nevada Test
One of the first projects under
the SARA program that the founders as UWRC employees conducted was an investigation
of 123 hazardous material accidents and report on their cause and the resulting response
actions taken by those in charge. This report (Nordin, 1989) found some similarities
between these accidents. One specific observation was that the responders had used
essentially no prediction tools to develop emergency evacuation zones or consider
what portion of the public was at risk. At a number of these incidents, responders
didnt have appropriate tools available and those that did, didnt have properly trained
individuals on duty that could operate the software technology.
To address national chemical spill
concerns not being met by the SARA implementation, Congress also decided to implement
more research in the 1990 Clean Air Act Amendments (CAAA) that dealt with upcoming
regulations that were to be imposed on industry in the late 1990s and the predictions
of toxic vapor clouds during worst case conditions. The upcoming regulations were
the Risk Management Plan (RMP) regulations to be imposed on industry. It required
industrial facilities, which had threshold quantities of certain toxic chemicals,
to develop a response plan in coordination with local Public Safety officials for
the emergency response to catastrophic release of those chemicals.
Part of the response plan was to
deal with toxic vapor cloud dispersion during the worst case conditions. These worst
case conditions are defined as stable conditions and are characterized by nighttime
conditions when wind speeds are very low, less than 2 mph.
s UWRC was named in Sections 103(f) and 901(h) to conduct these additional research
investigations. These investigations were conducted at the HSC and were to also assist
in development of the data sets and modification of the existing toxic vapor cloud
dispersion models to improve the technology and provide reliable prediction tools
for those having to respond to or plan for accidental hazardous chemical releases.
These activities were to be jointly funded and directed by the DOE and EPA.
A hazardous chemical problem might
be what is different between worst case conditions and conditions that might occur
during the daytime and when winds are considerably higher than 2 mph. Chemical vapor
dispersion is a complex and involved subject but is essentially related to the amount
of turbulence (mixing) exhibited by the atmospheric conditions. Primarily, the turbulence
arises from two factors: (1) surface heating during the daytime causes rising air
from the warm surface to create turbulence, and (2) horizontal air movement (wind)
across a surface, particularly a surface with buildings, cars, vegetation, causes
the air to tumble and create turbulence which affects dispersion of airborne chemicals.
The lack of turbulence, from ground heating at nighttime and low winds speeds, reduces
how fast a toxic vapor cloud disperses or mixes into the surrounding atmosphere, and
the vapor cloud has a tendency to persist and be carried a longer distance downwind.
The name worst case condition is used since the chemical vapor cloud doesnt disperse
rapidly and individuals downwind are at risk of exposure to higher concentrations
for longer distances.
The interesting fact is that in
previous field research studies conducted before these experiments, there was only
very limited information or datasets available for the mathematical modelers to compare
their results against, i.e., validate their models. Most of the previous research
and the resulting data sets had been created measuring vapor cloud dispersion in neutral
conditions, i.e., daytime with wind speeds in excess of 10 mph. In addition, these
field experiments had been conducted at sites that represented essentially very flat
surfaces, so turbulence from wind tumbling over obstacles was limited and not as representative
of the real world as would be desired.
The first field experiments were
conducted in the summer of 1993 and were designed to demonstrate and investigate certain
dense gas behavior could be observed by releasing smaller volumes of a heavier-than-air
simulate without having to resort to the large volumes used in earlier field experiments.
characterize the HSC site with regards to the transition from neutral to stable atmospheric
conditions that occurred at sun set. This was basically to measure the wind direction
change, if any, as the conditions changed from >10 mph to < 2mph.
a suite of new real time gas sensors to ensure that the gas concentrations could be
measured at 1-second intervals as the vapor cloud passed through the instrumentation
The objectives in the 1993 experiments
were achieved and design was started on the next series of experiments.
The dispersion investigations culminated
in the Kit Fox Series and UWRC was funded by industry,  Department of Energy, and
Environmental Protection Agency to include investigations of dense gas releases in
both neutral and stable atmospheric conditions. Chemical releases across three different
surface configurations (roughness), e.g., the surface configurations were to represent
(1) very flat conditions with no obstacles to promote turbulence, which is the normal
appearance of the HSC dry lake-bed, (2) moderate or medium sized obstacles that would
represent crops or low vegetation, and (3) higher obstacles that would represent the
buildings and superstructure you might find around a refinery or chemical facility.
A question the reader may ask is
how do you simulate vegetation or even better yet, how do you simulate a refinery
or industrial facility on a dry lakebed? The answer is we had the help and input of
some very capable engineers and scientists that do a lot of work in wind tunnels.
The technical advisory group was composed of some internationally recognized experts:
Gary Briggs, NOAA/EPA,
- Developer of the Briggs sigma coefficients for Gaussian dispersion.
- Co-developer of DEGADIS (dense gas
model used in EPAs ALOHA application).
- Custodian of the American Petroleum Institute (API) HGSYSTEM and HEGADAS Model.
- Co-developer of the Britter McQuaid Equations, one of the first sets of empirical
formulations for predicting dense gas vapor dispersion.
The first task was to develop a
grid of small rectangular flaps that would represent low vegetation that might be
found around a refinery or chemical plant. Dr. William Snyder used the EPAs Atmospheric
Research and Exposure Assessment Laboratory (wind tunnel) at
Research Triangle Park
to do the initial iteration of the grid development. It this process, different sizes
and spacing configurations of rectangular flaps were setup and air flow measurements
were made to characterize the air flow and turbulence over the grid. The objective
was to develop the size and spacing that would replicate the normal flow that has
been measured in previous field experiments. Portions of the size and spacing measurement
work was repeated and compared to the RTP results using a wind tunnel located at the
and operated by Dr. Jerry Havens.
tasks to replicate the flow characteristics of a large-scale facility were done by
UWRC through contracts with Cermak, Peterka and Petersen, Inc. (CPP) at the wind tunnel
. The work involved taking a scale model (1:300) of an actual Exxon refinery and measuring
the flow and turbulence across the scale model in the wind tunnel. Once the flow characteristics
had been measured, Dr. Petersen and his staff used the technique of spacing larger
rectangular flaps till they could replicate the same flow characteristics measured
for the scale model (Figure 2).
dispersion investigations culminated in the Kit Fox Series that was funded by industry,
 Department of Energy, and Environmental Protection Agency. This was the first
large scale field experiments (see Figure 3 below) conducted to understand dense gas
behavior in worst case conditions (stable atmospheric conditions).
The fabrication of the test grid
as shown above (Figure 3) and below in Figure 4, took a considerable amount of time
and effort to install. The small rectangular flaps cover an area over 9 acres in size
and amount to ~6,700 flaps. Each had to be properly spaced on the row and each row
had to be separated properly and the flaps set in a straight line. The large flaps
that represented the super structure of a facility was fabricated out of 2 sheets
of 4 x 8 plywood attached to 2 square steel posts set in the dry lake-bed surface.
tall pointed objects at the front of the test grid (Figure 4) are modified Irwin spires
and are based on a technique used in wind tunnels to promote the initiation of turbulence.
Without the spires at the front of the test grid, the test grid would have had to
extend several hundred meters upwind. These spires helped to jump-start the turbulence
that would have entered the test grid with several hundred meters of small flaps.
5 and 6 recorded some of then UWRC staff, now co-owners of AristaTek, as they installed
different portions of the instrumentation and control systems used in the Kit Fox
The project was a true collaboration of academic, industrial and governmental researchers
coming together to achieve a common goal. The individuals identified in Figure 7 are
just a fraction of the different participants involved in the project that attended
the pre-test review.
As described earlier, the objective
was to conduct dense gas releases across three different surface configurations during
both daytime and nighttime conditions. One problem was that there was limited access
to the test site and considerable time was involved in the installation of the rectangular
flaps that represented different parts of the surface configurations. Doing the most
complex surface configuration first, which included both large flaps and the 6,700
smaller flaps, solved this problem. Once these first series of releases were completed,
the large flaps, as seen in Figure 4, were removed during a single morning and another
series of releases were conducted over several days with just the small flaps in place.
These small flaps represented a release where only vegetation was the surrounding
type of obstacles and the amount of turbulence from wind motion was reduced.
The final surface configuration
involved removing the 6,700 small flaps, which took about 3 days, compared to the
4+ weeks to install those flaps. Then the last series of releases were conducted where
the surface was basically the dry lakebed, which is about as flat as a table top and
twice as hard.
testing involved using carbon dioxide as a surrogate dense gas, which was stored as
a vapor in a set of large tanks constructed back in the 1980s for other experiments
(Figure 8). These tanks were connected to the test grid via a 500 foot long 12 in
line that dropped into an 8 in line that ran another 580 feet to the release point.
release point was located underground in the center of the large flaps to simulate
a ground level release inside the super structure of a refinery or chemical processing
facility, Figure 9.
The instrument array consisted of
90+ gas concentration sensors positioned in four downwind arrays to measure the real-time
concentration as the vapor cloud moved downwind from the release point. These sensors
were subjected to a daily calibration procedure prior to each days releases, which
in turn were used to develop the QA/QC data associated with the data reported at the
end of the experiments.
array of meteorological sensors was installed in and around the array to allow the
characterization of the atmospheric conditions prior to and during each release that
was performed. These meteorological sensors included the typical mechanical anemometers
as shown in Figure 10 that provide wind direction and speed at multiple levels at
specific locations, which were co-located with temperature sensors to measure the
temperature profile at these locations. This information was used to characterize
the atmospheric stability during each release.
addition to the mechanical anemometers, a series of 3-axis (an example is shown in
Figure 11) and 2-axis sonic anemometers were installed at multiple locations and levels.
These sonic anemometers provided high-resolution measurements (100 reading/sec averaged
to output 10 reading/sec) in the horizontal plane (2-axis units) but also in the vertical
axis (3-axis units) to allow direct measurement of the turbulence within the test
addition to the meteorological instrumentation within the array, there was a 24-m
tower adjacent to the array that allowed installation of instrumentation at 8 levels
to fully characterize the atmospheric conditions during the experiments (Figure 12).
This tower had additional instruments that recorded humidity, soil temperature, solar
radiation, net solar radiation and barometric pressure.
The last element of the data acquisition
system was the recording of measurements related to the release of the carbon dioxide
vapor from the tank farm through the delivery system and eventual release in the test
grid. This involved monitoring of pressures and temperatures at multiple points and
also the remote control and positioning of different valves in the proper sequence
to delivery the proper amount of vapor during a release. The flow rate measurements
were done with two separate and independent systems to allow cross checking of results.
Testing consisted of multiple releases
during a single day. This was a combination of short duration releases, approximately
20 seconds in duration, and what were called continuous releases, that lasted from
2-8 minutes in duration. Because the prevailing winds entering the test grid had a
tendency to shift, a critical aspect of the testing was to monitor these ambient winds
and start a release when the wind was lined up with the centerline of the test grid.
This would provide the greatest cloud capture by the downwind instrumentation arrays
as the cloud dispersed after being released. A large number of releases were performed
with over 70 being captured almost entirely within the downwind instrument arrays.
After the field-testing was completed
and the test grid dismantled, the data calibration and initial analysis was performed.
This was a long and complicated process, which was delayed when the EPA temporarily
terminated funding for the project at the end of September 1995. With considerable
prodding and pleading, the funding was eventually restored and the two-volume data
report was prepared and delivered to the industrial participants, DOE and EPA.
1986 SARA legislation that put
into the business of investigating hazardous chemical technology also created the
State Emergency Response Commissions (SERCs) and the Local Emergency Planning Committees
John, Survey of 123 Toxic Chemical Release Accidents in the United States and Applicability
to Future Development of Department of Energy Nevada Spill Test Facility Programs, Contract
DE‑AC-0l-88FE61472, Western Research Institute, Laramie, WY, January 1989.
Jerry Havens along with Dr. Tom Spicer are the researchers that maintain the DEGADIS
vapor dispersion model. The DEGADIS model is the dense gas model used in the EPA/NOAA
CAMEO Suite ALOHA vapor dispersion model.
Environmental Research Forum (PERF Project 93-16), which comprised the following ten
companies: Allied Signal Corporation; Amoco Corporation; Chevron Research and Technology
Co.; CITGO Petroleum Corporation; Clark Oil and Refining
; Exxon Research and Engineering Co.; Marathon Corporation; Mobil Research and Development
Co.; Phillips Petroleum Co.; and Shell Research and Development Co.