The Louisiana oil spill Geographic Information System
Baseline Samdin~ and Analvsis Study
Another major component of the LOGIS database is the Baseline Sampling and Analysis (BSA)
study. This new product provided a means to evaluate the current petroleum hydrocarbon
concentrations in Louisiana's coastal zone sediments where an oil spill could occur. Over a
three-year period, four contractors are performing sampling to provide Global Positioning
System (GPS) coordinates and laboratory analysis of samples taken throughout the study area.
First year field work for the sampling component included pinpointing monitoring points by GPS
on land and in water and performing sample collection and analysis. Years two and three
involve re-sampling the points established during year one.
The sampling study concentrates on areas exhibiting a high probability for oil spills. LOSCO
ranked areas in terms of probability as follows:
- Areas adjacent to Gulf shipping lanes
- Areas adjacent to inland shipping lanes
- Major crude oil pipelines at points of greatest hazard (e.g. under navigation channels, through
areas subject to subsidence and areas surrounding major terminals)
- Areas surrounding oil fields, refineries, major crude oil tank farms, and other fixed sources
ACT 740 emphasizes the importance of protecting sensitive environmental areas that require
additional sampling points. The sampling frequency, number of sample points, and the number
of laboratory tests required for the samples are subject to change based on the results of the
initial year's sampling.
To assist field crews with their sampling, LOSCO and the contractor developed a Microsoft
Access database. Using laptop computers, field crews are able to input field data directly into a
digital format, including Latitude and Longitude with corresponding UTM coordinates from the
GPS. As the study progresses, each contractor's database shows the cumulative samples
collected. Sampling progress is monitored by displaying the sample coordinates stored in the
database as an ArcView GIS theme superimposed on the system base map.
The ability to quickly display this type of geospatial information has proven to be an invaluable
asset for project management. This ability allows management to observe differences between
actual and proposed sample locations, monitor sampling progress visually, and evaluate
projected completion for sampling operations.
Pit and Barge Studies
Two specific studies identify oil sites that pose a threat. They are the pit and barge studies. The
purpose of the first effort, the pit study, is to identifi and locate abandoned oil production
facilities and apparatus that pose a potential threat for creating an oil spill through either natural
or accidental causes. Erosion and other problems frequently expose oil production elements in
the coastal waters, including oilfield waste pits, pipelines, manifold headers, and tank batteries,
that were formerly buried or on land. Additionally, the cribbing around a well may decay or fall
away, leaving the well exposed. These exposed elements also are susceptible to damage by boat
traffic.
Contractors for LOSCO noted all apparatus and pits in the field with this potential and
determined the positions of these features with GPS. The observable data recorded for each
location includes feature type, observations on the feature, and in some cases, photographs or site
plans. The total number of sites inventoried to date is approximately 16,200, all cataloged in the
working LOGIS database.
The purpose of the second study, the barge study, is to inventory abandoned vessels and barges
in Louisiana's coastal waters. The inventory located containers of oil waste (primarily
abandoned vessels) requiring immediate attention and potential containers for oil waste which
could become a hazard. Such containers may hold oil or other hazardous wastes that could be
released into the environment or are potential repositories for future illegal hazardous waste
dumping. The inventory allows LOSCO to access various data including location of the vessel,
identification of the vessel and its owner (if determinable), and a priority based on hazard
potential. The inventory includes 802 vessels located in three zones of the project study area.
Data was converted from an existing Microsoft Access database of barge and pit locations into a
standard framework for direct integration with ArcView. Progress is monitored by the display
the pit and barge coordinates stored in the database as an ArcView theme superimposed on the
system base map.
Conclusion
The LOGIS database has already proven to be a tool with many applications. The next challenge
will be distributing and maintaining such a large volume of data. LOSCO and its contractor
already are planning for distributing the system over the Internet. However, serving more than a
terabyte of data via FTP or through a Web browser currently is not feasible. The team now is
evaluating its data set priorities and researching new data compression techniques so they will be
prepared when it becomes time to distribute the data.
With a broad range of data incorporated into the system, LOSCO is able to meet all its needs
from oil spill planning to response to damage assessment. Therefore, while the tankers and
barges continue to carry oil into and out of the Bayou State, the people of Louisiana can let the
good times roll. Through preparation for the worst, LOSCO is preventing it. As a result,
LOSCO is protecting the best resources the state harbors: its people and its environment.
Acknowledgements
LOSCO would like to thank all private entities and government agencies that have contributed to
and supported the LOGIS effort. The LOGIS project would not be successful without
cooperation from both government and the private sector.
