The Ordnance and Explosives (OE) detection process for the Formerly Used Defense Site at Camp Beale, California currently employs a combination of Geophysical, Global Positioning Systems (GPS), and GIS technologies. First, this paper will explain how these technologies work together to detect subterranean OE, specifically unexploded ordnance (UXO).
Secondly, this paper will outline GIS applications for OE site archive research analysis, 3D spatial analysis, narrowing and sectoring the OE search areas, management and analysis of OE field operations, OE statistical analysis and prediction, general OE program management, and distributed GIS access for management and the public.
Before getting into the more technical objectives, here is some background information about the former Camp Beale to help put the rest of the paper into context.
The Formerly Used Defense Site (FUDS) Camp Beale was once used as a military training area by the Department of Defense (DoD). “DoD purchased the property in 1942, buying 87,000 acres from 150 families, and used it for a "full service" combat training facility, utilizing many types of ordnance. The training facility included bombing, rifle, mortar, demolition, and machine gun ranges.
Between 1959 and 1964, DoD sold 64,000 acres back to the public, retaining 23,000 acres for Beale Air Force Base. While DoD performed surface clearances of the ranges prior to selling the 64,000 acres, the possibility exists that unexploded ordnance may remain in some of the former training areas.” (Reference: www.campbeale.spk.usace.army.mil)
The overall mission of the Camp Beale project team is to reduce the risk of unexploded ordnance (UXO) contact with the public, which includes over 1,500 private landowners, then detect and remove all residual Ordnance and Explosive (OE) materials. In order to accomplish that, the Camp Beale project currently employs a combination of geophysical, Global Positioning Systems (GPS), and Geographic Information Systems (GIS) technologies.
“The former Camp Beale site encompasses approximately 64,000 acres located in northern California immediately east of Beale Air Force Base, straddling both Yuba and Nevada counties. The site is located approximately 45 miles north of Sacramento and 20 miles east of Marysville, CA.” (Reference: www.campbeale.spk.usace.army.mil)
At the former Camp Beale, a common way that the U.S. Army Corps of Engineers (USACE) detects subterranean OE, and more importantly UXO, is through the use of digital electromagnetic geophysical instruments. There are many digital electromagnetic instruments and many ways in which the geophysicist can scan the ground using these devices. For instance, at the former Camp Beale typical ways of scanning the ground with these instruments can be through the use of hand-held instruments, or the instrument can be mounted on a cart and pulled across the surface. In either case a GPS will be connected to the instrument and will record geographic points in coordination with digital readings as measured output by the geophysical instrument. An on-board computer is used to record these GPS coordinates and the corresponding digital measurements.
The data is then compiled and passed to a GIS where a geophysicist processes and performs analysis with the data set. The geophysicist then creates color contour maps that visually depict anomalies detected by the instrument. Based on their electromagnetic signatures, the geophysicist can then “pick” a set of these anomalies and their geographic points that might be an OE item or collection of OE items. These points are compiled by geographic area and uploaded to a GPS. The GPS is then used in the field to navigate to each of the “picked” points. An audible magnetometer is then used to reacquire the exact spot where the geophysical instrument detected an anomaly, and then the OE expert field crew dig each anomaly. Each anomaly dug is recorded with what was found, if anything. If something is found then the area is again rescanned geophysically to assure no OE items were under the original item(s) found.
In order for the OE detection team to properly use the geophysical instruments, a series of seeded test plots are needed. The results of these seeded tests allow the OE detection team to choose the correct geophysical instrument for a given detection task. First, potential test plot areas are isolated at Camp Beale using the project GIS. This GIS analysis isolated these areas based on geology, topography, vegetation, other obstacles such as trees, rocks and other structures, suspected OE areas such as former ranges and target areas, and real estate parcel Right-of-Entry granted to the USACE by the parcel owners. One of the main ideas to these tests was to test each instrument in each of the main geologies of the Camp Beale site area. Secondly, once the areas were determined, more specific areas were sectored using a 300’ X 300’ grid in each geology area. Thirdly, areas were surface swept for OE item by OE experts for safety then each grid was seeded with inert OE items at different depths and orientations. The OE item types used were the OE item types the detection team expected to find at Camp Beale based on historical military records for the site. Lastly, a total digital geophysical OE detection process survey is then performed on each seeded test plot grid. Based on how each instrument performs, the detection team can then more accurately determine what instrument to use to assure maximum detection capabilities in a given geology, expected OE type(s), and at expected depth ranges.
One of the first steps the USACE uses on an OE FUDS site is to perform an Archive Search. The Archive Search Team searches, retrieves and reviews every possible document, photograph, map, and air photo about Camp Beale, as well as interviewing people from former military personnel that were stationed at Camp Beale, to present occupants of the former Camp Beale area. This information is compiled and assessed toward the goal of finding every relevant piece of evidence of military activity that would lead the team to all suspected geographic areas of OE, OE type, and possible UXO contamination.
The GIS plays a pivotal role during the Archive Search. All historic air photos and maps are to be reviewed and certain features are to be assessed and digitized. These specific historical features include craters or disturbed surface areas, historic structures, former ranges and targets, former property boundaries, and other features that are relevant evidence to military activity, especially OE activity. Each set of these features is categorized by year. For instance, at Camp Beale the years of historic air photos and corresponding digitized features are 1941, 1943, 1947, 1953, 1958, 1962, and 1964.
Once these features are captured into the GIS, change detection analysis can be performed against differing years of historical data and against current data as well. One way of performing this analysis is through the use of 3D GIS visualization.
A 3D elevation model is then generated and historic air photos, targets, and ranges overlaid. Then the photos and features can be added and removed chronologically for 3D visualization of change detection analysis. With Esri ArcGIS 8 3D Analyst, an observation point can be established that mimics where a soldier might have stood at a range firing point or points. The downrange target can then be seen exactly how a soldier might have seen the target, range, obstacles, and terrain historically.
In addition, with Esri ArcGIS 8 Spatial Analyst, a simulation can be created based on a munitions possible trajectory, range, terrain, obstacles, and geology. For instance, a 2.36 inch rocket can travel a certain distance if aimed at a given azimuth, inclination, and fired at a given point and elevation toward a target. The simulation model will give a good idea where the 2.36 inch rocket might have landed as well as if it buried itself into a geology and how deep it might have gone. If we know that 2.36 inch rockets were historically used, specifically at that point with a given target, then we can create an “artificial range arc area” where the 2.36 inch rockets might have landed. This information can be used to further narrow the search area for expected UXO, UXO type, and depth.
To further narrow and sector the OE search areas over the 100 square miles of land, other historical and current information is analyzed. GIS coverages such as ranges, target areas, areas of known and more dangerous OE types, and disturbed areas are used again, however, current areas that cannot be OE surveyed such as pavement, sidewalks, paved roads, rivers, lakes, new structures, and other certain features are areas that can be excluded from the OE search areas. Other features can be either exclusion areas or special consideration areas for OE investigation such as endangered or specially categorized species and their habitats or culturally sensitive areas. Other areas are excluded by the GIS because they have been determined that they might interfere with the electromagnetic geophysical investigations. These areas include power lines, underground pipes, certain other utility features, metal fences, and areas with a great density of ferrous geology. These areas will be investigated or managed by using other available OE processes or methodologies. Still, the GIS can isolate other areas that lend themselves to specific geophysical instruments due to features such as hand-held instruments rather than cart type instruments because of dense vegetation, large rocks, high terrain slope, extremely uneven terrain, and other geographic features.
A large part of the overall mission of the Camp Beale OE Remediation effort is to reduce risk to the public caused by UXO. The priority is to reduce higher risk areas first and then work toward areas that have evidence of relatively lower risk. To aid in this effort the Camp Beale GIS can analyze risk factors to locate and define the higher to lower risk areas. These risk factors include data such as higher and lower population densities, current and future land use, proximity to current and future populations such as schools, churches, shopping centers, certain other populations, access through roads and trails, or lack of access because of fences, walls, or dense vegetation as well as other access restricting features. Other risk factors include areas where known UXO or OE items have been found to date; this includes areas where items were found without an OE specific investigation effort or what has been coined “incidental OE finds”. In addition, experienced OE experts can visit the site and find evidence of military activity which can then be recorded via a GPS and assist in further focusing the OE search areas.
Of course, one of the best ways to reduce risk to the public is to detect and remove UXO items by conducting a complete detection and removal process during OE field operations.
In order to capture and manage field operations, data about the field operations needed to be collected in a central location. To do this, one site-wide OE database is created to store all current and historical attributes for field operations such as OE surface sweeps, vegetation removal, digital geophysical surveys, reacquisition and digging of anomalies and the actual items found, other field operations, and cost and scheduling for OE field operations.
To populate the OE database, and instead of bringing data back from the field to be put into the database, the database is brought to the data collectors through the use of hand-held computers. First, the field computer database is designed to be seamlessly compatible with the OE repository database on a server. Entry forms are then made on the “front” of the database with pull-down menus for easier access to data choices. These menus minimized chances for human error, and the database has required fields to minimize chances for data gaps. Since the data is input at the source, the process time is severely decreased rather than filling out hard-copy forms in the field and then transcribing the data into the database. Along with this solution, all past OE items encountered and their nomenclature are used to create a standard. This provides nomenclature consistency, especially for OE items that can be found in pieces or a partial condition. But one cannot predict every attribute variable of OE items, including OE scrap. To solve this, a field operator can look through the OE item list, and if the item description is not in the list or does not fit the item found then the operator would be allowed to enter in a proposed nomenclature. The proposed nomenclature would later be assessed and quality assured by other OE experts, then added back to the OE item “pick list” as a legitimate and consistent description for future field use.
In order to be able to record these field operations and their attributes for a GIS, spatial parameters for each operation needed to be defined. Typically the spatial parameters for a geophysical operation are in the form of a grid that serves as the boundaries for a total geophysical survey. Because Camp Beale has chosen to record OE items and other features in feet units, the Camp Beale team decided to use the NAD 83 State Plane Coordinate System. In choosing this coordinate system as the standard for the project, we created a site-wide Master Grid System based on the same coordinate system. This provided a way to track field operations on a consistent, site-wide basis that all stakeholders could use. We then wanted to make it relatively easy to use and easy to Quality Assure/Quality Control (QA/QC). In turn, we decided to divided the site into LARGE, MEDIUM and SMALL grid cells and uniquely identify each grid cell with an alphanumeric Cartesian coordinate system. Each LARGE grid cell measures 10,000’ X 10,000’ and has a prefix of the letter “L”. Within each LARGE grid cell contain MEDIUM grid cells. These grids are 1000’ x 1000’ cells and have a prefix of the letter “M”. Within each MEDIUM grid cell are SMALL grid cells. The SMALL grids cells are 100’ X 100’ and has a prefix of the letter “S”. After the prefix annotation, the alphanumeric Cartesian coordinates are annotated, for example, LD2 is a LARGE grid cell located along row D and up column 2. This coordinate concept is repeated for the other grid cell sizes of MEDIUM and SMALL respectively. The unique identification of any 100’ X 100’ or SMALL grid cell is created by stringing together the three grid sizes, local alphanumeric Cartesian coordinates with their respective prefix annotations. For example, a possible Master Grid ID to annotate a 100’ X 100’ cell might be: LD2-MG3-SH4. By establishing a Master Grid System before field operations occur, it prevented future creation of other grids and grid identifications that would result in database problems, such as duplicate grid IDs. Also, by dividing the entire site into these common grids, the GIS and it’s associated OE database has the immediate ability to track each OE field operation by geographic areas that are composed of uniquely identified grid cells.
However, many times these grid cells do not fit reality. One of the spatial dilemmas encountered is that the Master Grid System does not always fit all of the areas that have OE field work needed. These other field operation areas include roads cleared of OE, sampling grids, firebreaks cleared, sampling transects, and other geographic areas, none of these areas spatially fit the Master Grid System. Additionally, there are partial grids that have to be shown partially investigated and/or cleared because they have a real estate parcel boundary splitting them. In any case, we need to display them accurately. This becomes a large challenge when we need to make a user-friendly project management GIS system for the Camp Beale Team and the public. In order to show the status of areas that have a given field operation conducted, we have to make sure that all non-Master Grid System grids are uniquely identified, then compare the Master Grid System GIS layer to a layer that consists of the areas of OE operations that do not spatially fit the Master Grid System GIS layer. The new GIS layer produced from that query compares it to the real estate parcel boundaries layer and cuts the applicable grids to those boundaries. The resulting layer shows the OE field operations areas accurately displayed in any way wished. This becomes a dynamic or “living” GIS layer that is reprocessed every time, and in turn, is updated every time. This dynamic layer enables the user to view where different methods of investigation were used and at various depths. At that point any of the other GIS layers can be overlaid and compared, queried and spatially analyzed with the new dynamic GIS layer, such as OE items encountered.
Even though there are always going to be areas where the Master Grid System will not fit, if possible, minimizing the non-Master Grids will make this OE field operation tracking system work better. It is not the intent of this OE field operation tracking system to make the Camp Beale OE investigations conform to these geographic boundaries. However, the tracking system and its performance belong to the end-users and it is the end-users who will use it; this should be taken into consideration when deciding how to proceed with future OE investigations. There are ways of compromising on this point. For instance, if a larger geographic area is needed for OE field operations and in order to use the Master Grid System, any combination of 100’ X 100’ grids can be used so long as the collection of unique IDs are part of a database look-up table linked to the specific OE field operation(s).
The overall concept is to use the site-wide Master Grid System and OE database as a basis for keeping track of OE field operations to show where we have investigated, where we have not investigated, where we need to investigate, and so that we do not duplicate effort in the same geographic areas. This is a better method, rather than trying to keep track of shrinking polygons, and the resulting flurry of versions, that represent areas left to investigate; this concept is sometimes referred to as “footprint reduction”. By tying unique identifiers to unchanging or “permanent” boundaries such as Master Grids, it passes the tracking work to relational database software that was designed to keep track of unique IDs and continually changing or multiplying attributes.
Another very useful tool the Camp Beale GIS offers is the use of geostatistical OE sampling. One of the goals of OE sampling is to be able to use geophysical instruments to scan samples of a larger OE area with the intent to characterize the larger OE area based on the results of the sampling. The sampling is a way of determining whether to survey the entire site or, based on the sampling evidence, declare the area too low of a UXO risk to the public to conduct a total geophysical survey.
Through the narrowing and sectoring the OE search area process, the GIS is able to locate the best areas in which to sample for OE items. Additionally, the GIS will also tell the Camp Beale team the expected OE types, and expected depths based on firing points and known targets. After the sampling is conducted, the GIS can take the resulting sample data and with Esri GIS Geostatistical Analyst, geostatistically make a prediction of where more OE items might be found and what the density of those items might be.
Some useful project and program management data recorded in the OE database are equipment used, manpower used, time to complete operations, and cost. These data are used as a tool to determine future costs for operations in a given geographic area, ability to predict and schedule time and manpower required for specific future operations in that geographic area, as well as equipment needed. It can also generate summary reports such as average cost to detect and remove OE by acre, or a report of cost per acre using a certain geophysical instrument.
The Camp Beale Real Estate Database is used to track data such as parcels, parcel owners, contact information, parcel occupants, Right-of-Entry status, OE finds by the public, and other information. This database is also linked to the GIS as part of the overall tool set.
Additionally, the USACE needed to be able to have a data provider perform approved QC procedures before delivering data. The USACE also needed to be able to QA the delivered QC data. The GIS has a major role during these QA/QC Procedures by plotting OE items and investigation area boundaries and cross check the attributes about those plotted features.
Another project and program management tool provided by the GIS and databases is that after QA/QC, data is analyzed and archived as the site-wide record and repository of OE field operations, OE items found and their status, funding spent, and other important information that needs to be documented.
The need for public education and awareness about project status and OE/UXO safety at the Formerly Used Defense Site Camp Beale is evident. In order to aid in this effort, an Internet based GIS was created and linked to the Camp Beale public website. This public GIS assists stakeholders and interested parties to be informed of the status of the project, and allows searching and analysis of real estate parcels against the site boundary and suspected OE areas. These past and current Camp Beale area real estate parcels and attributes about the parcels are tracked in the Camp Beale Real Estate database that is linked to the GIS. This allows the project team to create mailing lists by geographic areas and criteria, it also allows searches for real estate parcels in which field work has been conducted and maps of the exact areas that a field operation or combination of field operations have been conducted.
Furthermore, an Internet GIS will be created that would give more spatial analysis power to the Camp Beale Team. For example, a password protected Camp Beale Team Internet GIS site can be linked to both the OE database and real estate database. This would allow the team to discover the most current granted Right-of-Entries for privately owned parcels or keep track of daily OE investigation progress and what OE items were found from anywhere.