• Soil Consultant for a Stormwater Management Plan developed for the FBI Academy in Quantico, VA. Used RUSLE to calculate the approximate soil loss due to on-site construction.
• Responsible for county, state and federal water quality permits for the Fordham Street Wetlands Creation in Chillum, MD.
• Participated in a long-term ecological investigation to determine the stability of the Milestone Fen, Montgomery County, Maryland. Principal tasks include performing on-going water quality monitoring of surface and ground waters to assess potential impacts from urban development.
• Aided in evaluating operational performance data in support of litigation for bio-tower failure.
• Participated in calculations for Deicing Fluid and Runoff at PDX Airport, Portland, Oregon.
• Participated in RTDF groundwater sampling for the U.S. Air Force at Dover Air Force Base, Dover, Delaware. Work included the implementation of micro-purging techniques using bladder and submersible pumps; and collection, preservation, and shipment of samples.
• Conducted groundwater monitoring activities for three RCRA sites and two landfills at Fort Belvoir, Virginia.
• Assisted in Geophysical Surveying at Aberdeen Proving Grounds, Aberdeen, MD. Used survey equipment and a magnetic and cable locator. Assisted with the EM 31 and EM 61.
• Prepared several proposals and associated cost details related to water resource projects.

The Army's chemical demilitarization program was activated at the proving ground in 1986. Partly because of the 1988-1989 trial and conviction of three senior Chemical Research, Development, and Engineering Center (CRDEC) employees on charges of not complying with federal environmental laws, environmental awareness has become even more sensitive at the proving ground. Millions of dollars annually go into cleaning-up, restoring and preserving the natural beauty of the Aberdeen Proving Ground.

Due to the sensitivity of the area in which this project is implemented, we must be very careful of where and how we disturb the grounds. The areas we are working in contain discarded ordinances, some live, some not, scattered throughout. Another company, HFA, went out to the site before we were given access. They swept the site with specific ordinance locators and marked all they found. Although these are marked, some may have been overlooked; thus, we must be instructed what to do if an ordinance is found. Do not touch it! Call HFA and they will arrange for removal. Now, it is off to the site for the initial setup. Upon arriving at the site, the first step was to set up the survey area. This was done using a tripod, transit and rod, (skills learned in BE 221). A wooden stake was driven into the ground at each corner of the 200 ft. x 300 ft. plot and at 100-foot intervals along the perimeter and middle. Before driving the stake into the ground, the ground had to be tested for the presence of buried metals. We used a Magnetic and Cable Locator, more commonly referred to as a magnometer, to check for buried metals, specifically ordinances. This machine is operated by simply turning it on, placing it near something of known metallic origin (i.e., steel toe of boots) to verify that it is working properly and then swaying it above the place where the stake should be placed. If no sound is made as the magnometer passes over the desired area, it is apparently safe to drive the stake into the ground.

After all the needed stakes were set, pin flags were placed every 3 feet along the line (0, 0) to (300, 0), (0, 100) to (300, 100), and (0, 200) to (300, 200). Measuring tapes were laid out every 3 feet (connecting the appropriate flags) to create a 200 x 300 foot grid. The grids are necessary to make sure the instruments survey every square foot of the area in question. The instruments we used were the EM31-MK2 and the EM61. The EM31-MK2 is a ground conductivity meter with the data logger incorporated into the machine. The EM61 is a metal detector, which detects both ferrous and non-ferrous metals.

The EM31-MK2 maps subsurface features associated with changes in the ground conductivity such as geological variations and/or groundwater contaminants using a patented electromagnetic inductive technique. The technique makes the measurements without electrodes or ground contact. This feature enables completion of surveys under most geological conditions including those of high surface resistivity such as sand, gravel and asphalt. The EM31-MK2 is effective to depths of about six meters.

Some advantages of the EM31-MK2 over more conventional resistivity methods are the speed in which surveys can be conducted, the precision with which small changes in conductivity can be measured, the continuous readout and data collection while traversing the survey area, and the easy download of data. Ground conductivity and in-phase measurements are read directly from the data logger screen and can be downloaded into computer programs like Surfer. This downloaded data can be developed into a map of the area surveyed and geologic variations will be easily noted.

The EM61 detects both ferrous and non-ferrous metals by using a powerful transmitter to generate a pulsed primary magnetic field in the earth, which induces eddy currents in nearby metallic objects. The eddy current decay produces a secondary magnetic field measured by the receiver coil. By taking the measurement at a relatively long time after the start of the decay, the current induced in the ground has fully dissipated and only the current in the metal is still producing a secondary field. The responses are recorded and displayed by an integrated data logger. The EM61 detects a single 200-litre (55 gal) drum at a depth of over 3 meters beneath the instrument, yet is relatively insensitive to nearby cultural interference, such as fences, buildings and power lines. The response is a single, sharply defined peak, greatly facilitating quick and accurate location of the target. Depth of the target can usually be estimated from the width of the response. This particular project was exciting because of the hazardous conditions in which we worked. We observed unexploded ordinances up to 16 inches in diameter. When the data from the EM31-MK2 was collected and graphed, it was apparent where trenches existed over 50 years ago. With the data from the EM61, we found buried batteries and drums. With this data, the Army can continue to restore the environment of its bases and in turn clean up the Earth.

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