Requested samples arrive at the library, where they are identified, boxed, and preserved. The footage interval and total depth are recorded, a KGS call number is assigned, and the sample set is immediately added to the KGS database and becomes available for examination.
Selected samples are then washed and dried in a sample-washing machine. Located above the machine are three illuminated exhaust hoods, which serve to remove any fine particles, moisture, or odors resulting from preparation of the samples for washing. Located on the exhaust hood are two switches: one for lights and the other that activates hood fans, opens the makeup air exhaust louvers, and energizes the makeup air unit.
Unwashed well cuttings located in sample bags are poured into 4 inch x 4 inch stainless-steel washing pans in an enclosed sample preparation area to minimize any dust emissions. Each pan is numbered to keep track of the individual sample. The bottoms of the pans are made with stainless-steel mesh and are available in three different sizes: 60, 80, and 160. The mesh size used is determined by the size of the well cuttings being processed. Sixteen pans containing unwashed samples are placed onto a 16½ inch x 17 inch stainless-steel washing tray. A cover measuring 16½ inches x 16½ inches with a stainless-steel 60-mesh opening is fitted over the top of these pans. The cover prevents cross-contamination between pans during the washing process while allowing the water to freely wash the cuttings.
The automated sample washer has 10 conveyor speeds, which can be adjusted depending on the size, quantity, and condition of the samples. At the middle speed, it has the capacity to wash 3,200 feet of well cuttings per hour, or approximately 20,000 feet per day. The sample trays advance through the washing compartment, which has three rows of four spray nozzles for a total of 12 nozzles. The water velocity of each row of spray nozzles is adjustable. The washed samples then advance into the drying oven to pass under heating elements regulated by a thermostat located on the outside of the machine. The heat is monitored with a thermocouple inside the oven. Samples emerge from the drying oven and advance onto the drying platform until they are removed with insulated gloves and placed on racking to cool. Well samples can also be placed wet onto the racks to be air-dried. A microswitch located at the end of the drying platform shuts off the conveyor and the heating elements when tripped. This prevents sample trays from inadvertently exiting the cooling platform. An emergency shutoff switch is located on the front of the machine for safety purposes. Additional switches located on the front are for turning the water and sample-drying heating elements on or off.
Materials washed out of the cuttings, including fine particles and drilling mud, go into a three-tier sediment trap. The trap was designed with removable stainless-steel trays to minimize contamination of the surrounding environment and enable efficient disposal of the materials washed out of the sample pans. This also protects sediments from entering the facility’s plumbing system and causing damage and blockage. The sediment trap is mounted on wheels for convenient accessibility and maintenance.
Labels bearing the interval and call number of each individual sample are prepared and placed on plastic cards. The cards are inserted along with the samples into 3 inch x 5 inch, water-resistant, plastic, zip-top envelopes. The envelopes are arranged by depth and placed into uniform boxes 3½ inches wide by 6½ inches deep by 24 inches long. These boxes are then labeled with the operator’s name, farm name, well number, Carter coordinate location, county, elevation, depth interval contained, and a numerically sequenced box number. They are then shelved on pallet racking, and their box number and position on the shelf noted in the database.
Traditionally, well samples were washed by hand. This method was grossly inefficient, laborious, and unproductive. In 1980, Patrick Gooding, the manager of the Kentucky Geological Survey Well Sample and Core Library, sent 47 letters to other geological surveys in the United States and Canada asking about methods used in processing samples. Twenty-five replies were received, revealing that only two repositories had any type of automation for washing samples. Their methods were cumbersome and used natural gas to dry the samples; it was not what was envisioned. As a result, Gooding set out to design and build an automated, electric-powered sample-washing machine. Concepts were examined and plans for the machine were developed. Ideas for efficiency, productivity, and labor cost-savings were presented to the KGS director, and in 1981 funds became available. The machine was fabricated at a cost of $14,300 and is the only one of its kind. It is located in a room specifically designed for processing samples at the Well Sample and Core Library.