Call & Nicholas, Inc. (CNI), an internationally recognized geotechnical engineering consulting firm, has been providing a wide range of engineering services to the mining industry since 1981. Originally established in 1979 as R. D. Call, Inc. by Dr. Richard Call, the name was changed in 1981 when David E. Nicholas became a principal and partner in the firm. Today, a full staff of geotechnical engineers, engineering geologists, and technicians, with experience in both open-pit and underground mining, provides expertise in:

• Feasibility studies
• Open-pit slope angle recommendations
• Underground rock mechanics and mining method selection
• Open-pit and underground displacement monitoring
• Cost-benefit analysis
• Hydro-geologic evaluation
• Waste dump and tailings dam stability evaluations
• Site investigation and foundation recommendations for waste dumps, leach pads, and water-retention dams
• Engineering geological studies
• Geotechnical instrumentation and blast vibration monitoring
• Operations improvement and training for blasting and construction
• Evaluation of the mechanical properties of geologic materials
• Foundation recommendations for mine facilities

CNI's Tucson facility includes a fully equipped rock testing laboratory with soil testing capabilities. Testing services are also available through the Rock Mechanics Laboratory at the University of Arizona, under the supervision of CNI personnel. All data analyses are performed in-house. CNI is committed to providing our clients with the highest level of service and the most cost-effective solutions to each individual problem. CNI's outstanding reputation has been built on the expertise and integrity of our staff, and their dedication to excellence.

CNI's integrated, geotechnical approach to problem solving involves geology, rock mechanics, soil mechanics, and hydrology. Studies encompass data collection and analysis of data, preliminary hydrologic and structural definitions, the final analyses and conclusions, and the final recommendations. Data collection, for both open-pit and underground mines, is aimed at being able to perform a probability analysis. The founders of CNI instituted the use of probability analyses in the early 1970s. A cost-benefit approach is utilized to provide economically optimum slope angles for open-pit mines.

Using CNI's integrated approach, the geotechnical studies become an ongoing part of mine planning rather than a single, isolated event. In many cases, geotechnical studies are done in the initial stages of mine planning, when exposures of rock are limited and a great number of assumptions must be made; time and budget constraints normally do not permit an extremely detailed subsurface investigation. When the geotechnical program is incorporated into long-term planning, data collected during the development of the mine can be used more effectively in conjunction with mining operations. The defined geotechnical program then becomes an integral part of mine development and is responsible for providing updated recommendations for the life of the mine.

CNI is an advocate of training the client's technical staff at a property. Active participation in the data collection and analysis enables the mine staff to better understand and implement the rock mechanics recommendations; they are then able to recognize the changing conditions in the mine that might necessitate a re-evaluation. By using the client's available technical personnel to their fullest potential, our engineers can concentrate on providing the expertise needed in the analysis phase of the study.

CNI's engineers are assigned to specific projects based on their individual areas of expertise, years of experience, and availability. However, each engineer is educated in all phases of the engineering process, and open communication is encouraged, enabling principals and staff engineers to actively participate in all phases of a study. This practice allows CNI to make maximum use of our available resources, ensuring the availability of a strong team of experienced professionals dedicated to solving our clients' geotechnical needs.