In many countries, geologists, engineering geologists and geotechnical engineers are engaged in solving the problems due to geological hazards. In the Philippines, one of the most common geological hazard that occurred in the past and continues to threaten both the human lives and properties is the mass movement. The lack of unified procedure for field data gathering during applied/engineering geological site investigations was found to be one of the reasons why mass movement became catastrophic, such as frequent landslides along Kennon Road.
To prevent this kind of disaster, the Philippine government, through the Department of Environment and Natural Resources (DENR) and the Environment Management Bureau (EMB) came up with Administrative Order No. 2000-28, otherwise known as the Engineering Geological and Geohazard Assessment Report (EGGAR). To address this issue, a unified procedure for applied/engineering geological site investigation is formulated to come up with a comprehensive database for geologists and engineers that will help in the design and construction of land development projects.
The unified procedure is based mainly on the following standards and schemes, namely American Society for Testing and Materials (ASTM) and American Association of State Highway and Transportation Officials (AASTHO) standards for soil testing; American Geological Institute (AGI) Data Sheets for Geology in the field, laboratory and office by Dutro and others (1989); British Standard 5390; British Standard Code of Practice CP 2001 (1957); Liu Evett’s Visual-Manual Procedure (1997); Hack’s Slope Stability Probability Classification Scheme; International Society for Rock Mechanics (IRSM) Suggested Methods; Laubscher’s Geomechanical Classification Scheme for the rating of rock mass in mine design; Rock Classification System for Engineering Purpose by Louis (1987); Z.T. Bienniawski’s Rock Mass Rating (RMR) system (Geomechanics Classification) in Engineering (1988).This unified procedure is divided into two phases. The Phase I - Initial Site Investigation, involves geological and engineering geological aspects, both of which can be assessed systematically by using the Engineering Geology-Initial Site Investigation Form No. 1. The Phase II - Detailed Site Investigation and Laboratory Analysis, includes the analysis of the climate factors and use of results from the Initial Site Investigation. This phase also includes the conduct of laboratory tests (as recommended in Phase I). Ultimately, the detailed investigation will identify the possible slope failures and the geometry of mass movement. In addition, appropriate mitigating measures in the analysis of slope stability will be formulated.