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.