Although there are many different geophysical methods, small-scale surveys all tend to be rather alike and involve similar, and sometimes ambiguous, jargon. For example, the word base has three different common meanings, and stacked and field have two each.
Measurements in geophysical surveys are made in the field but, unfortunately, many are also of fields. Field theory is fundamental to gravity, magnetic and electromagnetic work, and even particle fluxes and seismic wavefronts can be described in terms of radiation fields. Sometimes ambiguity is unimportant, and sometimes both meanings are appropriate (and intended), but there are occasions when it is necessary to make clear distinctions.

The role of field measurements in risk assessment and the control of natural geohazards, in engineering design, construction and operation of engineering facilities has grown in the past and will undoubtedly grow in years to come with ever increasing demands on the engineering skills of people involved in these activities. It is therefore necessary to give those interested in instrumentation and measurements an opportunity to meet regularly to exchange ideas and experiences and to stimulate further advancement within field instrumentation.

The purpose of this book is to provide the reader with guidance on the development and implementation of cost-effective and defensible environmental sampling programs that are designed to collect data needed to
• Defi ne the nature and extent of contamination

• Calculate baseline human health and ecological risk
• Identify contaminant migration pathways
• Predict rates of contaminant migration
• Evaluate the viability of potential remedial alternatives
• Support treatability testing
• Assess the effectiveness of a remedial alternative during implementation
• Determine if remedial action objectives have been met
• Dispose of waste material properly

The Geological Association of Canada (GAC) recognizes that its field trips may involve hazards to the leaders and participants. It is the policy of the Geological Association of Canada to provide for the safety of participants during field trips, and to take every precaution, reasonable in the circumstances, to ensure that field trips are run with due regard for the safety of leaders and participants.