Site investigation covers a broad range of activities, from small scale investigations for domestic subsidence claims to the investigation and remediation of brownfield sites and sophisticated exploratory work for major projects such as the Jubilee Line Extension.
Site investigation companies have traditionally employed either civil engineers (for their knowledge of how a structure relates to the ground) or geologists with an interest in geotechnical engineering and an understanding of how variations in the ground may affect the performance of a structure. In both cases, a postgraduate degree in geotechnical engineering will eventually be required for career progression although one or two years' experience before postgraduate study will probably be of significant benefit. A graduate whose first degree included modules in site investigation or geotechnics should be well placed to find employment with a site investigation specialist.
Best placed are graduates with engineering geology first degrees, where the syllabus will often overlap with postgraduate studies.
This said, site investigation companies are increasingly keen to employ graduates with specialist environmental science skills, such as knowledge of contaminated land investigation and the chemistry of soil and groundwater.
A large site investigation contractor will often be employed to carry out an investigation by the geotechnical division of a multidisciplinary consultant. The consultant will typically design and direct fieldwork, as well as interpreting the investigation, while the contractor is required to provide a 'factual-only' report comprising the results of the investigation - such as borehole and trial pit logs - but not providing any interpretation of the results. A number of specialist employment agencies provide freelance site investigation engineers to contractors for factualonly site investigation.
A graduate engineer working for a site investigation contractor will find that much of his or her work is site based and may have little opportunity for understanding and interpreting the results of the work. However, he or she will gain experience in a wide variety of exploratory methods and how these are applied to a range of different soil and rock types, in addition to the satisfaction of being part of large civil engineering projects.
Assuming the contractor has a division providing an interpretive reporting service, opportunities should arise later to become more involved in design work - after a period of sitebased work, or on completion of a masters degree. This career path, if followed by postgraduate study, will be particularly attractive to the multi-disciplinary consultants involved in specifying and interpreting site investigations.
Fitting between the geotechnical division of the multi-disciplinary consultant and the site investigation contractor are small and medium-sized companies which act as contractor/ consultant or site investigation specialists. A site investigation specialist will typically work with civil or structural engineering firms that do not have in house geotechnical skills. It will design the investigation, carry out all fieldwork and laboratory testing and interpret the results.
There may also be an ongoing role as a geotechnical consultant beyond the site investigation itself. And on contaminated sites there may be involvement in designing and monitoring a scheme or remediation.
Engineers working for a site investigation specialist will have the satisfaction of being involved in the entire site investigation process, including the interpretation of the results and design of foundations and retaining structures.
As in other areas of civil engineering, there is a shortage of well qualified engineers in the site investigation sector. As well as an appropriate academic background, prospective site investigation engineers should be able to adapt a scheme of investigation to the findings as the work proceeds. While analytical abilities are important, so too are common sense and imagination. Site investigation engineers will often find themselves at the sharp end of a project and being the first visible sign of activity on a site often requires tact and diplomacy.
Steve Branch is managing director of LBH Wembley Geotechnical & Environmental