Ian Gregson (GHD)

Reflections
by ALGA Life Member, Ian Gregson (GHD)

My career in the contaminated land industry started in 1989 with Dames & Moore – there was a time when virtually everyone in the industry seemed to have worked for D&M at one time or another! Like many others in the industry, my background was in other areas (mining environmental, construction supervision but with an unplanned but surprisingly relevant degree in Bio-Resource Engineering from the University of British Columbia). I was hired primarily for my project management and site supervision experience, and after a few months “initiation” putting dirt in jars on the former Mobil Oil Terminal remediation project at Pulpit Point, I moved to Melbourne to manage the Bayside Remediation Project – another former oil terminal. A very quick induction into two of the most significant remediation projects of the day!

While we had some gurus such as Roger Parker and Peter Nadebaum to look up to, we had very little Australian guidance to refer to. ANZECC 1992 Guidelines for the Assessment and Remediation of Contaminated Sites had not yet been developed, the Vic EPA environmental auditor scheme had not started, and we relied heavily on guidelines and procedures developed in the Netherlands and USA EPA, often going back to first-principles. For the Bayside project, our team included hydrogeologists, geotechnical engineers, and a project chemist. We wrote our own D-base programming to manage data, and had our own drafter on site to keep up with the figures. With a sub-contracted mechanical engineer, we even developed and had our own soil-vapour extraction unit with catalytic destruction manufactured for the project! Heady days indeed.

While some aspects of the industry were nascent, others were well developed (based on USA experience), with D&M having a particularly strong OH&S culture. The entire site team had base-line medicals, with one member showing up high blood-lead levels apparently from too much exposure to leaded petrol (from back-yard mechanics - not as a result of remediation or site investigation activities…).

Over the following years, the amount of guidance available for the industry has increased exponentially, with guidelines available or prescribed for almost all aspects of what we do – this has contributed to a much more consistent standard across the practice, but also seems to have taken much of the thought out of the process, except for leading edge specialist applications on the more complex projects. It is harder for the average practitioner to get as involved as was the case in the early days. When Mobil divested their retail outlets across Australia in the early 90’s, we had virtually the entire staff of D&M, including draftsmen, scientists and secretaries, out doing site assessments with shift-teams working into the night with hand-sketches and correction tape to prepare progress reports!

Some aspects have shown significant advancement over the decades, particularly with assessment and management of petroleum hydrocarbons. A sound body of understanding of biodegradation processes has developed in parallel with more sophisticated investigation techniques such as high-resolution vertical profiling and site characterisation using in-situ analytical tools. Monitored natural attenuation and source zone degradation have become more than a “do-nothing” approach. Dig and dump is no longer the default remediation strategy. In other areas, such as management of asbestos, it seems to be one step forward, two steps back, and we struggle to disseminate the understanding of the risks of asbestos in soil that were quite clearly articulated in the enHealth technical monograph “Management of asbestos in a non-occupational environment”, which was published in 2005. The Western Australia Department of Health has been a leading regulator in adopting standard practices for assessment and management of asbestos in soils, but despite adoption of their 2009 guidelines in the NEPM, their 2021 update has not received widespread acceptance by other Australian regulators.

On reflection, the contamination assessment, remediation and management industry has been interesting and rewarding throughout my career, and I am thankful for the hard work of colleagues, regulators and industry organisations in providing conferences and papers for sharing of information and experiences, and encouraging an objective of continual improvement. The pace of change keeps up, with new contaminants and technologies constantly on the horizon, so that the challenge for new starters is in no way diminished from that which we, nearing the end of our careers, can look back on with a certain fondness!