August 7, 2020
Position: Principal Contaminated Land Consultant
Organisation: AECOM
One-liner: There is no single country that I would say is more contaminated than another as it’s all a matter of scale and the nature of contamination
The Interview
What processes are put in place in order to remediate a contaminated site?
STEM Girl Power
There are generally two ways that a site gets contaminated. The first is a result of historical activity and long-term use of a site for industrial processes, like a chemical manufacturing plant.
The other way sites tend to get contaminated is if there is a spill, for example a tank gets a hole in it and as a result, fuel spills into the environment.
The two different ways the site has been contaminated are treated in different ways, but the first step is to identify the extent of the contamination. Then you work out what the contaminant is and what part of the environment has been contaminated; for example, we may have fuel in groundwater.
Once we know the nature and extent of the contamination, we can work out how best to remediate it, based on the specifics of the situation. Before we go and dig it all up, we prepare a remediation plan, which details where the contamination is, how deep, what type, how much volume of soil needs to be excavated, how much water needs to be treated and what types of treatment are required. It also describes what sort of sampling we need to do to confirm the remediation has been successful.
Let’s take an example: fuel from an underground petrol storage tank has leaked into groundwater. Typically, we would remove the leaking tank, dig out the soil we see has fuel on it and then take samples of the freshly excavated walls to confirm it is all removed. If all the results pass, we backfill the hole with clean soil, or put in a new tank.
The soil may be able to be treated—which takes more time and costs—or it can be removed to landfill.
What kind of advice do you most commonly give about managing contaminated land?
Emma, Babinda State School
Maintain your equipment and address identified contamination early—if you can stop contamination from occurring in the first place then it’s a lot easier to manage when it does go wrong. Often contamination is the result of a leaking pipe which a client has known about for a long time or it’s a result of historical practices.
What is it like to work at remote sites away from Townsville?
STEM Girl Power
Awesome! Going away for work is great.
In the last couple of years, I’ve been on helicopter rides, boat rides, charter planes and other flights to get to where I need to be for work. Remote work can be hard, as you’re away from home and you miss your friends and family, but they tend to pay you more for this work! You often get to meet interesting people and work in beautiful places—and if you get your timing right you can have a few days off to sight-see!
Work on remote sites is often challenging but also highly rewarding because you solve problems with what you have rather than what you need, which can help build resilience and resourcefulness and comes in handy later in your career. Once, we were doing hydrocarbon remediation on a remote site and we wanted to add some nitrogen to our soil. There was no fertiliser plant nearby to source the nitrogen, so we used manure from the local cattle yard. It worked well and we were able to remediate the soil.
You provide training to newcomers in your industry—why do you think this is so important?
STEM Girl Power
When newcomers, particularly graduates, start, we have to teach them everything. University gives you the skills to think for yourself and see things through to the end. The training we provide teaches people how to talk to clients, build the business and win work (which means you keep your job), write reports interpret results against a guideline and understand your company’s internal systems.
The industry we work in can be very dangerous. Health and safety training is important on work sites. We deal with heavy machinery and chemicals, and if you don’t know what you’re doing you can seriously injure yourself or others and that’s why training is so important.
Managing contaminated land comes by building your experience under the guidance of mentors—this is true for most professions.
Remediation of contaminated land can take a long time. How do you make sure it is working?
STEM Girl Power
We start with a remediation plan which sets the expectations and desired outcomes at the beginning of a project, so we know what the end point is that we want to achieve. Then we set up a network of monitoring points so that we can check how the remediation is going.
For example, if we had a leaking fuel tank in the ground and we removed it, we would set up a network of groundwater monitoring wells to check the concentrations of hydrocarbons in groundwater are decreasing. If we find hydrocarbons in the groundwater, we put another well in a bit further away and down-stream of the contaminated well to see how far the contamination has travelled. Every 3-6 months we collect and test groundwater samples to check the contamination levels. If the levels are increasing, we search for other contamination sources. If the levels are decreasing, we continue monitoring until the concentrations are within the acceptable limits. Sometimes when the levels increase, we have to remove the contamination so that nature can do the rest.
What got you interested in remediation of contaminated land?
STEM Girl Power
I studied agriculture at university and was very interested in soils—they’re fascinating!
I fell into my job by accident as a friend offered me a role investigating contaminated land. I found it really interesting and I’m still here, 18 years later. It’s not something they specifically teach in school or at university, as is the case with many jobs.
What keeps me interested is that no two sites are the same and I have a huge amount of variety in my job. Contaminated land doesn’t just mean dirt—I investigate groundwater, soil gas, landfill gas, soil, sediment, surface water, biota (fish). I can be in the office, out on the road, out in the bush, on a construction site, on a military base, in a boat, in a chopper, four wheel driving, digging a hole, watching a drill rig or excavator—and I get paid for it.
Early in my career I had the pleasure of remediating a contaminated site on the Sydney Harbour foreshore. I used to get to site early and have my breakfast overlooking the water every morning. I have been to some pretty amazing places and every day is different. I think it’s the best job ever and it’s never boring.
What country has the worst contaminated land and what conditions caused it?
Bernice, Southport SHS
Every country has contamination. Contamination comes in so many forms and is not limited to land; it also includes water, air and groundwater.
Contamination can be physical, chemical, solid, liquid, vapour or gas. Loss of containment (where there has been a spill or a dam wall has broken and spread contamination to the environment) and untreated discharges from industrial processes are probably the two biggest contributors to contaminated land and waste disposal practices are probably the biggest contributor to pollution. Nuclear contamination is probably the worst kind of contamination and possibly the hardest to treat.
There is no single country that I would say is more contaminated than another as it’s all a matter of scale and the nature of the contamination.
Are the techniques for managing contaminated land changing with new technologies?
STEM Girl Power
Yes! Sometimes we modify or combine old technologies into new systems to treat different contaminants and sometimes we generate new technologies to treat new problems. The company I work for is currently developing new technology to treat PFAs (per- and poly-fluoroalkyl substances) in water.
What is it like to work for an international company from Townsville?
STEM Girl Power
It’s great to be able to work with clients to solve their problems. Working for an international company provides opportunities for travel and sharing ideas with colleagues both locally and internationally. It gives you access to some of the best engineering talent in the world and we get to work on some really big jobs because we’re a big company and have the people to do the projects. I get to work on projects not only in my backyard but across Australia and sometimes overseas as well. Working for a big international company also means lots of policies and procedures which can sometimes get a bit complex.
Bio
Carina Jakobi is a Principal Contaminated Land Consultant for AECOM in Townsville with eighteen years’ experience in environmental consulting, specialising in contaminated sites. She has worked on a variety of sites in Australia and New Zealand and has experience with developing and overseeing small to large scale environmental site investigations and remediation programs.
Carina has experience in contaminated land risk assessment and application of control measures and mitigation of risk associated with contaminated land matters.
Carina has worked on sites ranging from green field sites and due diligence assessments to heavily contaminated industrial sites including smelters, petroleum retail and wholesale sites, gas works, military sites, mines, airports and galvanizing plants. Other experience includes quality system auditing, contract management and project administration for large projects.
Carina’s specialist areas are project management, assessment and remediation of contaminated sites.
Carina’s job involves soil, groundwater, surface water and sediment sampling to assess the environment for contamination and provide advice and strategies to clients to manage and remediate contamination so it doesn’t get into the wider environment.