Having worked as a geo-environmental consultant for over ten years, I am accustomed to the challenges of site work. Wet weather, temperamental monitoring instruments, flat tires, 4am starts – all experienced and overcome. Perhaps then it was timely that my expectations were challenged.
I, as Principal Geo-Environmental Consultant for GGS, had already worked with the client, Sweco, on many UK projects performing continuous monitoring and baseline monitoring at several large residential housing developments near former landfills and shallow mine workings. The data and guidance we provided were so highly valued by the client that they invited us to work for them again, this time in Gothenburg, Sweden. This was a welcome testimony to the standard of our work, a great opportunity to work in Scandinavia, and a potentially enormous logistical challenge, given the current situation with Corona virus in the UK and EU.
Monitoring was to start in November 2021, when Covid-19 travel restrictions were strict. It was also a 2000-mile round trip by van and ferry to deploy instruments in six monitoring wells and acquire vital data on ground gas and groundwater behaviour. A positive test could have cost time and resources, so the pressure was on. Thankfully, after testing negative several times, acquiring a covid passport and filling out numerous forms, I was allowed out of the UK and began the long drive to Gothenburg. Winter weather was imminent, meaning grey skies and few photo opportunities. My route did take me over the impressive bridges in Denmark and into Sweden, and of course, through beautiful countryside, which made a pleasant change from the M6.
I met the project lead and local council representative on site at Frihamnen docks on my first visit. Both insisted that any potential ground gas hazards were fully investigated. This is my favourite type of client; informed and committed to due diligence. Frihamnen is previously flooded land comprised of canals that have been infilled, making high water levels a challenge too. Knowing GGS’s reputation for industry leading monitoring and interpretation, the approach was to conduct continuous ground gas, water and flow monitoring to provide all lines of inquiry and develop a robust conceptual site model. One key objective was to capture falls in pressure to understand ground gas behaviour during key driving mechanisms.
As I was planning the return trip, covid travel rules changed 48hrs before my departure. I ordered covid-19 tests in advance, but they didn’t arrive in time, which resulted in finding a testing site in Rotterdam on the return leg before being allowed back into the UK for Christmas! Then, just to add a little more excitement to my trip, Storm Barra made a spectacular appearance resulting in a three-hour delay to the ferry crossing. At GGS, we usually get excited when a storm passes over as we get to see the response from ground gases on multiple sites. However, I do usually prefer being at my desk these days.
Thankfully there was a positive aspect of the storm, as it created a significant pressure drop and the ideal environment for potential ground gas migration and worst-case conditions to inform the risk assessment. In summary, the monitoring completed provided an interesting, extensive and robust time series data set that will provide certainty for the client to establish the actual risk posed by ground gases, including requirements for remedial design.
What I like most about working in environmental monitoring is the diverse range of projects I work on, no two of which are the same. Every client and location have a unique set of characteristics which guide the approaches we take. Despite the additional challenges presented by the Gothenburg project, I enjoyed it. Challenges were identified and solutions were found, some even originating from the challenges themselves. Thanks Storm Barra.
The following pages include news articles, videos, guidance notes and white papers on a range of ground gas related topics which we hope you will find of interest. Please browse through but if you can’t find something on your particular issue of interest, we’d be very pleased to hear from you so we can put that right.
Landfill gas consists of approximately 50% methane, so methane monitoring is essential to best practice waste management.