The mudflats here have witnessed tens of millions of years of history and experienced countless tides rising and falling, forming a unique ecological landscape.
On the train out to meet Spencer, I had marvelled at the Pitsea horizon, a nonsensical Thames estuary hillside towering over the mudflats, a Brecon Beacon of waste.
What you see when you glance at this environment are a bunch of what appear to be tunnels or mounds here, and these are made by the gases produced by the microbes living in this mudflat area.