Bit of a random one this which turned out to make for a decent mooch, not the most historic or interesting but a bit of industry not usually seen nonetheless. It involved a spontaneous trip to see the Rainham ROC post, to find it locked. The ROC post closed in 1991 and fell on the site of a small industrial premises which is now an empty wasteland next to the quarry and a lagoon formed by previous quarrying works.
We then became interested in the nearby quarry which appeared to be active. OS mapping from 1958-1965 shows a sand and gravel pit to have existed on the site, although it disappears from earlier mapping, suggesting operations began around the late 1950s or early 1960s. It's still very much in use today, which made it a bit of a sneaky one being perturbed on several occasions by various lights and a van driving fairly close at one point. It's interesting to see that this part of the world is still prime territory for the aggregate quarrying industry as it has been for centuries, and as hi-tech as the machinery looks, it is essentially just an elaborate way of digging up sand (correct me if I'm wrong). Made for a fairly brief yet interesting look around whilst trying not to sink into the slurry.