Country diary: Seaham, Durham: With every tide the sea erases a little more of the decades of industrial abuse

When Dawdon pit closed and the sea dumping of colliery waste ended, Blast beach resembled the surface of an alien planet so much so that it was chosen as the location for the opening sequences of the 1992 movie Alien 3. Since then a massive clean-up campaign has transformed the shore into a pleasant place for a Christmas-morning walk, graced today with dazzling sunshine. At the bottom of the cliffs there are still traces of industrial archaeology: some topsy-turvy geology with boulders brought to the surface from strata below the magnesian limestone cliffs; colourful mineral incrustations; a faint whiff of sulphur. But with every tide the sea erases a little more of the decades of industrial abuse, and also delivers small, sought-after gifts.