Coal Heap. The picture is of Queen Elizabeth and King George Dock in the background and the storage area for cheap imported Eastern European coal in the foreground.  All but the bottom left hand side of this area is within the specified square (TA1528).  The area of the coal heap is huge - about 16 hectares (39 acres).  The picture was taken (from memory) at about 1200 feet.
<a rel="nofollow" class="external text" href="https://www.geograph.org.uk/profile/307">Andy Beecroft</a>
From <a rel="nofollow" class="external text" href="https://www.geograph.org.uk/photo/68936">geograph.org.uk</a>