I've communicated with Dr. Eric Wade (Local Mining Engineer) and been given permission to publish his paper "The Broomhill / Amble Undersea Project". Anyone who has worked down a coal mine in the North East will be at least familiar with Dr. Wade's name from the inevitable "bait time" discussions of potential mining futures.
The particular copy of this paper I have (borrowed from Alan J, forum member) is missing a few illustrations which I hope to find and add at a later date. Original publication I believe is the early 1980's but will confirm this.
The paper is now here:
The Broomhill / Amble Undersea Project
The post script to this is that an attempt was made to access these reserves from Ellington but was abandoned - just as they reached the area.