That's a very well written article.

Here's a link to the government's view on the broad situation - the stuff's a vital element of concrete - which you find almost everywhere nowadays.

http://www.countryside.gov.uk/alsf/

I've briefly discovered that there are many common attitudes and positions that are shared among conservation issues. Trying to save a henge, for instance, runs into the same kind of opposition as trying to save a dragonfly. Fortunately, as the material - stone mainly - is so resilient then the 'time frame' is much longer. A gallon of pesticide (eg) would kill dragonflies more or less overnight - but only dent a henge.

That recent comment about 'trying to herd cats' is apt - but I'm off on the tiles !