concrete manufacture “As an example - the manufacture of plastic optical lenses for glasses produces finely ground plastic waste which would normally be sent to landfill or incinerated. Many years ago, when the USA was engaged in what was then 'billed' as an anti-Comm***st action in Asia, a vast base as built (Cam Rann Bay) Amazingly, they had to import sand from elsewhere, as that available locally would not 'bind' with the cement used, to manufacture concrete. Sand typically comprises 30 per cent of any concrete mixture.