xmlns:atom="http://www.w3.org/2005/Atom"
1. In this Schedule, “background quantity” means, in relation to the release of a substance resulting from an activity, such quantity of that substance as is present in—
(a)water supplied to the site where the activity is carried on;
(b)water abstracted for use in the activity; and
(c)precipitation onto the site on which the activity is carried on.