As you also wrote in the tags, this links to both land transformation and land occupation: The quarry occupies 10'm2 to produce 300' t/a -> this is occupation. Since it is operated for 13 years, you have also to model land transformation, 10'm2/13*300' t gives you the transformation per product amount. Strictly speaking, you even need to model transformation from (e.g., forest) to (maybe industrial site), and then after closure from industrial site to what you assume the quarry becomes.
