Cyflwynwyd y Lefi Agregau yn 2002 fel ‘treth werdd’ ar godi agregau – carreg galed, tywod, graean a siâl – at ddibenion masnachol.  Mae cyfran o’r refeniw a godwyd wedi’i ddefnyddio i gynnal prosiectau cyfalaf mewn cymunedau y mae gwaith codi agregau wedi effeithio arnyn nhw.
The Aggregate Levy was introduced in 2002 as a ‘green’ tax on the commercial extraction of aggregate – hard rock, sand, gravel and shale.  A proportion of the revenue raised has been used to support capital projects in communities affected by active aggregate extraction.