Cleanse rubbish tip checked by centre of operations (7)
I believe the answer is:
baptise
'cleanse' is the definition.
('cleanse'->'baptize' is in my internal thesaurus and 'ize'->'ise')
'rubbish tip checked by centre of operations' is the wordplay.
'rubbish' indicates anagramming the letters (a poor quality or rubbish spelling of the letters).
'checked by' indicates putting letters inside.
'centre of operations' becomes 'base' (I've seen this before).
'tip' anagrammed gives 'pti'.
'pti' put within 'base' is 'BAPTISE'.
(Other definitions for baptise that I've seen before include "Christen" , "First Roman Catholic sacrament" , "Give name" , "Administer the first RC sacrament" .)