Capital in recycling event being green (7)
I believe the answer is:
naivete
'being green' is the definition.
(green can mean naive or innocent)
'capital in recycling event' is the wordplay.
'capital' becomes 'ai' (resembles 'A1', old-fashioned term for excellent).
'in' indicates putting letters inside.
'recycling' indicates an anagram.
'event' anagrammed gives 'nvete'.
'ai' placed into 'nvete' is 'NAIVETE'.
(Other definitions for naivete that I've seen before include "natural simplicity" , "Greenness" , "lack of sophistication" , "Ingenuosity" , "State of inexperience (French spelling)" .)