Head of department is asking for payment and leaking (11)

'leaking' is the definition.
The answer and definition can be both related to change as well as being present participle verbs.
Perhaps they are linked in a way I don't understand?

'head of department is asking for payment' is the wordplay.
'head of' indicates taking the first letters.
'asking for payment' becomes 'charging' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
The initial letter of 'department' is 'd'.
'd'+'is'+'charging'='DISCHARGING'

'and' acts as a link.

Can you help me to learn more?