Welfare Association under concept of mutuality

Hello

I have a query related to taxation of welfare Association

1) interest on corpus fund deposit
2) interest & penality on non/delay payments received from members

shall I treated above as income and taxable in the hands of association.

my view is

1)corpus fund is an capital in nature, interest earned from that deposit is also added to capital shall not treated as revenue item hence it is not treated as income, please correct me if I am wrong.

2) I don't know how to deal please suggest.

It's urgent

Thank you