Recovery of short levied customs duty: Show Cause Notice triggers duty, interest and penalty with adjudication and enforcement mechanisms. Recovery of customs duty short levied is effected by issuing a Show Cause Notice requiring payment of duty, interest and penalty; adjudication follows quasi judicial personal hearings with specified monetary limits for different grades of officers, while validation provisions designate who qualifies as the proper officer for assessment and enable statutory enforcement measures including adjustment, detention and sale or recovery as arrears of land revenue.