Officials may issue notices, carry out surveys in some big cases where no response has come Income Tax officials could soon be at your doorstep if you have deposited a huge amount during the note-swapping exercise last year, and have not yet explained the source of the cash. “We have tried to keep the exercise non-intrusive. But if people have not come forward, then some kind of verification is needed especially in cases that involve deposits of large sums,“ a senior income-tax department official told ET. Under the `Operation Clean Money', the I-T department had sent out SMSes and e-mails to about 18 lakh people who deposited over `5 lakh each during the 50-day window from November 10 to December 30, because the desposits did not tally with their income. The depositors were asked by the I-T department to explain the source of the money by logging in to its portal. By February 15, about 7.3 lakh people responded to the emails and ex plained their deposits. According to th