Received a 1099-C for a non-recourse mortgage loan. how do I indicate that it is not taxable.

If the second mortgage was a non-recourse loan used for the purchase of the home, then it should say the debtor is not liable for repayment of the loan in box 5 of your 1099-C. If this is the case, TurboTax will automatically remove the forgiven debt as income on your tax form. 

If it doesn't, but instead says you are liable for the debt in box 5, you'll likely have to call the lender to have them look into it and potentially reissue a 1099-C with the correct information; otherwise, the IRS will assume you owe taxes on the forgiven debt.

Thanks for your response. To complicate the issue the statement received was not a typical 1099-C form it was a single page with a 1099-A and 1099-C written out like it would have fit into standard forms with the boxes listed and corresponding information for each box. The 1099-A had a box 5 stating I was personally responsible for the debt but the 1099-C did not even list a box 5 it skipped over that number. Not sure how to interpret that.