Payments for utility easement sales do not get reported as income on your tax return. Instead, the payment lowers your basis in the property. That only becomes important later when you sell the land. The only time you report the payment as income is when the payment exceeds your basis in the property. Please follow this link for more information. https://www.irs.gov/publications/p544/ch01.html#en_US_2015_publink100072442
However, the buyer has reported the sale to you (and the IRS) on Form 1099S. The IRS will often send letters to the taxpayer in this situation and attempt to add the sales price to your taxable income. If this happens to you, you'll need to write back to the IRS and explain the payment was for a utility easement. Unfortunately, there is no way to report the sale on your tax return that could avoid this situation.