The provision corresponds to the legal obligation to remove Ipiranga’s underground fuel tanks located at Ipiranga-branded service stations after a certain use period (see Note 2.m).
Changes in the provision for asset retirement obligation are as follows:
| 2017 | 2016 | 2015 | |||
| Initial balance | 77,564 | 74,716 | 70,802 | ||
| Additions (new tanks) | 537 | 483 | 625 | ||
| Expense with tanks removed | (15,432) | (2,785) | (3,949) | ||
| Accretion expense | 2,105 | 5,150 | 7,238 | ||
| Final balance | 64,774 | 77,564 | 74,716 | ||
| Current | 4,799 | 4,563 | 5,232 | ||
| Non-current | 59,975 | 73,001 | 69,484 |