11.

Asset Retirement Obligations

Asset retirement obligations ("ARO") relate to the Lost Creek mine and Pathfinder projects and are equal to the current estimated reclamation cost escalated at inflation rates ranging from 0.74% to 2.44% and then discounted at a credit adjusted risk-free rates ranging from 0.33% to 7.25%. Current estimated reclamation costs include costs of closure, reclamation, demolition and stabilization of the well fields, processing plants, infrastructure, aquifer restoration, waste dumps, and ongoing post-closure environmental monitoring and maintenance costs. The schedule of payments required to settle the future reclamation extends through 2033.

The present value of the estimated future closure estimate is presented in the following table.

Asset Retirement Obligations

December 31, 2018

Change in estimated reclamation costs

Accretion expense

December 31, 2019

Change in estimated reclamation costs

Accretion expense

December 31, 2020

Change in estimated reclamation costs

Accretion expense

December 31, 2021

The restricted cash discussed in note 6 relates to the surety bonds provided to the governmental agencies for these and other reclamation obligations.