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RECLAMATION OBLIGATIONS (Details) $ in Thousands |  | 12 Months Ended
--- | --- | ---
Oct. 03, 2015 USD ($) | Dec. 31, 2016 USD ($) property | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($)
Mineral Property Interests |  |  |  |
Number of most significant properties subject to reclamation obligations | property |  | 2 |  |
Surety bonds upfront deposit amount |  | $ 500 |  |
Reclamation obligations |  |  |  |
Reclamation Adjustment |  | 89 |  |
Reclamation Accretion |  | 506 | $ 429 | $ 407
Reclamation and remediation expense |  | 595 | 429 | 407
Changes in the asset retirement obligations |  |  |  |
Asset retirement obligation liability, beginning balance |  | 7,784 | 7,471 |
Settlements |  | (66) |  |
Accretion of liability |  | 506 | 429 | 407
Adjustment reflecting updated estimates |  | 1,619 | (116) |
Asset retirement obligation liability, ending balance |  | 9,843 | 7,784 | $ 7,471
Current portion |  | (537) | (215) |
Non-current portion |  | 9,306 | 7,569 |
Asset Retirement Obligation Assumptions |  |  |  |
Undiscounted Cash Flows |  | $ 10,700 | $ 9,500 |
Minimum |  |  |  |
Asset Retirement Obligation Assumptions |  |  |  |
Remediation timeline |  | 2017 | 2016 |
Inflation rate (as a percent) |  | 1.60% | 1.40% |
Tonkin Complex |  |  |  |
Mineral Property Interests |  |  |  |
Surety bonds upfront deposit amount | $ 3,600 |  |  |

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