US Oil Sands Inc. announced the filing of its 2011 independent resource evaluation report. The company engaged Calgary-based Sproule US Limited to complete an independent resource evaluation report dated March 13, 2012 in compliance with National Instrument 51-101 - Standards of Disclosure for Oil and Gas Activities. The evaluation results detail the bitumen resource assessment of the company's PR Spring property in Utah as of February 29, 2012, and incorporate the results of the 145 wells drilled and cored on the Company's PR Spring development block in 2011. The independent Sproule estimate of 189.8 million barrels is up from the company's prior year audited estimate of 177.8 million barrels . US Oil Sands' PR Spring property lies within the PR Spring Tar Sand Deposit and consists of four leases that encompass 5,930 acres. The Company also holds leases on an additional 26,075 acres that have not been evaluated in the Sproule Report. US Oil Sands currently holds 100% working interest in its Utah-based assets. The reporting of discovered resources as the high level of classification at this time reflects the status of the resource estimates as interim results of an ongoing engineering and economic evaluation of the property, the disclosure of which has been necessitated by timing considerations related to annual filing requirements. The in-place volumes within the current mine plan areas have been classified as discovered resources, based on core hole data, assays, test pit results, outcrop data and geological mapping. Although it is not possible to identify either the exploitable portion of the discovered resources or the recoverable portion of those resources until the final mine plan is incorporated into the geological model, Sproule is confident that contingent resources will be assigned to the three proposed and permitted mine pits once this has been done. Since that work is expected to immediately follow this assessment, we believe the most specific classification, as of the effective date of this report, is discovered resources. Discovered resources were also estimated for the balance of the property, using information gathered from exploration core holes drilled on a nominal 40-acre spacing, supplemented by historical core assays, outcrop data and geological mapping. Although the current geological data clearly supports the expectation that at least a portion of the area will be mineable, and it would be possible to define conceptual mine plans for that area, it is Sproule's opinion that recoverable volumes cannot be assigned until a mine plan has been defined and that definition of a mine plan requires that the Company gather sufficient additional core hole data to map the ore beds to the same degree as the current mine plan area in order to identify the exploitable portion of the resource. In addition, the planned economic evaluation of the currently proposed mine pits will assist greatly in the further classification of these resources. Thus, Sproule believes that contingent resources will be assigned to a portion of the area once the additional information is available and, as a result, it is the opinion that the most specific classification, as of the effective date of this report, is discovered resources. Until a forthcoming economic evaluation is completed, there is no certainty that it will be commercially viable to produce any portion of these resources.