Specifications include, but are not limited to: A. The contractor and subcontractor will give preference in employment opportunities under this Agreement to qualified Indian applicants who can perform the work required regardless of race, color, creed, age, sex, religion, national origin, disability, or tribal affiliation to the extent set out in the paragraphs below. B. The contractor and subcontractor will not use pre-employment standards, qualifications, criteria, or other personnel requirements as barriers to Indian employment except when such criteria or standards are required by business necessity. The contractor and subcontractor have the burden of showing that such criteria or standards are required by business necessity. C. The contractor and subcontractor agree that Indians will be given preference for at least seventy percent (70%) of the project work force provided that sufficient qualified Indian applicants are available. The phrase “work force” will not include “core crew employees”.