Complex sentence: This would be used in BEPO, the experimental reactor built at Harwell, but the plant required uranium oxide feed, and the export of this from the United States was banned under the McMahon Act.
Split into simpler sentences: This would be used in BEPO, the experimental reactor built at Harwell. Unfortunately, the plant required uranium oxide feed, and the export of this from the United States was banned under the McMahon Act.