AMHERST, Mass. – A plan for an enterprise that would monitor and provide failure warning systems for earthen structures has won the $45,000 phase of the Technology Innovation Challenge, a competition for the best entrepreneurial technology business plan run by the College of Engineering, the Isenberg School of Management, and the College of Natural Sciences and Mathematics at the University of Massachusetts Amherst. The challenge, a competition for students, recent alumni and faculty advisors on campus, is primarily sponsored by Wolf, Greenfield & Sacks, a Boston-based law firm specializing in intellectual property.