As a biomedical engineering graduate student, I would say one in this field would need both skills (interpersonal skills and technical skills) in a ratio of 50:50. Although I agreed in an earlier reply that “interpersonal skills are more essential to the work environment especially to teamwork oriented place than technical skills”. I still emphasize that one cannot think about having either skill as an option and expect to be a successful engineer in the future. Ignoring one part of these required skills or not paying the attention to it would lead to difficulties later on as it would affect the engineer performance as well as the career. When it comes to finding a job, this is what HR employer mostly would focus on when interviewing any engineer either for an internship or for a job. It is not only a matter of having the technical skills in a particular discipline, but it is also about the capability to manage responsibilities and perform well in all situations with any kind of people by employing the right interpersonal skills.
However, one can learn and practice technical skills, but it is hard to learn interpersonal skills.