Vagueness in software requirements documents can lead to several maintenance problems, especially when the customer and development team do not share the same language. Currently, companies rely on human translators to maintain communication and limit vagueness by translating the requirement documents by hand. In this paper, we describe two approaches that automatically identify vagueness in requirements documents in a multilingual environment. We perform two studies for calibration purposes under strict industrial limitations, and describe the tool that we ultimately deploy. In the first study, six participants, two native Portuguese speakers and four native Spanish speakers, evaluated both approaches. Then, we conducted a field study to test the performance of the best approach in real-world environments at two companies. We describe several lessons learned for research and industrial deployment.