This document provides information about a textbook on environmental engineering. It notes that the textbook covers the curriculum for bachelor's and master's degrees in environmental engineering at Nepalese universities. It is also based on Nepalese environmental protection acts and regulations. The textbook is intended to help with exams for engineering licenses and other national and international environmental exams. Brief biographies are provided for the two authors, Er. Dinesh Prasad Bhatt and Er. Basant Lekhak, who have experience teaching environmental engineering subjects.