Dear Rahul,
You can check the top colleges for M.tech for environmental engineering in Karnataka below
National Institute of Technology Karnataka Surathkal
Manipal Institute of Technology, Manipal
Indian Institute of Science, Bangalore
PES University, Bangalore
BMS College of Engineering, Bangalore
JSS Science and Technology University, Mysuru
To check the complete list you can refer below link
https://engineering.careers360.com/colleges/list-of-engineering-colleges-in-India?f%5B0%5D=sm_college_course_level%3APG&f%5B1%5D=sm_college_degree%3AM.E%20/Mtech.&f%5B2%5D=sm_college_state%3AKarnataka&f%5B3%5D=sm_course_offered%3AEnvironmental%20Engineering
Good Luck!!
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