Login or register (free and only takes a few minutes) to participate in this question.
You will also have access to many other tools and opportunities designed for those who have language-related jobs (or are passionate about them). Participation is free and the site has a strict confidentiality policy.
Under the environment headline on this site, you will find various reliable glossaries and dictionaries on the subject.
All are in English, some are multi-lingual too. Due to a useless internet connection tonight I could not log onto some of them and therefore will let you make up your mind as to which you like best in regards to the document you are translating.
Explanation: I recently had a major translation on hazardous materials and waste management - I used too many sources for the hazardous materials terminology to be able to list them all here, but found the following good linke for waste management, which also contains environmental terminology.