I completed my MSc in Environment (H&S strand) a couple of years ago but I guess some of the bullets I can recall from my business case might help:

1. To update my knowledge of HS and E legislation
2. To improve my ability to research topics and identify solutions
3. To improve my strategic focus
4. To prepare me for a more senior role
5. To reduce the business's reliance on outside consultants

I also showed a comparison of course costs from different providers and how the distance learning course I chose minimised my absence from work.

On reflection I think the course only achieved some of these but it certainly stretched me and altered my thinking

Hope that helps a bit