Need an environmental impact statment or field survey or other specialized service and you don't have staff to do it - hire a consultant. Here are some examples of the types of private sector groups that might employ environmental people. Starting pays for B.S. people can be very good. If you prove your worth to a company, salary can go up much more than it can working for government. This is especially true for some national consulting companies.
Good work brings in good business.
The down side for some may be travel and the long hours when required. If you are very good, the experience is exhilarating. Not many positions, hard to find, but you're on the front line. Graduate school is a good place to be if you really NEED to do research and learn new things. You can increase your marketability with a master's degree.