Ok... here's what I have first hand about Republican administrations.

I have a friend who has been at EPA since 1974...he spent 'most' of that time near the top... in various positions...the last 10 years or so as a GS-15 supervisor and acting or asst. head of a department. He told me years ago that when Reagan came in, he did exactly what the had threatened promised...he dismantled technical programs that had taken years to create, and sent top-notch scientific reseachers packing. When Clinton was elected, attempts to rebuild were awkward, as experts were 'elsewhere'.
Once G.W. Bush was in, it got worse. Serious 'protecting of the environment' was a joke, as all the policy positions were stuffed with bought & paid for industry apologists. My friend's precise comment..."I've never seen anything like it in my 25 years." He was told when certain issues came up that he had expertise on...'We don't need your input on that... policy has already been decided.'...This told to a GS-15 with 20+ years experience.
Regulations were gutted, studies were shelved, entire work groups were paid to do NOTHING, while PR wonks were making excuses and taking advice from the chemical industry, the oil industry, the pesticide industry, the logging industry, the mining industry...and anyone else with a vested interest in seeing little or no oversight on environmental problems.

THAT is part... a small part... of what one could expect in another administration where Republicans either set policy or block good policy.

Be very afraid.

Oh... my friend is retiring this Summer.