that was true 10-15 years ago. but today, pollution payback, which includes mining, is only 2 years. 1 smokestack is cleaner than 10,000 tailpipes. the grid is getting cleaner all the time, old dirty power is being retired, wind/solar and storage are coming online. nuclear can't survive without government insurance because private insurers won't cover them. hence they are the most expensive subsidized source while solar is now the cheapest. battery prices are also falling and will be at parity with gas cars in a year or 2. you can see what your state is doing on electricitymap.org