Check with your version of your state's Department of Natural Resources. Carp are bottom feeders, and thus pick up more than their fair share of pollutants in the waterways. I know that here in MI, it is suggested that not more than a couple servings a month is safe due to pollution.
Post-SHTF, you gotta do what you gotta do, and your liver will just have to deal with it. Now, while you have resources and choices, it may be unwise to consume it in quantity in your area.