It pretty much washes right off. Another option..get rid of the silver cover. 3rd option...buy a new bumper.
2013 Jeep Wrangler Unlimited Sahara
AEV Pintlers, front and rear bumpers, tire carrier
AEV 3.5 RS lift, synergy ball joints
4.56 gears and eaton lockers
Micky Thompson 35" MTZs
JW Speaker 8700s and 6145s and Recon LED Tail Lights
Trek Armor Seat Covers