Ammonia leak at a chem plant

I have an idea for a mission type since these do happen from time to time perhaps there should be an ammonia leak at a chem plant call for that you would need 1 mobile command vehicle 3 HazMat units 1 mobile air unit 5 patrol cars for crowd control reasons 1 ambulance bus 4 heavy rescue vehicles please let me know what you think it should look like thishttp://www.processingmagazine.com/ammonia-gas-leak-injures-10-workers-at-texas-chemical-plant/