Emergency Plan For a Agricultural Warehouse Fire

I am currently doing a Toxicology assignment and was hoping that someone could shed light on how different organization would attack this particular incident. The situation involves a chemical fire near a small town. I am contacting you because I am hoping to utilize your professional skills. The assignment is as follows.

THE PROBLEM:
There has been a warehouse fire and the warehouse, located in rural area, contained 6 million kg of agricultural chemicals. The warehouse had a "secret" floor drain that was piped with a 20 cm pipe to small lagoon. The lagoon is located so that the overflow water from the lagoon conveniently flows to the highway ditch and that slopes down for 0.8 km to a creek. The ditch connects with the creek about 10 km above where the creek joins a major river. A huge amount of water was used to fight this fire and it was pumped from the creek. Some of the water sprayed on the fire was channeled via the floor drain in the warehouse to and 20 cm pipe to a lagoon, and from the lagoon the water flowed into the ditch and subsequently into the creek. In the dark of night, black sooty smoke and excitement of the fire fighting effort, no one notices that dirty foamy water was flowing from the lagoon into the ditch and down the ditch to the creek. Upon discovery, the local fire chief called the Dept of Environment and dispatched a bulldozer to dam the creek about 4 km from the river, dam the roadside ditch and increase the sides of the lagoon. Because the soil was disturbed around the lagoon, its wall broke and the water rushed into the ditch. However, the ditch dam held. The bulldozer operator was ordered to construct another dam because the demise of the first ditch dam was eminent. A small "dugout" was constructed beside the lagoon and the lagoon drained into the lagoon. It was noted that the "dugout" was filling with water before it started receiving water from the lagoon. In the phone call you were informed that the creek water was backing up fast and will wash out the temporary dam. Rain was not in the short-term weather forecast that the pilot obtained during the flight.

The assignment requires me to anticipate how various organizations would be involved in attacking the situation. I have contacted a few rural areas to discuss their emergency plans. Yet I am having difficulty in piecing together the puzzle. For example, how would the fire dept., law enforcement, toxicologists, regional environmental organizations, and the warehouse it-self, be involved- what other organizations am I forgetting? How would they each participate in remedying the incident?

Again I thank you for your time and effort.