I'm checking this out right now. So far I've hit a roadblock. Most of its explanation for the dangers of chemtrails comes from one interview with Dr Horowitz. Looking into him he seems like the type of guy to ask but he provides no proof or even a date for his claim that ETHYLENE DIBROMIDE is in the jet fuel. Now, he could have gotten that information from the EPA before it was removed from jet fuel since he doesn't mention when he started looking into contrails.

ETHYLENE DIBROMIDE was once in jet fuel and even standard gasoline but since has been removed for health reasons. I cannot find any other evidence that it's being used currently or that it's been found in our air recently.

The rest of the site builds on that ONCE SENTENCE or Horowitz, that didn't provide any facts other than "the EPA said" on an undisclosed date, and runs with it. All further evidence of it's existence in our air come from pictures with rainbow effects. Anyone can produce those pictures so we cannot take that as evidence. I live in a major city and watch the sky constantly and I've never seen such a thing [unless it just rained and its a normal rainbow].

Lots of facts on that site but they are presented poorly. Most of the evidence is weak. Still, it is an excellent place for someone to start with and actually build a solid case for chemtrails, assuming there is one.