Hmm, well, not all pretroleum based products float. Some are miscible, and some of the distillates can actually be more dense, especially those that are emulsified with mineral components. As for VOCs, not all of which are petroleum based either, there are several methods depending on what compounds are present. Some VOCs are readily biodegraded, some can be captured by charcoal filtration beds, others have to be cooked off or decomposed ionically (UV, Ozone, even microwave). Recent EPA mandates are going to drive water treatment systems here in Florida and elsewhere into developing new treatment plants using UV (as with the Cat/Del UV system for treating 90% of metro New York's water supply) or Ozone, which is currently being recommended as the next primary treatment system here in Central Florida, to replace Chlorination as the primary treatment method in order to reduce the number of Chlorinated by products of treatment. Most treatment systems are targeted at either capture or neutralization or a combination of those processes, so with UV, ozone or chemical reaction to decompose those VOC compounds along with active charcoal beds and flocculants to capture the contaminants. If the molecular compound is weak enough that UV radiation can break down the bonds, then that is generally going to be probably the cheapest method, as the energy and storage requirements seem most economical of all the current proposed methods acceptable to the EPA.

Some of those industrial chemical compounds are pretty scary. In high school I remember we had to evacuate the chem lab because a vial of picric acid had started to crystallize. The same thing happened out at a Hanford lab in Central Washington and they ended up setting off the emergency sirens along the river corridor evacuating a lot of people in the area. That place can be downright scary at times, there's so much crap out there, and the state's only Extemely hazardous waste facility is right out there next to probably the biggest repository of radioactive cesium and strontium in the world.

As for the MMH and the N2O4, unless you are talking a massive release, I would expect that they would react out in the environment fairly quickly, so the biggest concern would be containment first, and removal if practical or in the interest of public health, but not if in a fairly isolated location necessarily. I believe you meant to say mono-methyl hydrazine, which is a rocket fuel component. Monel is a type of semi exotic stainless steel that I don't think you can get into solution with hydrazine in any form very easily, and not with any real industrial purpose I can find. But I am no rocket scientist either. In any case, methyl hydrazines pose a serious health risk, and if I were looking to remediate a spill, I would prefer to react it out if I had to get rid of or neutralize it quickly, rather than try and capture it. You should be able to reduce it to ammoniated salts fairly easily. N2O4 will react with the water to form nitric and nitrous acids, which will decompose further into nitrates following reaction to suspended solids and colloidal contact. If I had to react it out, I'd find some clay with a generous amount of colloidal constituents (cat litter?) and distribute that to the spill site. It should be easy then to disperse the nitrate products or collect them up as precipitates. I'd research it more, but off the cuff that is my first impression. For emergency response I'd be at level A suits and SCBA most likely, treat it like I would an iso-cyanate release (because of the volatility of the MMH) or methylene chloride spill(because of the acute exposure reaction).


I remember well when the Kerr-McGee plant blew up outside of Vegas. Weren't they also working with rocket fuel? Man, what an explosion!