[Curious]

I am a lay person.  Traveling with my children and their friend back from a shopping trip at about 7pm on 6/19/07.  Windows closed, air conditioner on.  All of a sudden, the cab of the truck is filled with an intense chemical smell.  I tell the girls to hold their breath. ( I had this happen to me once before in the winter at the same location) 

We traveled approx. one tenth mile further down the road and I opened the windows.  Kids breathed in the fresh air.  I asked what it smelled like to them.  They immediately said nail polish. I thought nail polish remover.

The spot where it happened is right between a beverage plant and its water treatment facility.  I checked with a friend and was told it was probably acetone or toulene in gas form. 

My question is how many gallons of the liquid form of either would it take to give off that much gas?  Traffic was flowing at 45mph. Beautiful day, light breeze. 

[Borek]

No way it can be answered, not enough data.

[Curious]

What data would I need to supply?  Number of treatment ponds?  Distance of ponds from road?  That must be many gallons of chemical to give off that much gas, yes?

[Borek]

First thing is that it is not possible to say how much gas was present in the air, no matter how much other data you will give. That's the basic information, but you can't supply it without proper equipment. Looks to me like your question can't be answered.

[Curious]

Borek, thank you for your assistance.  I do have the distance of the ponds from the road and the size of the ponds.

What I am really interested in is the amount of liquid acetone that would be needed to create such a strong smell. (700" away) 

Would you be able to send me in the direction of someone who may help me further?

[Borek]

such a strong smell

This phrase doesn't tell anything about the gas concentration, it is like asking "how much sugar yoiu have to add to water so that it is THAT sweet".

Smell is not a tool to be used in quantitative analysis. With some luck you may be able to find something like odor detection limit - which means the lowest concentration of substance than can be detected by smell, but I suppose that level was exceeded, perhaps even many times.

No idea where to look further. Some Googling may help.

[Curious]

Ah, thank you.  I understand now.  I will try environmental air quality or DEC next.

[Mitch]

Most definitely acetone from the sound of it.

[kiwi]

well its back-of-the-envelope time:

(a) assuming acetone was at its odour threshold (~150 ppm)
(b) assuming the pond was 200 m away
(c) assuming no acetone remains unvolatilised
(c) in a complete bastardisation of everything we know about air density, wind and diffusion, assuming the concentration of acetone is even over a hemisphere centred over the pond, with its outer edge at the observer

So volume of a sphere is 4/3.pi.r^3, which gives our volume of the hemisphere as 16.74 x10^6 cubic metres; which means there is 16.74 x10^3 L of space inside the hemisphere. So if all of the air inside that space is at 150 ppm of acetone, then there is 2511 litres of gaseous acetone in that space. From the ideal gas law we know the volume of a gas is 22.4 L/mol, so there is 112 moles of acetone in the hemisphere, or about 6.5 kg (or about 8.2 L).
Note the reliance on a series of estimates and approximations - some of them quite major. This number is not to be taken as gospel, but its an estimate. And it shows that comparatively little acetone is required to produce a smell over a wide area.

[Curious]

kiwi -- I like your thinking,  thank you.  I got the run around from the Environmental Air Quality Office. The person I spoke with actually does the annual checks for this facility.  He did not sound very interested.

There are:

(4) 100' diameter treatment ponds*
(2) 300'x150' ponds* - these are the nearest to the road, approx. 700'
(2) 200'x125' ponds*

*all dimensions are estimated via satalite images

Again I thank you.  Your post has been most helpful.

[Borek]

Depending on circumstances amount of the acetone involved can easily differ by orders of magnitude. Please don't treat numbers given by kiwi too seriously, they are just as good as 1 kg or 1 tonne.