[quote author="MojoJD" date=1256780072][quote author="JVNA" date=1256639688][quote author="GoIllini" date=1256619909][quote author="SoCal78" date=1256614374][quote author="bkshopr" date=1256613418]The site was graded and top <span style="color: blue;">10'-15'</span> soil was replaced and imported with new earth before construction.</blockquote>
The first article says the contamination is 20'-25' below ground. So I'd wonder what, if anything, is accomplished by replacing the soil only ten feet above that... is it just so they can "say" they did something?</blockquote>
For benzene to be a risk, you have to either breath it, eat it, drink it, or be exposed to it on your skin. You don't drink the groundwater, so that pathway is eliminated. The clean soil on top of the site eliminates many of the other pathways. Benzene is biodegradable, especially when oxygen is present. So, benzene that is in soil vapor will readily be destroyed by soil bacteria before it migrates through a 10 foot soil column.
<strong>That is one of the differences between benzene and TCE (trichloroethylene), which was the primary volatile organic chemical (VOC) that was present at the base... TCE does not degrade as quickly, so it can migrate through the soil and potentially enter a home at the surface.</strong> And yes, I do find it ironic that VOCs (Volatile Organic Chemicals) are an issue at VOC (Villiage of Columbus).</blockquote>
So in your opinion, VOC residents are at risk for TCE exposure and harm?
BTW, I like these types of discussions. I know it angers some, but I like knowing the potential harm in Irvine and surrounding areas. If there is harmful chemicals, I'm sure it isn't isolated to just Tustin.</blockquote>
You mean like the much more prevalent and widespead mess under south/west irvine? Check into the TCE from El Toro that moved under woodbridge and surrounding neighborhoods. the Tustin situation is actively managed and has monitoring and cleaning efforts underway.
And in a different thread, I found some stats on the fridge filters that came with the GE fridges for the Camden home owners.
<a href="http://www.waterfiltercomparisons.com/water_filter_comparison.php">filter comparison chart</a>
99% removal of benzene and TCE. not bad - considering the drinking water comes from other, non-contaminated areas anyway.</blockquote>
I don't quite know what to make of that filter comparison chart. There are chemicals listed that should be removed by any decent reverse osmosis unit or activated carbon filter. But, for example, the chart shows that the Brita filter I use (activated carbon) isn't good for removal of many organics (Benzene
and other VOCs). But that doesn't make any sense. Carbon filters are very good at removing these chemicals. The organics prefer to be attached to a carbon media rather than stay dissolved in water. So as water passes through the filter, the chemicals attach to the carbon, until the filter is saturated and can't hold any more. An RO unit uses a different approach; it is basically a very, very fine screen. Tiny water molecules can pass through. Bigger molecules, like benzene, have a lot more trouble and are held back. Why the table shows that one brand of device works, while another using the same technology does not is puzzling. It may be that the manufacturer did not subject his device to the specific testing protocol required for this report.
I use the filter because it improves the taste of the water, not because I am worried about chemical contamination. My morning tea tastes better! IRWD does a good job of providing safe water. So I'll stick with what I've got.
