

The Silicon Valley Toxic Waste Heat Map - thinkcomp
http://www.plainsite.org/environment

======
uvdiv
What's the interpretation of comparing a contaminant level in a monitoring
well (in the soil?) with a standard meant for drinking water?

The "total reading" statistic is a bit useless. 5 ug/L here, 10 ug/L there,
does NOT make 15 ug/L total.

~~~
thinkcomp
My understanding is that the monitoring wells measure groundwater so the
drinking water standards are relevant.

Yeah, the total is just there because I thought it would be better to make the
data visible than not. Overall it's pretty meaningless but it might help in
some narrow instances where you're looking at one small area versus another
small area in the same timeframe. Sometimes the wells are very close together
and different colored icons get overlaid so it's not clear from the map that
numbers are even that high.

~~~
uvdiv
You're the author? I think you have a parsing issue. I'm looking at barium:
apparently the color-coding only looks at the number, discarding the unit (ug
vs. mg). The MCL is 1 mg/L; for a measurement of "514 ug/L" (=0.514 mg/L), you
code it as >100x Federal Threshold:

<http://i.imgur.com/Vd75wlo.png>

And for more confirmation, on the sidebar, the 0.220 mg/L measurement maps to
the minimum of "0.220" (out of the 2 measurements in the field of view), and
the 514 ug/L maps to the maximum "514.000". They should be 0.220 and 0.514
(mg/L).

Your map shows severe Barium pollution over the whole region, but that's just
this error repeated many times.

<http://i.imgur.com/bDQ3Lie.png>

update: And zinc too. The severe zinc pollution all over the map is also an
error:

<http://i.imgur.com/8RoXpy8.jpg>

update: Copper too:

<http://i.imgur.com/ZZsm02G.jpg>

~~~
thinkcomp
Good catch. Thanks!

------
randallu
The CA map is interesting too, because it has the cleanup sites with some
information on them:
[http://geotracker.waterboards.ca.gov/map/default.asp?global_...](http://geotracker.waterboards.ca.gov/map/default.asp?global_id=&senate=&assembly=&x=-122.13380809170839&y=37.433736657802115&zl=15&ms=640,480&mt=roadmap&geotracker_luft=true&geotracker_slic=true&geotracker_landfill=true&geotracker_dod=false&wdr=false&geotracker_ust=false&dtsc_cleanup=false&dtsc_permit=false&showdist=false&searchdist=1000&searchaddr=500%20california%20ave,%20palo%20alto,%20ca)

It seems like gas stations typically leak a lot of gasoline into the ground.
Is the burden always on the taxpayer to clean up?

~~~
davidandgoliath
Quite interesting. I would imagine just because of the fact that gas stations
are so common & plentiful, they're going to be one of the more common items on
that cleanup list.

That, and they're probably fairly easy targets for audits vs. the average co.
given the nature of their business (Joe Blow could leak oil into the water for
awhile without getting caught, a gas station probably has frequent checks). As
for the burden on the tax payer: I don't think any of those are cleanups, just
simply gas stations fixing underground leaking tanks. They all appear to be
"Leaking Underground Tank (LUST)" cases.

The health burden is upon us all though.

------
jpdoctor
Fairly well centered on Wilson Sonsini? I'm trying not to confuse correlation
with causation here.

------
pairing
So how close to one of these indicators do I have to be for it to be
hazardous? There's two hot spots very close to my apartment complex (<1000
feet). Now I'm paranoid since I've been living here for 2 years and drinking
tap water.

Edit: Zooming out on the south bay it looks like the whole area has issues. I
thought the TCE issue was contained to the Moffet Field area. It will be
interesting to see the whole bay area when you add other counties. It's
amazing to me that these hazardous conditions don't affect home prices.

------
lifeformed
The presentation of data here seems misleading. The red-green glow around each
point seems like it's showing some sort of range of toxicity or something,
that anything in the glow is affected somehow. But it's actually just a
highlight around the icon. If you zoom in, the glow stays the same relative to
the icon, but the range on the map is greatly reduced. If you zoom all the way
out, it looks like the whole place in in a red zone, but it's not that way if
you zoom in.

------
rdl
Is the data just for Santa Clara County (and really, those specific areas), or
are they really that concentrated? Seems hard to believe there are no sites in
the rest of the Bay Area.

~~~
thinkcomp
So far I've only had time to test it out with Santa Clara County. I have all
of CA's data but since it's >10GB I'm going to do some optimization and
testing first to avoid killing my server.

~~~
rdl
I wish there were a way to overlay it on Craigslist listings, redfin, etc.

------
dmourati
So, I work in one of these zones near Moffet Field. What do I do?

~~~
Tichy
Wear a protection suit to work

------
polarix
To me this kind of makes the earlier article seem overblown. Okay, so the
entirety of silicon valley is a toxic waste dump? Well then.

~~~
digisign
Zoom out.

~~~
cmccabe
He didn't enter the data for the other regions yet.

