Cachers/Backpackers in the Sierra Nevadas: Caution

[+Twitch Hugs Trees]

I don't want to come across as a crazy alarmist, but I do feel like this should be brought to the attention of our geocaching/hiking community. If this belongs in the regional forums, my apologies.

 

Today the Sierra Fund released the results of the Gold Country Recreational Trails and Abandoned Mines Assessment, identifying specific recreation areas around Downieville, Nevada City and Foresthill where popular trails intersect with known abandoned mine sites. In these areas, scientists collected samples to analyze whether the public could be exposed to hazardous substances. Contaminants of concern include heavy metals such as lead and arsenic, and also other hazardous materials, including asbestos.

 

At certain locations, toxins were found at levels that could affect human health:

* In the Nevada City area, arsenic was found at levels of concern on Banner Mountain trails, and asbestos in one location on the Newtown Ditch trail used for biking and hiking.

* At the Foresthill OHV Area in and around the abandoned Marrall Chrome Mine pit, samples showed up to 40% asbestos and off-the-charts levels of lead in the soil on trails where families ride OHVs.

* In the Downieville area, certain biking, hiking and OHV trail locations tested high for arsenic, lead and asbestos.

 

Here is a link to the release: Link

 

I realize that information is still being collected and analyzed, but to me an ounce of prevention is worth a pound of cure-- geocachers/hikers/backpackers should be made aware of the possibility of exposure. I hope this helps.

[mtbikernate]

Certain bedrock layers in my area have 4x the "global mean" concentrations of arsenic. These layers of bedrock are exposed all over the place...in public parks, navigable waterways, road cuts, etc. It happens.

 

There's an asbestos outcrop a bit north of me, too.

 

Spend some time in Utah and other places where uranium was mined. THAT is some nasty mine drainage.

 

Your post is rather alarmist. It's good to be aware of these natural deposits of toxic substances, but no sense getting worked up over it. This stuff is more common than you might think, and some things (like the asbestos) isn't so harmful in its bedrock matrix.

[+dreamarcher]

This is exciting. I'm definitely going to these places.

 

In all seriousness, you can't be harmed by this stuff unless you somehow ingest it or maybe if you build a house on top of it and live there for 30 years.

[+Touchstone]

This is exciting. I'm definitely going to these places.

 

In all seriousness, you can't be harmed by this stuff unless you somehow ingest it or maybe if you build a house on top of it and live there for 30 years.

 

You could even Waymark the spots if you like

 

Super Fund Sites

[+dreamarcher]

Ish. Alviso, Ca. Local bay area residence have always joked about having to live there or how bad it is to live there because it's always been a dump. Plus the natural stinkiness of the bay always ended up on the south shore at Alviso. As a kid we used to go out to the Alviso ghost town (old hunting lodge) and tromp around in the mud and gunk. Probably why one of my kids is disabled. -sigh-

[mtbikernate]

This is exciting. I'm definitely going to these places.

 

In all seriousness, you can't be harmed by this stuff unless you somehow ingest it or maybe if you build a house on top of it and live there for 30 years.

 

You could even Waymark the spots if you like

 

Super Fund Sites

 

I thumbed through those and unfortunately, not all of those sites are ACTUAL Superfund sites as defined by CERCLA.

 

I will agree with your statement with a caveat...there needs to be a route of exposure. Ingestion is only one potential route of exposure. You can inhale it, and simple skin contact can be another. Inhalation is actually the most significant route of exposure.

 

There may be plenty of toxins out there, but they're only hazardous if there's a route of exposure.

 

This stuff's out there...but ARE people being exposed to the substances in the first place? If so...how?

[+AndrewRJ]

This is exciting. I'm definitely going to these places.

 

In all seriousness, you can't be harmed by this stuff unless you somehow ingest it or maybe if you build a house on top of it and live there for 30 years.

 

It really isn't all that hard to ingest it. If contaminats occure in ORV and mountain biking areas like the results show, any dust that you breath will likely contain some amount of heavy metals, and I am not even talking large obvious dust clouds, anything in the air.

 

That said I don't believe that you are going to be in an area generally long enough to have an exposure problem, but it is a lot easier to be exposed then you might think.

 

I know on a river here in Washington that drains an old gold mining area that has been declared a superfund site and they used spray tackifier to keep the surface soil from eroding in wind. Still wouldn't drink from the river even with my fancy water filter.

[mtbikernate]

then you better not go to most places in the southwest. Lots of radiation from old mining and weapons testing.

[+TotemLake]

then you better not go to most places in the southwest. Lots of radiation from old mining and weapons testing.

I think the point is as long as urban myths exist and are commonly believed rather than the truth being put out there on how easy ingestion can be accomplished, nothing will be done about the polluted sites.

 

Take for instance all of the radiation from old mining and weapons testing in the southwest.

[mtbikernate]

I'm working on a master's degree in environmental science...I'm not exactly going to be putting faith in urban myths about exposures to hazardous substances.

 

Exposures are measured in time-weighted-averages.

 

How long are you exposed to the stuff when you're out on the trails? Not long. An absolute exposure at a given point in time may be high, but averaging it over times when you're not exposed at all...really drives the average down.

 

It's a different story for folks who work in the those areas with exposures lasting several hours in a day.