29.03.2013 Views

summer 11 / 24:2 - Grand Canyon River Guides

summer 11 / 24:2 - Grand Canyon River Guides

summer 11 / 24:2 - Grand Canyon River Guides

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

WitH fundinG avaiLabLe through the American<br />

Recovery and Reinvestment Act of<br />

2009 (arra), <strong>Grand</strong> <strong>Canyon</strong> National Park<br />

completed projects at several Abandoned Mine Lands<br />

(amL) sites to improve human safety. Old mine sites<br />

are potentially hazardous to park visitors and should<br />

never be entered. The projects eliminated human<br />

access to five abandoned mines, while maintaining<br />

protected habitat for wildlife and preserving the sites’<br />

historic character. An Environmental Assessment was<br />

completed in February 2010 which identified the hazards<br />

associated with amL features and proposed proper<br />

closure techniques and designs. The projects at <strong>Grand</strong><br />

<strong>Canyon</strong> were completed at the end of November 2010.<br />

Eight amL features at five sites were closed by constructing<br />

bat-accessible gates and cupolas (domes),<br />

and using polyurethane foam plugs along with dirt<br />

backfilling. All five sites are located in the backcountry<br />

and accessible to river and backpacking users.<br />

• Bass Copper Mine: A bat-accessible gate was installed<br />

to protect bat habitat.<br />

• Pinto Mine: A bat gate and a bat cupola were installed<br />

at an adit and shaft, respectively.<br />

• Tanner-McCormick Mine: A bat gate was installed<br />

to protect habitat and to exclude visitors from areas<br />

of poor air quality such as low oxygen levels in the<br />

mine.<br />

• Copper Grant Mine: A bat gate was installed to<br />

protect habitat and to exclude visitors from the<br />

mine, which has rotting support timbers.<br />

• <strong>Grand</strong>view Mine: Three shallow adits or prospect<br />

pits were plugged and backfilled.<br />

WiLdLife Habitat at CLosure sites<br />

Abandoned mines often provide habitat for wildlife,<br />

including rare and sensitive species. Bats, among the<br />

world’s most beneficial but vulnerable mammals, use<br />

mines for roosting, rearing their young, hibernation,<br />

and for crucial rest stops during seasonal migrations.<br />

Interpretive signage indicating protected habitat was<br />

placed at the sites. Wildlife monitoring at the sites<br />

that provide habitat for sensitive species will continue<br />

through 2012.<br />

page 12<br />

Closure of Abandoned Mine Lands<br />

In <strong>Grand</strong> <strong>Canyon</strong> National Park<br />

stay out and stay aLive<br />

Old mine sites are inherently dangerous. They were<br />

designed to last only long enough to extract ore. They<br />

were often developed along unstable faults, and drilling<br />

and blasting further destabilized the rock. Timbers,<br />

support beams, and rock bolts were left to rot and decay,<br />

and may now be structurally unsound. The effects<br />

of temperature, air, and water further cause mines to<br />

become unsafe.<br />

Lethal concentrations of gases such as carbon<br />

monoxide, carbon dioxide, and hydrogen sulfide can<br />

accumulate in mines. Pockets of still air with little<br />

or no oxygen also exist. Areas of bad air in mines are<br />

commonly odorless; people can succumb to the effects<br />

of oxygen deprivation or poisonous gases with little<br />

warning.<br />

Deanna Greco<br />

pHysiCaL sCienCes proGram manaGer<br />

for <strong>Grand</strong> <strong>Canyon</strong> nationaL park<br />

Announcements<br />

Lost:<br />

A pair of regular prescription glasses was lost at 186<br />

mile camp (<strong>River</strong> right) on May 8th. They are in a<br />

hard grey case with either “Ocean Pacific” or “Carrera”<br />

on the case (couldn’t remember which). If found,<br />

please contact: Walt McGourty at w.mcgourty@<br />

comcast.net<br />

FOUND:<br />

A black rubber bag (approximately 18” x <strong>24</strong>”) with<br />

identification and Outdoors Unlimited cup inside was<br />

lost on April 21st at South <strong>Canyon</strong>, Mile 30, at upper<br />

part of lower main camp. Please contact either Burton<br />

Vanderbilt at bvanderbilt@msn.com or Outdoors<br />

Unlimited at (800) 637-raft.<br />

grand canyon river guides

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!