Shenandoah National Park will be hiring four biological technicians for the summer of 2012 to assist with fish and benthic macroinvertebrate monitoring.  The actual job announcement (including how to apply and minimum qualifications) is currently posted on USAJOBS
http://www.usajobs.gov/GetJob/ViewDetails/304776500

You must apply online and applications will only be accepted for 1 week (Jan 3 - Jan 10).  As
noted in the announcement, the major duties of these positions involves sampling small streams for fish via backpack electrofishing.  Two positions will run from early April through late August with the other two positions operating from late May through late August.  The positions starting in
April will assist with macroinvertebrate monitoring early in the season. The positions will be based in Luray, VA.

Most of your questions should be addressed in the job announcement on
USAJOBS.  If you don't find answers there, contact Jeb Wofford ([log in to unmask]).