References
http://jchemed.chem.wisc.edu/Journal/Issues/2006/FebACS/ACSSub/V83N02/p240A.pdf
http://www.hawaii.edu/gk-12/evo/hector/islandschool/soil1.pdf
http://www.hawaii.edu/gk-12/evo/hector/islandschool/soildatanalysis.pdf
http://drscavanaugh.org/sodabottle/bottle.htm
http://ga.water.usgs.gov/edu/wwvisit.html
http://www.teachersdomain.org/resources/ess05/sci/ess/watcyc/h2otreatment/index.html
http://www.waterandwastewater.com/videos/view_video.php?viewkey=84325132fca8edcdfb40
http://ga.water.usgs.gov/edu/earthgwaquifer.html
http://capp.water.usgs.gov/aquiferBasics/
http://www.gma.org/katahdin/aquifer.html
http://www.groundwater.org/pe/so_aa.html
http://www.enotes.com/earth-science/porosity-permeability
http://www.classzone.com/books/earth_science/terc/content/investigations/es1401/es1401page04.cfm
http://www.ocrwm.doe.gov/info_library/program_docs/curriculum/unit_4_toc/24.pdf
http://www.wma-minelife.com/bent/bentmine/data0000.htm
http://www.trainweb.org/wyomingrails/wymining/wybentonite.html