Just coming out of lurkdom to mention Hazmat would be called in for anything involving human waste (i.e. sceptic). It doesn't necessarily imply drugs. There is also the possibility it was an accident:
http://www.nj.com/hunterdon-county-...ank_in_tewksbury_family_warns_of_dangers.html
http://www.nj.com/hunterdon-county-...ank_in_tewksbury_family_warns_of_dangers.html