Engineers controlling a quality of water ,aerated activated sludge tank at a waste water treatment plant
Keywords
aeration,
cleaning,
controlling,
ecology,
engineer,
factory,
hard hat,
helmet,
horizontal,
male,
man,
microbiology,
one man only,
outdoors,
people,
pipe,
pollution,
protective clothing,
quality,
quality control,
sewage,
storage tank,
tank,
teamwork,
test tube,
two people,
waste,
water,
water treatment plant,
men at work,
working,
working out