A plant producing a major component of the product used in mining explosives has begun testing its systems with an eye to begin full production later this year.
The Yara fertiliser plant sits among the rocky red hills of Murujuga, also known as the Burrup Peninsula, just outside town and alongside Aboriginal rock art tens of thousands of years old.
The plant is currently in a "wet commissioning" phase.
Ammonia stored in one part of the site will be combined with other chemicals to form ammonium nitrate
, used by the mining industry to create explosives.
Yara Pilbara manager Rob Stevens said a number of safeguards were in place to protect the community.
"The plant is designed according to international standards, and our management systems around it are linked to Australian standards of operating production facilities," he said.
White or grey plumes of steam will become a regular sight as evaporated water, used to cool the ammonium nitrate reaction, is released through the cooling tower.
At its full capacity, the plant is expected to produce 350,000 tonnes of ammonium nitrate a year, which would be worth as much as 5 million at today's prices.
Construction jobs on the site have almost been phased out, after which it is expected there will be 65 ongoing permanent jobs.