Monitoring wastewater in their lab are (from left) Tasman Tanning chief executive Neville Dyer, technical manager Craig Thiele and environmental officer Jerulin Arunkumar. Photo / Laurel Stowell
Three Whanganui businesses who dumped contaminants in their wastewater have not breached their annual discharge limits, Whanganui District Council chief executive Kym Fell says.
The breach data was revealed by RNZ in a story in the Whanganui Chronicle, January 27.
Two of Whanganui's Talley's Group meatworks and the Tasman Tanning factory were at the top of the table.
Talley's Affco and Land Meat meatworks breached daily contaminant limits 709 times in the past year, dumping
Tasman Tanning's contaminants were oil, grease and sulphides, plus chromium, a toxic heavy metal used in the tanning process. It had 570 breaches.
However, Fell said industry is measured on an annual rather than a daily basis so the companies where not non-compliant overall. Their daily discharges were often below the limit too.
"Compliance for industrial users is actually measured on annualised average discharges," he said.
For Affco in 2019-20 the annualised average daily discharge of suspended solids and oil and grease was below their trade waste consent limit.
"In the past three to four years Affco has greatly improved its trade waste management in Whanganui," Fell said.
The levels of chromium Tasman Tanning discharged to the Whanganui wastewater treatment plant are higher than the council would like and is of most concern to the council.
Chromium III can affect the growth of the bacteria that break down waste in the council's treatment plant, but Fell said the plant is working well and the company has greatly reduced the amount it is discharging thanks to new equipment in the past two years.
"We monitor discharges to the wastewater treatment plant every day."
The council has a trade waste officer and is highly proactive, Fell said.
"We monitor discharges to the wastewater treatment plant every day."
Chromium pollutes all of the waste, trade waste advisor Tara Okan said, and Fell said it restricts options for disposing of sludge from the plant.
It is stored in a pond in Airport Rd, but space in the pond will run out within four years and it may then have to be trucked to a landfill.
Local Government New Zealand would like councils to be able to impose fines of up to $200,000 on companies that breach their trade waste consents. This has not been possible under current legislation.