They said the smell might continue for 60 to 90 days, but as the beef plant's discharge treatment processes are fully integrated, the smell will end.
However, they said steps are being looked at to deal with the issue on an interim basis.
"We are sympathetic to those who may experience this on a short-term basis," DuBose said. "We are begging for their patience."
DuBose added, "Everyone is going to do what they can to minimize (the smell) to the fullest extent possible."
DuBose said "everyone" includes the city, Brawley Beef and county Air Pollution Control District officials.
Stephen Birdsall, head of the APCD, said the plant has been emitting odors and air district officials are working with others "to get it solved as fast as possible."
Birdsall added last week it is possible people were affected more by odors coming from the beef plant because of atmospheric conditions known as inversion layers.
Still, he said the goal is to deal with the issue.
"Nobody wants to create a lifelong nuisance," Birdsall said.
Greg Beck, chief operating officer for Brawley Beef, said "We apologize for any inconvenience. It is a temporary issue."
He said the waste pre-treatment process is in a "startup" mode and once that phase has ended, the smells will no longer be a problem.
Some who live near the plant voiced anger about the smell and said assurances it won't last are not enough to curb their concerns.
Lucy Gastelo, who resides on Duarte Street, one of the closest residential streets to the plant, said the stench coming from the facility is so bad it is difficult to go outside her house in the evening.
"The kids don't even want to go play outside," she said.
Gabriel M. Gastelo, her husband, said they moved into the house 17 years ago, adding those who live in the area have had to contend with issues that those in other parts of the city have not faced.
"I don't think they were thinking about the people who live here," Gabriel Gastelo said of choosing to build the beef plant on the Shank Road site not far from residences on the east side of the city. He said he thinks it would have been better if the plant had been built farther from residences.
Lucy Gastelo invited city officials to eat dinner with the family at night and see how bad the smell can get.
Edward Padilla of Jones Street said he has noticed the smell, particularly in the early evenings.
"It smells awful at night," Padilla said, adding he hopes the problem does not linger for 60 to 90 days.
Others said the smell is bad and they are hopeful it will not last. However, they also said they are willing to live with it because the beef plant means more jobs.
Feliciano Duarte, who lives on River Drive, said he has noticed a new smell in recent weeks, although he added he is not sure if it is coming from the beef plant.
He said if it is, he would like to see officials deal with it. Still, he added he is pleased to have the plant in the city because of the jobs.
Still others said they haven't noticed any new smell.
Staffers at Oakley Elementary School, the closest school to the beef plant, said they have not noticed any new smells. They said living in an agricultural area, they are use to certain smells as part of everyday life.
Emilia Castillo, who lives on Jones Street, said the plant has not created any smells she has noticed. She said any smells she has noticed may be coming from nearby cattle yards.
She also voiced support for the beef plant because of the jobs it creates.
About 345 people are employed at the plant and in coming weeks that is supposed to increase to 600 full-time employees. At maximum capacity the beef plant will process about 1,600 cattle per day.
The plant generates waste that must go through a pre-treatment process, and until that process is completely "matured," the odors could continue.
Waste from the harvesting and processing sections of the plant feeds into dissolved air-floatation cells that separate the solid material and starts the pre-treatment process.
The waste then moves into three pre-treatment ponds where bio-stimulant processes break down the discharge further before it moves into the city's wastewater system.
DuBose said the plant has had some difficulties with its dissolved air floatation cells, which means the waste moving into the pre-treatment ponds was of a "higher strength."