The site, which employs approximately 650 people, has confirmed there have been 17 positive cases of coronavirus among staff.
"The safety of our team and their families is our number one priority and we continue to maintain the highest level of vigilance to help prevent the spread of the virus and to protect our people," a spokeswoman for PepsiCo said.
"Under no circumstance would we ever knowingly allow somebody who is symptomatic or Covid-19 positive onto any of our sites.
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"We have had extremely strict measures in place at our sites to protect our employees’ health throughout the pandemic, these include rigorous cleaning regimes and strict social distancing rules throughout our site."
PepsiCo, which manufactures Walkers, said they have hand washing facilities and temperature checks at the site entrance and "further, regular hand washing is expected and adhered to".
They also said they are reinforcing the government guidance to all their employees to 'act as if you have the virus', masks are mandatory and social distancing is enforced.
The spokeswoman added: "We are also working with the governments to roll-out regular testing at our sites to identify asymptomatic cases.
"This initiative is in addition to the health and safety measures we have in place to keep people safe.
"We are in regular contact with the local health authorities and government bodies and are reassured that we have all the correct measures in place to protect our employees."
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