The second fire to take place at Westhampnett tip in less than two months has been deemed an 'accident', the fire service has said.
The fire took hold of a refuse truck on the site in Stane Street just after 7pm on Wednesday (May 15).
A spokesman for West Sussex Fire and Rescue Service said: "We aren't treating this fire as suspicious; we believe the fire started by accident.
"The fire is now put out and the site is open for green waste only."
Witnesses described hearing 'loud bangs' on the evening of the fire, followed by large plumes of smoke coming from the site.
Speaking at the time, Graylingwell resident Ben Webber said: "We heard three bangs and about a minute later there were large plumes of black smoke in the air.”
On April 2 a much larger fire gripped the household waste and recycling plant. The cause of which was blamed on a lithium ion batteries.
The two are not believed to be linked.