The first dump was discovered near the Dundonald Road area of the Moorfield Industrial Estate in Kilmarnock.
SEPA stated that it believed the waste was deposited over a week-long period between 22 and 29 December 2025. Officers say the scale of the deposit indicates organised activity rather than fly-tipping by individuals.
A second illegal waste site was reported on 30 December 2025 at the IMEX Business Park in Lugar, also known locally as Lugar Works.
The vehicles involved in this incident travelled through Muirkirk to Lugar between 4pm and 6pm on the day the waste was dumped, according to SEPA.
Kirsty McHarg, Southwest Scotland Unit Manager at SEPA, commented: “From the reports received, it seems this dumping has been done by white sided lorries.
“We believe those responsible travelled through both locations and hope this appeal may jog memories, or that people with dashcam footage or with access to CCTV in these locations might have spotted something that might help our investigation.”
SEPA calls for public information
SEPA have now urged members of the public to come forward with any information that could assist the investigation.
McHarg added: “Additionally, we’re asking members of the public to continue to be vigilant and report anything suspicious to us.
“This could be unusual vehicle movement or activity at unused sites.
“Landowners should also be alert to the risk of their land or premises being used for illegal waste deposits.”
SEPA warned that illegal waste dumping is not only unsightly but can pose serious environmental risks, including the release of harmful gases and liquids as biodegradable waste breaks down.
The agency added that waste crime places a heavy financial burden on the public purse, costing taxpayers tens of millions of pounds each year through clean-up costs, avoided tax and lost revenue.
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