An investigation is underway after flytippers dumped woodchip and commercial waste in a car park near Talybont.
Gwynedd Council say the tip was left at Aberogwen at some point between last Monday afternoon and Tuesday morning. They warned that offenders could face fines of up to £50,000 or even a jail sentence.
Anyone giving their waste to a trader could also be fined up to £5,000 a day for breach of duty of care if it is found dumped.
Anyone with information about the flytipping is urged to contact the Street Enforcement Service at Gwynedd Council on 01766 771 000 or firstname.lastname@example.org – alternatively, contact Crimestoppers anonymously on 0800 555 111.