A man who threw away a laptop hard drive containing bitcoin he believes is now worth about £210m wants his council to let him search for it in landfill.
He said he was willing to donate 25% of the value of the bitcoins to his home city of Newport in south Wales - about £52.5m - if he found the hard drive.
Newport council said excavation was not possible under its licensing permit.
Mr Howells said if he was to recover the hard drive, he would want the money to be put into a "Covid relief fund" for people in Newport to use "no questions asked".
"Imagine how great it would be to say 'I've given everyone in the city a few hundred pounds'," he told the BBC.
Mr Howells bought the bitcoins for almost nothing in 2009, but the hard drive ended up in a drawer after he spilled a drink on his laptop.
He kept the hard drive in his office drawer and "totally forgot about bitcoin all together" - so when he had a clear out, he believed everything had been taken off it.
When he threw the hard drive away in 2013, the value of the bitcoins was about $7.5m (£4.6m).
But now they are worth almost 50 times more, with the cost of a single bitcoin currently just over £28,000 after a surge in value.
He said he has asked Newport council if he could search the landfill several times, but had not been granted permission.
"I offered the local authority 10% of the recovered funds in order to give me permission to search on their property and unfortunately they said no at the time," Mr Howells told BBC Radio 5 Live.
"What actually happened after that was the value of bitcoin skyrocketed even further. In 2017 the value of my hard drive was approximately £125m, at which point I made them another offer of 10% and unfortunately that offer was refused as well.
"I haven't actually made an offer to them today, but I'm willing to increase my offer to them to 25%. On today's valuation that would be £52.5m and I'd like to put that into a Covid relief fund for the citizens of Newport."
Mr Howells said searching for the discarded hard drive would "not be as hard as you might think" as he would employ a professional team - and knows when he threw it away so could use that to find a grid reference of where the hard drive is buried.
He added investors had offered to cover the cost of excavating the landfill, in exchange for a large proportion of the recovered bitcoin.
Mr Howells said he wants to meet with the council to discuss what he said would be a "win-win-win" situation for him, the council and the city.
But a spokeswoman for the council said: "Newport City Council has been contacted a number of times since 2013 about the possibility of retrieving a piece of IT hardware said to contain bitcoins.
"The first time was several months after Mr Howells first realised the hardware was missing.
"The council has told Mr Howells on a number of occasions that excavation is not possible under our licencing permit and excavation itself would have a huge environmental impact on the surrounding area.
"The cost of digging up the landfill, storing and treating the waste could run into millions of pounds - without any guarantee of either finding it or it still being in working order."