A company which operates near Aberdeen Beach is being asked not to discharge radioactive waste into the sea.
Aberdeen beach has recorded traces of radiation
A stretch of the beach was closed last August when traces of radiation were found in the sand.
Environment protection agency Sepa originally identified the recycling company Scotoil as the most likely source.
Sepa later said no link had been established. Scotoil said it had complete confidence in its procedures.
Sepa is proposing that Scotoil finds alternative means of disposing of its waste.
Last August, Sepa said it had found "slightly raised" levels of radioactivity in a very small area of sand on the high tide line at the southern end of the beach near the harbour wall.
Scotoil's waste is in the form of naturally occurring radioactive material produced during oil production.
This is removed from oilfield equipment at Scotoil's premises in Aberdeen and the waste is disposed of by discharge to the sea.
Authorisation to do this was granted in 1995 by Sepa's predecessor body, Her Majesty's Industrial Pollution Inspectorate.
Sepa is now consulting on proposals to change this authorisation.
Proposals include reduced discharge limits and a requirement for Scotoil to implement a new discharge route.
'No significant hazard'
David Orr, of Sepa's radioactive substances team, said: "Sepa grants authorisations that allow the safe disposal of radioactive waste while providing protection for people and the environment.
"The current Scotoil authorised discharge limit is not being exceeded.
"But it is a condition of authorisation that waste disposers use best practicable means to minimise the volume and activity in waste discharged and the chosen waste disposal route must represent the best practical environmental option.
"We would encourage comments on this consultation, which closes on 30 June."
Recent monitoring of Aberdeen beach indicated that levels of radioactivity did not present a significant hazard to beach users.
Sepa said no link had been established between this and Scotoil's discharges.