The Australian company St Barbara shut down its Gold Ridge mine near the capital, Honiara, three weeks ago after the flash floods that killed 21 people and left 50,000 others homeless.
The Solomon Islands Government is worried the tailings dam may fail and endanger the lives of 8,000 people living nearby.
Emilia Wahlstrom from UN's Disaster Assessment and Coordination team, says the tailings dam could contain toxic materials like cyanide.
"The United Nations is here at the request of the government of the Solomon Islands to conduct an independent assessment of the current situation at the tailings dam," Ms Wahlstrom told Pacific Beat.
"(The government) is worried about the consequences of a potential dam breach or just a release of the water of the tailing storage facility into the downstream river and the effect that could have on the communities living downstream," she said.
"Both in terms of the immediate effects and of course then the long term effects of their livelihood and agriculture."
Ms Wahlstrom says there are concerns regarding the integrity of the dam after the floods and the magnitude 8.3 earthquake which hit the country earlier this month.
She says the government wants assistance with assessing the integrity of the dam and also wants to conduct some sampling and analysis.
"Part of our assessment is to see what are the amounts stored there and what's the current composition of the water and what would be the potential effects if something happened," she said.
Meanwhile, the Solomon Islands Government has barred employees of the mine from entering the country to return to work.
Dr Phil Tagini, the special secretary to the prime minister, says several issues surrounding the mine need to be addressed before any moves are made to reopen it.
"As an operation, we want the mine up and running," he said.
"But first it's an opportunity to start thinking about the long-term issues that continue to affect the mine in terms of its profitability... Miners relationships with various stakeholders along the river in terms of affected communities who at the moment have seen themselves to be sidelined."
Earlier the government requested the Australian Federal Police to be deployed at the mining site to maintain security.
The move came after mine owners, St Barbara, suspended operations following the floods in early April.
The Gold Ridge mine recorded 500 milimetres of rainfall in just 24 hours during the floods.
The ABC has contacted St Barbara but no one has been available for comment.