Clayton Industries Incorporated of Pittsburgh, Pennsylvania, proposes storing nuclear waste along the wall in trenches that are at least 30 metres deep.
Money already collected by the US Department of Energy from people who benefit from nuclear power would help pay for the wall.
The bid includes an option for hardware to convert the nuclear waste to energy.
2. ARTWORK
Concrete Contractors Interstate of San Diego, California, proposed a polished concrete wall augmented with stones and artefacts specific to areas on the 3220km border.
Russ Baumgartner, CEO of the company, says the wall should be "a piece of art".
Customs and Border Protection's specified the wall should be "aesthetically pleasing" from the US side, but Baumgartner wants to decorate both sides.
3. TOURIST ATTRACTION
Crisis Resolution Security Services Incorporated of Clarence, Illinois, proposes a wall that is 17 metres high and seven metres wide at the top - allowing plenty of room for tourists to enjoy those shimmering desert views.
The height - nearly twice what the government envisions - would deter climbers, and its width would give the structure longevity, said chief executive officer Michael Hari.
4. SOLAR PANELS
Gleason Partners of Las Vegas, Nevada, proposes solar panels to cover sections of the wall.
The panels would provide power for lighting, sensors and patrol stations, and the company said selling excess electricity to utility companies could cover the cost of construction in 20 years or less.
"I like the wall to be able to pay for itself," said managing partner Thomas Gleason.
5. BALLISTIC CONCRETE
DarkPulse Technologies of Scottsdale, Arizona, proposes a concrete wall that can withstand tampering or attacks of any kind.
"You could fire a tank round at it and it will take the impact," said company founder Dennis O'Leary.
Fibre sensors would be embedded in the concrete to immediately alert officials to any attempts to climb over or tunnel under the wall. It would be coated with a slick coating that would prevent climbing.
6. NO BORDER
Otra Nation, a group of American and Mexican citizens, proposed the world's first shared co-nation along the border "open to citizens of both countries and co-maintained by Mexico and the United States of America".
It would also create "nodes of cultural production" such as libraries, museums, galleries and workshops between San Diego and Tijuana, Mexico, and other spots with cities on both sides of the border.
It also aims to prohibit oil drilling and mining and create a "hyperloop transportation system" for people and cargo along the route.
NEXT STEPS
The bids came after the Department of Homeland Securities released an extensive list of requirements last month, specifying it had to be "physically imposing" and "aesthetically pleasing in colour" from the US side.
Officials from the Department of Homeland Security will now create a shortlist, before asking a number of bidders to build prototypes in San Diego.
With a budget thought to be somewhere between US$10 billion and US$25 billion, truly anything is possible when it comes to the unprecedented project.
