The federal government has released more details about its plan to build a wall along the border with Mexico through two postings soliciting construction bids for the project.
The two requests call for a "solid concrete wall prototype" and an "other border wall prototype," according to the documents posted on the Federal Business Opportunities website--where the government places contracts open to bidding by the private sector.
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The requests, which come from U.S. Customs and Border Protection, are meant as a precursor for any company wishing for a contract to work on the construction of any portion of the wall.
"The general intent of this acquisition is to award multiple indefinite-delivery, indefinite-quantity (IDIQ), task order contracts for the design and construction of border wall and associated tactical infrastructure/technology along the southwest border," the request states.
The official publication of the specifications comes a little later than was previously stated. Last month, officials said proposals would be available around March 6.
According to the design specifications, the government is planning for a 30-foot high wall, though "designs with heights of at least 18 feet may be acceptable."
The government wants the wall to contain anti-climb topping features which prevent scaling using aids such as ladders, grappling hooks or handholds and prevent digging or tunneling underneath it to a depth of at least 6 feet below the surface.
The proposals call for the construction of mock-ups and full-scale prototypes before the final bids for the actual wall are awarded.
The mock-ups are to be a 10 ft. by 10 ft. section of the prototype to be built in the San Diego area. The government wants the full prototype to be at least 30 feet long, with construction also slated for an undetermined location near San Diego.
The price range for either the concrete or non-concrete options is estimated to be between $200,000 and $500,000, according to the government paperwork.
"CBP issued two RFPs to acquire multiple conceptual wall designs with the intent to construct multiple prototypes. Prototyping is an industry-tested approach to identify the best solution when considering a new product or methodology," the agency said in a news release announcing the proposals. "Through the construction of prototypes, CBP will partner with industry to identify the best means and methods to construct border wall before making a more substantial investment in construction."
Responses to the request for proposals are due by 4 p.m. Eastern Daylight Time on March 29.
Building a wall across the entire 2,000-mile length of the border with Mexico was one of President Trump's most frequent and popular promises on the campaign trail. Shortly after taking office, he signed an executive order aimed at speeding up the process, which is expected to cost between $12 and $21 billion dollars.
For more information on each proposal: