Story highlights The request would include only 48 miles of new wall

The documents also claim that Trump's executive orders are already upping arrests

Washington (CNN) The Trump administration wants the first $1 billion of border wall funding to cover 62 miles -- including replacing some existing fencing along the southern border.

The $999 million requested by the White House in its budget supplement for just defense and border security spending would cover just 48 miles of new wall, according to justification documents from the Department of Homeland Security obtained by CNN.

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The documents describe exactly where the administration hopes to put its first installment of the border wall, as it described its modest 2017 funding ask.

The money will fund 14 miles of new border wall in San Diego, 28 miles of new levee wall barriers and six miles of new border wall in the Rio Grande Valley region and 14 miles of replacement fencing in San Diego. The fencing would likely include concrete elements, a source familiar with the plans told CNN.

President Donald Trump made building a border along the entire US Southern border a centerpiece of his presidential campaign, and repeatedly pledged Mexico would pay for it, but the initial ask for funds to start building has been modest. The administration requested $1 billion in its supplemental for 2017, and another $2.6 billion for border infrastructure and technology in 2018.

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