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The cracked and cratered Washington Monument is now well on its way to full repair after billionaire investor David Rubenstein donated $7.5 million to fix the damage  caused by an August earthquake.

Rubenstein's gift is the largest ever made to the Trust for the National Mall and is his third multi-million dollar donation to the nation's capital city in the past year.

"America has been very good to me, and I am humbled to be able to honor the father of our country in this way," Rubenstein said today in a statement.  "Reopening the monument as soon as possible will help ensure that many people get to learn about American history and the unique role that George Washington played in the birth and life of our great nation."

The Washington Monument has been shuttered since Aug. 23, after a 5.8 magnitude earthquake literally rocked the foundations of Washington's tallest monument, cracking its marble exterior, damaging its elevator and creating a 4-foot long, one-inch wide crack that visitors could see daylight through.

With the now $15 million repair fund, half of which was appropriated by Congress and half of which came from Rubenstein, the Park Service said it expected the repairs would be completed by August 2013.

Rubenstein, a prominent D.C. philanthropist, is the co-founder of the global private equity firm the Carlyle Group, which handles $148 billion in assets, according to the firm's website. He is also the chairman of the John F. Kennedy Center for the Performing Arts and a regent at the Smithsonian Institution.

One month ago, Rubenstein rescued the National Zoo's giant panda program with a $4.5 million donation and seven months ago he wrote a $13.5 million check to the National Archives to create a new gallery that will display a 1297 version of the Magna Carta, a copy he owns and will lend to the museum, the Washington Post reports.