Work began in late July to remove an inscription that had caused controversy because critics said the quote had been taken out of context.
But officials ran into problems earlier this week. Sandblasting work to complete the project was left out of the repair contract, and the main contractor, Worcester Eisenbrandt Inc. of Baltimore, didn't have the insurance required to sandblast the surface with an aggregate material called "black beauty." Workers then tried an alternate process to blast the stone using walnut shells, but that left a slight yellow stain.
On Thursday, National Park Service spokeswoman Carol Johnson said a solution had been found. The sandblasting work will be completed by preservation workers from the Park Service's Historic Preservation Training Center in Maryland, under the supervision of the monument's sculptor. Officials have also found a new material for the sandblasting work that satisfies the memorial's sculptor.
Workers experimented with using glass beads to sandblast the surface but have now settled on an aggregate called "jetmag," Johnson said, which looks like a fine powder. The sandblasting is expected to take at most a few days.
The monument's executive architect Ed Jackson Jr., who saw the results of the work that began early Wednesday, said the resulting finish looks the same as when the monument was completed and dedicated in 2011.
"I think it is outstanding. It reminds me of what we achieved two years ago," he said of the work.
Jackson said he believed there was movement toward a resolution of the issue this week because the problem was made public Monday.
The fact that a solution has been found means not only that the work should be completed for commemoration ceremonies surrounding the 50th anniversary of the March on Washington on Aug. 28, but also that it will be done before the memorial's creator, sculptor Lei Yixin, has to return to China. Lei traveled to the United States to do the corrective work and had been concerned he would have to leave before it was finished.
The now-removed inscription was a paraphrase from King's "Drum Major" speech. It read, "I was a drum major for justice, peace and righteousness."
Critics, including the poet Maya Angelou, argued the quotation was taken out of context when it was paraphrased and shortened. Angelou said it made King sound arrogant.
Associated Press reporter Brett Zongker contributed to this report.
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Copyright 2013 The Associated Press.