By Beth Germano

BOSTON (CBS) – It was a revelation for cleaning crews as they removed test samples of a cleaning solution from the World War II memorial in South Boston. It revealed oil-free, clean patches, and plenty of hope. “We crossed the start line. I can reach the finish line with my hand pretty soon,” said Ralph Morgan with the cleaning company Prosoco.

It was a breakthrough after a frustrating few days trying to figure out how to clean the oily substance that was spattered on the revered names of the memorial, and seeped into the porous stone.

READ MORE: Keller @ Large: Candidate Jon Santiago Says Boston Mayoral Race 'Transcends Politics'

“We definitely have a direction to work with now. One of the samples seemed to work out pretty well,” said Robert Shure who designed the memorial.

READ MORE: 'Unthinkable Loss': 2 Cousins Drown While Skipping Rocks At Waldo Lake In Brockton

Worker attempts to clean vandalized WWII memorial in South Boston (Image credit Beth Germano)

But there are challenges since the mixture works better in warmer temperatures of about 50 to 60 degrees, and crews at the Castle Island site worked in windy, colder conditions. They brought in heaters to warm up a smaller section of stone, and then went to work covering it with the new solution that will provide another test sample and reassurance it’s the answer for the entire memorial.

It’s all something 94-year-old Rosario Charles, a World War II veteran, is still trying to understand. “There’s no answer for it. I guess I don’t know that these kids are doing and I don’t know what they’re learning,” said Charles.

MORE NEWS: 6 Rescued After Boat Overturns In Cape Cod Canal

Now it’s a waiting game and they’ll need help with the temperature from Mother Nature or a tent may be brought in to get the job done faster. “It’s a punch in the heart for what happened here,” said South Boston resident Bob Cahill.

Beth Germano