Keoghan said the Rena catastrophe had already been and gone from United States television news but he hoped that by coming to the beach he could revive international news coverage.
"It's gone. It was a news story but unfortunately the way news works is, 'What else is happening? Tell me something new.'
"I'm not here to clean up the beaches, I don't have the resources to do that. What I can do is come here and at least draw some attention to it and make sure this story stays in the news," he said.
Keoghan knows Mount Maunganui well. In 2009, he brought his multi-Emmy award-winning show, The Amazing Race, to town.
As part of the New Zealand leg of the show, contestants were required to race up Mauao.
"We had The Amazing Race here and they actually ran up the Mount. So The Amazing Race fans know this.
"So now race fans are going to connect this. We've put it back on the map but this time it's a little more serious," he said.
The outlook of the hazard still lurking off the coast was frightening, he said.
"When I heard it [the Rena oil crisis] was here, I thought of the time we were here for The Amazing Race [and] suddenly it had a whole different perspective. I've been watching it with great interest from overseas.
"My first thought was, 'What's going to happen to the beaches?' We've got a thousand tonnes of oil in a ship out there," he said.
In full recovery outfit including body suit, gumboots and gloves, Keoghan spent about quarter of an hour helping the beach volunteers. "What's really nice is to be able to see it and meet the volunteers. [I spent] maybe 15 or 20 minutes on my hands and knees - it's back-breaking work and frustrating."
The warm weather yesterday altered the consistency of the oil still on the beach and made it difficult to collect, he said.
"It was dripping through the shells. You wish there was some way, some special machine that would just suck the oil and leave the sand clean," he said.
Keoghan was in the country for only 72 hours before flying back to Los Angeles, where shooting for his reality television show was set to restart.
He said there were positive and negatives to take from the ship's grounding and the subsequent clean-up operation.
"Look how the community has rallied together, just like Christchurch [after the February earthquake].
"The most important thing is there isn't a lack of volunteers," he said.
"It goes to show the really big difference with this crisis [compared to Christchurch], is this situation was avoidable.
"That's the sad part of it. It didn't have to happen."
