Coral reefs are large areas of hard coral where many animals live.
The coral looks like rock but it is alive.
The hard coral is the outer skeleton of the animals.
They create the reef.
Coral reefs are very delicate areas.
Many different kinds of animals live in coral reefs.
The coral reef in Arecibo is part of the beach.
The pollution was harming the coral and all the animals living there.
A healthy reef makes good surfing waves.
If the reef becomes damaged, the surfing may not be as good.
The waste coming out of the pipe was damaging the reef in Arecibo.
So why was the pollution being pumped onto the beach?
Well, the United States Army Corps of Engineers was clearing an area of the sea floor.
They were digging up the material to make a better pathway for ships.
But this man-made path was very dirty and polluted.
The United States Army was allowed to pump the waste onto the beach because Puerto Rico is a commonwealth of the United States.
The United States has an army base on the island.
The army needed to make sure that their ships could reach the base.
But Angel did not think they needed to pump the waste onto the reef.
Angel went back to tell his friends what was happening.
The news made them angry too.
They made a plan to stop the Army Corps of Engineers from ruining the coast.
They went down to the beach.
They stood on the pipe that was pumping the waste.
When the flow of waste stopped, the men stood inside the pipe.
Each man stood in the pipe for four hours.
After the four hours finished, another man stood in the pipe for another four hours.
The Army Corps could not pump waste out of the pipe if people blocked it.
The Army Corps did not think that it was doing anything wrong.
But to the surfers, it appeared that the Army Corps was breaking United States environmental law.
So Angel Rodriguez decided to sue the army.
He brought them to court in protest.