Statement 1 is clearly not sufficient. Statement 2 desperately needs a copy edit ("the total the water in in the pool"?), but mathematically, we know that 3000 gallons corresponds to 3/8 of what is currently in the pool. So there must be 8000 gallons currently in the pool. Since that's 25% of the total capacity, the total capacity is 32,000. So Statement 2 is sufficient and the answer is B.

The typos aren't the only problem with the question. The two statements are completely contradictory - Statement 1 says there's 9000 gallons currently in the pool, and Statement 2 says there's 8000 gallons currently in the pool. If you try to combine the Statements, the math won't make any sense. In real GMAT questions, the two statements can never contradict each other, and I always get a bit concerned when I see questions from sources that can't even observe that basic principle of DS question design.

Ditto what Ian said. This is one of numerous glaring errors from this source, so I'd strongly recommend that you find other sources of study material.

Here are several other questions from this source with glaring errors:
https://www.beatthegmat.com/women-s-suff ... tml#576023
https://www.beatthegmat.com/pacific-ocea ... tml#576108
https://www.beatthegmat.com/seat-belts-t ... tml#576110