You are responsible but it never hurts to ask them about it. I have a pool company close my pool and after opening this year I also had a leak. The ground around the pumps was getting wet when running. I found one leak, it was the drain plug in my booster pump. I pulled it out cleaned and lubed it and put it back in. No more leak. However, the ground was still getting wet. I couldn't see where it was coming from. Pool guy took a look and found that it was the seal between my main pump and motor. We had a super cold spell here this winter, the highs were only around 5 degrees for a while. Maybe that cold had something to do with it, maybe not.