Kia rio ice 2003 hatch has water collecting in puddles underneath rear seats and edges of boot???

Yes they do

Open the back trunk, look near the top of the trunk, and pull the two black levers. They have a seat folding down symbol. That will release the locks.

DO NOT DRIVE THIS VEHICLE! This is a serious fire hazard!
Did the gas flood the inside of the car?
This sounds like the access panel they removed to replace the pump has not been refitted correctly. Contact the mechanic who did the work as they are responsible for the work done.
Discuss the issue in a CALM and POLITE way to organise what is to be done next. As this involves Gasoline they need to be involved in sorting out this SERIOUS mistake.

If you can get the rear hatch trim off with the door closed, then you could release the lock mechanism from the inside. If you cannot get the rear hatch trim off, then you will have to do this from the outside. Either the locksmith can key it while still in the car, or you will have to destroy the old lock and get a new one.

Take out the head liner and check for bad welds on the upper body

It should be an exact fit.

If you need further help, reach me via phone at https://www.6ya.com/expert/steven_a67ead41eb5fc62a

Sounds like a heater core to me, does it smell a little like antifreeze?

call a lock smith they can make you a key right there on the spot,that is if they are as good as my GUY.

remove the rear seat 2 12mm bolts in bottom on front then lift seat out you will see access panel fuel pump under there

We had the same problem.
I took out the bolts outside, then crawled into the back area of the car, and took a screw driver, and slid it along the inner hatch catch, and found the safety latch and released the hatch. Then I took the inside off, and disconnected the handle device from the inside. It was rusted, and broken. I went to Kia, and bought a new one and reinstalled, after greasing the new one up. Took me a while, but they wanted 280.00 in labor, so it was well worth it.
Just be patient and go slow. A good metric socket set will be the best thing, with a regular and phillips screw driver.
Good luck
David

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