Last summer I was shocked while using my inground swimming pool. The pool is probably 35 years old. We have owned the house for 18 years. After I was shocked, an electrician came and found that there was no GFI nor was the pump grounded. Thought it was fixed. Earlier this year, after sticking his hand in the water, my husband felt a small tingle/shock. The pool service tech said it was the light switch and changed it out. I was not satisfied so I called another electrician. He could not find anything. Said everything was OK. I was still not satisfied, so called another pool contractor who came with his electrician to check it out. They said the only thing it could be would be the light; maybe it is not grounded. They also recommended grounding the steps and slide (I've since learned that they must of meant bonding).

They are going to charge me $2300 to bond the steps and slide. They say they have to dig up concrete, etc.

Does this sound right?

Sure, if they have to dig up and replace concrete. I'm thinking it's kind of expensive, but possibly worth it. A GFCI (GFI) should trip if more than 5 milliamps of current passes to ground. They're pretty sensitive.

From what you said, the light / light switch is the only electrical device that makes contact with the pool. Even so, it's recommended to bond the ladder and the slide.

Make sure the light is grounded. Use an ohmmeter to measure continuity to the grounding block of the circuit panel. Make sure the light switch is also grounded. Make sure the GFI is properly installed and all current bound for the pool is going through the GFI.

There are a whole lot of regulations pertaining to swimming pools and they all relate to "equipotential bonding". You can read NFPA 70 (NEC) by following the instructions in the sticky in this section.

The concrete, ladders and anything metallic must be bonded. Usually, the concrete grid must be inspected before the concrete is poured.

You had to be touching something and the water to be shocked. Foot on wet concrete, ladder etc. with your foot in the water.

There is also a gradient across the earth.

Have your electrician put his money where his mouth is.
What happens if bonding his suggestion doesn't work?

Those potentials can be measured. Take a square foot plate of clean metal and place it in the pool and start measuring voltages and currents to various metallic parts.
Something should show up. If not, you'll have to look at ground gradients and the utility bonding.

GFCI's won't work.

Water and electricity are a dangerous combination. The minor shocks you received were a warning.

Get a couple quotes to make sure they are all in the ball park After 35 years, the whole system needs to be checked out and probably replaced.

$2300 won't buy you much of a funeral.