I am in a similar situation. I want to redo my old kool deck. I'm wondering if a composite decking would work. Please let me know if you decided what to do with yours and how it turned out.

You don't need to hire somebody to compact your dirt. And there's probably nothing in your code about compacting fill dirt. Dirt will compact naturally. It's called gravity. It's how dirt gets compacted naturally in the wild. It's how people survived for thousands of years without expensive earth tamping equipment. It can be a slow process, but it's free. A foot depth of dirt will compact to within an inch of its final resting level within a week or so. A swimming pool full of dirt will compact to within a couple inches of its resting level within a month or two. A year later, you may notice the level has dropped an inch or two. But that's it. If you're walking on it or dragging a wheelbarrow over it, you're going to speed up the process, and you'll feel how compact it is. If you spread it evenly and fill it slowly, there's no chance of it "collapsing" underfoot like these contractors want to scare you into believing.

You should take a few pictures of the problem areas as this can help us to better understand the severity of your problem. Sometimes the deck needs to come out and sometimes you can just ignore the problem. Also, slab jacking and grinding down tripping hazards are also options depending on your situation. As for the liner, be sure that your coping will last at least as long as the new liner before you change it - otherwise it needs to go also. Mil is a scientific unit of measurement where gauge is not a standard unit of measurement (meaning gauge can vary in actual size, mil can not) - The liner you want is the 27 mil which is often called 30 gauge - this is a terminology issue. This new liner will be the same thickness as your last one. Used to be that 30 mil and 30 gage were terms thrown around. Actually, even still they are. If you were to actually take a micrometer and measure your liner you would see that neither the new ones or the old ones are actually 30 mil. They are supposed to be 27 and they are not even that. Most are actually between 22 and 26 mil with floors often being thinner than walls. That is the result of most vinyl sold in north america coming from overseas now. Quality is lower. Buying from USA or Canadian suppliers is not enough - most are still overseas vinyl deceptively labelled as "made in USA" which in the fine print says vinyl from China which has been seamed together in the USA.

As the pros above have noted, it's possible. However, the real question is, do you know whether the previous pool was actually fully removed or just filled in? Depending on your location and the local code, two types of so-called removal may be allowed. A partial removal, i.e. filling in a pool, is the cheaper way to go and if it's allowed, that's what many people choose to do. A partial removal involves a demolition contractor removing the coping, the tile, and the top few feet of the liner. Then holes are drilled in the bottom of the liner for drainage and then the pool is filled with dirt and other fill materials (sometimes the code allows dumping the debris from the demolition of the top few feet in with the fill). In certain localities, if a pool is only partially removed, no new pool can be put there unless the original pool is dug up and fully removed (see below for what full removal entails). Additionally, a partial removal may need to be disclosed when selling the home since it might prevent someone from installing a pool in the future. A complete removal, when done correctly, leaves no trace. During a complete removal, the entire liner, coping, bond beam, structure, etc. are demolished and all debris is removed from the site. The hole is filled with clean-fill soil in and compacted at regular intervals as it's filled so that the compaction matches 95% or more of what nature could do. Typically a soils engineer would have been involved in this process and regular samples should have been taken to indicate that the compaction of the fill is sufficient to avoid creating a sink hole or further settlement. Often times a permit is necessary for a complete removal and the city will inspect to ensure the proper protocol has been followed. When finished, it is basically as if a pool were never there, so putting a new pool in at the same location should not be an issue. There is no need to disclose a prior pool in many cities because the old one was completely removed.