South Florida developer R. Donahue Peebles keeps threatening in letters and mailers that he will build a "big box" store if voters reject Measure L's blank check for 355 houses. Then in public he apologizes for making the threat or denies that he made it. Then the next mailer repeats the threat.
The fact is, as numerous people have pointed out, if there were a market for a big box store in the quarry, one would have already been built or at least proposed. No big box store wants to come here because there isn't sufficient population within a certain radius to provide the market. Big chains use a formula for deciding where to locate. Half of a circle drawn in the quarry is ocean - there simply can never be enough population within, say, a 10-mile radius for any big box store to locate in the quarry. That's why they're all over the hill.
Also, many people have pointed out that nobody builds a big box store on spec. That is, the tenant must be identified in advance before a big box would be constructed.
All in all, I'd argue that the likelihood of a big box being built in the quarry is close to zero. It's an empty threat, meant to intimidate us into voting for his 355-unit housing development.