The biggest reason for optimism about investment in all commodities is population growth. Half of the world's 6 billion people live in economies growing at 6 percent a year, but there have been no major gold, oil or copper discoveries.

I keep telling people I don't see explosive population growth. I do see a heck of a lot of building.

It has to do with the growth in population of the whole area. More people are moving in.

In every hurricane I studied, some portion of the population refused to evacuate. People, for whatever reason, often stay and ride it out.

As California's population grows and economic conditions remain healthy, there is likely to be considerable additional demand for, and investment in landfill, waste transfer, material recovery facilities, waste-to-energy plants and related infrastructure.

There's a lot of investment in these kinds of companies these days, so there's a sense of optimism here we haven't seen in five or six years. We have a lot of panel sessions, but often the best ideas are what people think of after two beers at a party or something. It's just a real creative, fertile atmosphere where new ideas come to life.