In fact, at 18 million sf, the eight buildings on 76 acres is the largest planned LEED project on record. It includes a 4,000-room casino hotel; two 400-room non-gaming boutique hotels, 500,000-sf retail and entertainment district and 2,650 residences and will open in 2009.

In her spare time, Ortega oversees all environmental strategies for the company's 16 projects. Yet, she stole an hour to talk with GlobeSt.com about the challenges and surprises that emerged as CityCenter grew green from a clean slate.

GlobeSt.com: Were there other projects that served as a model for the entire CityCenter project or its components?

Ortega: If anything, it was the opposite. We spent three or four months really looking under the covers of sustainability in environmental building. We wanted to make sure we weren't getting a hold of some fad.

I visited some beautiful office buildings and campus settings and residential settings, and what I saw actually made me more nervous about our ability to do it for a high-end project like this. It's high end across the spectrum: the residential and retail components, and our casino component needed to be the most beautiful and best offering that's ever been built.

At the green projects we went to see, we saw carpet that was much different than carpet we would use in this kind of offering. We saw that an indoor office occupant has a different expectation than the indoor occupant of a luxury hotel. The visits actually made it a bigger challenge for us to decide to take the whole project LEED silver.

GlobeSt.com: What special considerations came into play because of the sheer size and mixed-use nature of the project?

Ortega: The residential and mixed-use portion is sitting in the heart of such a great wealth of things to see and do, so it's not straight residential. I've been in some green residential projects, and the people who buy there really expect to get the look and feel of a green building. I don't believe in a mixed-use, high-end project like this that's the expectation. Because many of the residential units are second homes for people, they expect them to be more like a hotel and have the same amenities and services of a hotel as opposed to their homes.

The retail application is a core and shell application. We have a program to train the tenants. We put them through a training program that begins with raising awareness. We talk about the benefits of environmental fitouts, and we talk about how environmental fitout can be done easier than they might have thought. We really provide the framework for them.

GlobeSt.com: Have you met with resistance?

Ortega: I think there's always resistance, because there's so much risk in the marketplace, especially now with the economy. It isn't that people are resisting environmental responsibility. What people resist is change. When you're running a project that has such a high budget and strict timeline -- this is really fast track -- change isn't your friend. Across the whole fabric of the project, everybody wants to do what they've always done that worked.

GlobeSt.com: How have you overcome resistance?

Ortega: That's part of what being a sustainable company is all about. Raising awareness and making a business case for environmental sustainability is a primary goal of the company. And we've applied it to our competitors.

In the very beginning I think we designed the mousetrap first –the big casino mousetrap. We sat down with our senior executives in the company and said, look, we can help them or we can let them go their own way. We were talking about competitors of ours. We decided to work with them.

We were able to show them the way around some very large obstacles. It's like pulling back a slingshot. And when we let go and they took off on their trajectory, they're doing wonderful projects. We're pretty proud of that. A lot of big projects here in Las Vegas are pursuing sustainability.

GlobeSt.com: Most people assume building green carries a premium. Does it?

Ortega: Certainly.

GlobeSt.com: Can you quantify it?

Ortega: From a materials and construction standpoint, it's difficult, because you get into the discussion of what would you have done anyway. Many of the energy and water efficiencies we pursued are the kinds we pursue on any project.

So, for me to say, MGM, this is our baseline and everything above that is incremental, is probably a little disingenuous. For example, we have a combined heat and power plant. Yes, we scored significant LEED points because of that. I don't know if we'd have done it otherwise.

The construction and design trades talk about premium in terms of construction costs. From that perspective, it is in the range from 1% for an academic setting to probably 3% in a large office setting. I think it's fair to say we're probably on the low end of that.

But, for us the premium is way different. That's not really where the premium is in a large project. In a large project, the premium is in the smaller mark up points you're dealing with to get the products you want. That adds friction to a process that needs to have very little friction.

For example, I went to China last year to research a company that could produce a certain kind of wood component for cabinets. There are plenty of doors available in the US. But for us to buy bathroom cabinets for 4,000 hotel rooms, we really had to reach deep to find not only the products we wanted but the contractors that were willing to warrant their work and work on this scale. A decision that normally would have taken weeks, took us months to find what we needed.

Meanwhile, the project is moving along. For us, (the premium) has been about risk. How do you sustain the goals of the project while at the same time doing so is slowing the project down?

GlobeSt.com: Isn't your sheer buying power beneficial?

Ortega: I'm not sure it's as beneficial to us as it is to the projects that come after us. The water fixture is a good example. It took us time to sort through what was available in the market and find that there really wasn't a shower head for the hotel rooms that we really thought was at the level we needed for our guests and yet met our water requirements. We spent a lot of time on design and testing units in our hotels. It was a process for us. Those fixtures will probably end up in every hotel. We do, however, have the financial wherewithal to loan a company money for research and development.

GlobeSt.com: Aren't there proven technologies that were useful?

Ortega: Yes, more environmental technologies are coming along all the time. There are many different types of technologies for handling water, for example. But, if you're here in the arid desert, many of those technologies don't make sense, because there isn't enough rain to justify them.

Solar power's another very good example. In a project that's highly dense, the solar application doesn't really make sense because the amount of space you have to lay over isn't big enough to really generate the amount of electricity that would be beneficial. That would be more of a 'show' application.

We put a primary focus on indoor air quality, from initial design through construction and materials to eventual operation. We believe that it's a competitive advantage for us to offer healthier residential buildings. We looked at The Solaire in Battery Park and were told they believe they are receiving a 6% higher rent on that building because of the indoor air quality.

GlobeSt.com: What do you consider the most innovative of the project's green features?

Ortega: I can't single out the most innovative, but I can tell you my favorite. I believe the Pelli (central) structure is going to be an iconic building. It is a crystal; it is beautiful, and they did something they haven't done in other designs. They used these little window shades called bris soleil, sun-shading devices, that give the building just a different look.

We really looked for the performance in the glass. They tried different colors, different types of glass, different heat transfer and then created an architectural bulls-eye. They just nailed it. The result is beautiful yet highly energy efficient even though it's a crystal building.