For some Southeast Valley companies, every day is Earth Day.

The observance began in 1970 when Wisconsin Sen. Gaylord Nelson initiated a movement urging Americans to be environmentally responsible. His idea was met with enthusiastic demonstrations by 20 million Americans, many on college campuses, and led to the creation of the U.S. Environmental Protection Agency later that year.

The 40th anniversary Earth Day will be observed Thursday, and The Mesa Republic is taking a look at four local businesses that use "green" practices 365 days a year.

Banner Health

The health-care provider is Mesa's second-largest employer. It is saving tons of land waste by recycling more of its day-to-day equipment and supplies.

Last year, Banner, which serves seven Western states, saved $2.1 million in supplies companywide by trying to be more green. In Arizona, Banner hospitals collectively saved 61,000 pounds of waste by sterilizing and reissuing unused surgical tools.

In fact, Banner Gateway Medical Center in Gilbert, which serves parts of east Mesa, was given the 2009 Healthy Hospital Award by Phoenix-based Ascent Healthcare Solutions. The hospital reduced supply costs by $251,386 and reduced the amount of waste by 9,164 pounds, nearly 5 tons.

Several years ago, the hospital began reprocessing some of its supplies, said Sarah Remington, Banner's environmental compliance coordinator.

"When an operating room is set up for a certain procedure, they get set up with a specific surgical package. The surgeon may use one instrument," said Remington adding that the rest of the tools were thrown away.

Now tools are sterilized, rebuilt and repackaged at a Phoenix-based reprocessing company for single-use medical devices.

"Sharps" containers - those red plastic bins used for disposal of used medical needles - also are reprocessed, saving money and cutting waste. Banner started a voluntary environmental leadership committee four years ago, now called the "Think Green" team.

"It gives us a way to communicate to our employees and outside entities to know what is going on," Remington said.

She said the volunteers develop eco-friendly projects for the hospital. "We're doing it in an engaging environment. In doing that, they (have) saved a lot."

The Boeing Company

Most people know Apache helicopters are made in Mesa. But they may not know what the major defense contractor is doing to be energy efficient.

Boeing, Mesa's third-largest employer, is replacing its four massive air-conditioning chillers with new, more energy-efficient models. The company replaced two chillers several years ago and recently spent $1 million to replace two more as part of a five-year project. Two more chillers are planned for the the 348-acre campus. The Mesa facility recently received a $100,000 rebate check from Salt River Project's PowerWise Business Solution program for using energy-efficient methods.

A chiller generates cold liquid that that is blown onto a cooling coil to cool a building. Carl Luther, a senior facility analyst, said the new system is 30 percent more efficient than the older ones. Luther said the company has always taken efforts to conserve the environment. He said the company recently started a volunteer program called BEEP, or Boeing Employees for Environmental Protection.

"A lot of our customers are environmentally conscious, Luther said, adding that customers like to know that the process in which their products are being made is done in an eco-friendly environment.

WAXIE Sanitary Supply

Earlier this year, the California-based sanitary supplier built a $12 million environmentally responsible building in Mesa that has received Leadership in Energy and Environmental silver certification by the U.S. Green Building Council. The 103,000-square-foot, eco-friendly building is one of several that represents the company's efforts in providing sustainable products.

The Mesa facility was designed with solar-power and water-saving technology. It also has energy-efficient features such as window glazing, which provides natural light, but reduces solar heat from coming into the building.

Staff and customers who use alternative transportation can use bicycle storage, showers and changing rooms, or they can receive preferred parking if they drive a low-emission vehicle.

Clean Air Cab

Another Mesa business took a green approach in transportation services.

Clean Air Cab is taking the high road in reducing carbon emissions with green-friendly vehicles. Steve Lopez, who owns the Mesa taxi service, uses 29 Toyota Priuses, a fuel-efficient hybrid vehicle. The cab company opened last fall. Since January, it has seen a 20 percent increase in business.

"I think the biggest thing is they really notice how nice it is," said Jorn Bates, the company's chief operating officer. He said customers say they like the newness of the car and how nice it smells. "They actually call our cab cute."

The company is also involved with Maryland-based Trees for the Future, a non-profit organization that promotes and supports the planting of trees through self-help projects with community groups, individuals and businesses.

"We plant 10 trees per cab every month," Bates said. "We want to be ecologically responsible. It's the right thing do. So we spend a little more money in doing that. So far we've planted 1,540 trees," he said.

Bates said the cab company was not affected by Toyota's recent recall. He said a local dealership replaced his fleet's brakes within 24 hours.

"I think the benefit in the underlying tone is most people care about being picked up on time and price," said Bates, adding that when customers learn how they are participating in being green, they see it as another bonus.

"Our costs are lower than the top four (cab) companies in the Valley. We like to say that we're the lowest (fare) and pass the savings onto our customer," Bates said.