Green Building News

Green Building News September 2002

September 18, 2002

Tests Show Risk from Existing Treated Wood Structures

Results from tests conducted by consumers across the U.S. show that the public remains at risk from high levels of arsenic leaching out of pressure–treated wood in older decks, playsets and picnic tables.

Environmental Working Group’s latest report, “All Hands on Deck,” says that the U.S. Environmental Protection Agency (EPA) was wrong in reassuring the public last February about the safety of existing backyard structures. When the Agency announced that the wood treatment industry had agreed to a voluntary “phase out” of the cancer–causing, arsenic–based pesticide used to pressure-treat the wood in playsets and backyard decks, EPA stated that it did “not believe there is any reason to remove or replace arsenic–treated structures.” But new data show that consumers with old wood structures remain at risk from arsenic that easily wipes off the wood surface. Children who play on arsenic–treated playsets and decks are at particularly high risk.

Since last November, consumers across the country have tested 263 decks, playsets, and picnic tables, and the arsenic–contaminated soil beneath them, via an at–cost testing kit sold through EWG’s website. The samples were analyzed by the University of North Carolina – Asheville’s Environmental Quality Institute. The results of the consumer testing program show:

  1. Older decks and playsets (seven to 15 years old) expose people to just as much arsenic on the wood surface as newer structures (less than one year old). The amount of arsenic that testers wiped off a small area of wood about the size of a four–year–old’s handprint (100 square centimeters) typically far exceeds what EPA allows in a glass of water under the Safe Drinking Water Act standard.
  2. Arsenic in the soil from two of every five backyards or parks tested exceeds the U.S. EPA’s Superfund cleanup level of 20 parts per million (ppm).
  3. Commercial wood sealants lose their effectiveness at trapping arsenic after about 6 months, thus providing no long–term protection from arsenic exposure.

“Consumers had to take it upon themselves to conduct a testing program that should have been done long ago. And now consumers are taking steps to protect their families, as they learn that arsenic levels on backyard decks and playsets remain high for 20 years,” said EWG Analyst Sean Gray.

“The EPA’s advice has misled millions of consumers about the safety of existing arsenic treated wood,” said Jane Houlihan, Vice President for Research. “It’s time that the Agency act to protect and inform consumers,” she added.

Short of replacing their decks and playsets, families can lower their arsenic exposures by sealing the wood at least every six months, and washing hands thoroughly after contacting the wood. They can also replace boards in high traffic areas such as handrails and decking with arsenic–free alternatives.


Sprawl Compounds Drought Crisis

Sprawl development is making the nation's drought even more painful by impairing the landscape's ability to recharge aquifers and surface waters, according to a new report released today by American Rivers, the Natural Resources Defense Council, and Smart Growth America. 

Nationwide, paved-over land sends billions of gallons of water into streams and rivers as polluted runoff, rather than into the soil to replenish groundwater. The report, Paving our Way to Water Shortages: How Sprawl Aggravates Drought, estimates the extent of this phenomenon in 18 rapidly growing cities. The authors urge communities to adopt "smart growth" policies to reign in sprawl and protect water supplies and watersheds into the future.

"Sprawl development is literally sending billions of gallons of badly needed water down the drain each year...the storm drain," said Betsy Otto, senior director for watershed programs at American Rivers. "Sprawl hasn't caused this year's drought, but sprawl is making water supply problems worse in many cities."

The authors estimate that in Atlanta, the nation's most rapidly sprawling metropolitan area, recent sprawl development sends an additional 57 billion to 133 billion gallons of polluted runoff into streams and rivers each year. This water would have otherwise filtered through the soil to recharge aquifers and provide underground flows to rivers, streams and lakes.

The implication of this phenomenon is tremendous -- but the actual impacts on the public's water use vary from city to city. On average, 40 percent of Americans get their water directly from underground sources across the country. Groundwater also supplies, on average, 50 percent of the water in the rivers and lakes that serve everyone else.

The authors conclude that the link between sprawl and drought needs to be examined more closely. The report's results suggest that policies to promote "smart growth" and low-impact development techniques are needed to ensure adequate water supplies and to protect aquatic resources into the future.

The authors conclude that strengthening regional cooperation on planning and concentrating development in already urbanized areas can protect water supplies by slowing the development of open space and containing the spread of impervious surfaces.

Key findings for 18 metropolitan areas can be seen in a table, "Sprawl's impacts on water resources and watersheds" available from American Rivers.

Agriboard Industries Resumes Operation

After closing their doors three years ago, the company that makes a unique straw-based building panel is back in business. Ryan Development Co. L.C. purchased the shuttered Agriboard Industries last year and has resumed operation of their pilot plant in Electra, Texas. The mill uses a heat and extrusion process to form wheat and rice fibers into compressed agricultural fiberboard. Oriented Strand Board is then applied to the outside surfaces to make a structural panel custom fit to residential and commercial plans. Panels are erected with the help of a crane that cuts construction time. The panels have impressive thermal and sound insulating qualities as well as exceptional strength and fire resistance. Agriboard has been used in government projects with the United States Postal Service and General Services Administration, as well as medical, commercial and residential projects. Ron Ryan, owner of Ryan International Airlines, is principal owner and chairman of the board.

Urban Trees Salvaged for High-Value Uses

Scrap wood in the San Francisco Bay Area now has a new place to go. According to a report issued by the California Integrated Waste Management Board (CIWMB) in 1994, nearly 3 million tons of urban wood waste enters the California municipal wastestream annually. Of this amount, 88% was landfilled, while the remaining 12% was diverted. The majority of the urban wood entering the wastestream comes from scrap lumber, pallets, sawdust, tree stumps, logs, branches and twigs. Twenty-two percent of the urban wood waste entering the municipal waste stream originated from the San Francisco Bay region.

Slabs milled from urban salvage await a high-value use at the PAL Tree Recycling Yard.

Protect All Life (PAL) Foundation hopes that its Tree Recycling Yard -- which recently started full operating mode -- will become the first place that people think of to take waste wood, just as recycled paper has become commonplace over the last ten years.

In 1989, the California Legislature adopted AB 939, which created the California Integrated Waste Management Act. The act established aggressive state mandates for waste reduction and laid at the feet of local government a daunting legal challenge: reduce your waste stream by 50% by the year 2000. The Greater Bay Area and in particular, Alameda County, has made considerable progress in reducing its waste stream, bolstered by a supportive constituency and a vast array of programs in the public, private and non-profit sectors.

“The lack of a well-functioning tree yard serving the greater San Francisco Bay Area has forced even the most environmentally sensitive arborists and tree surgeons to pay landfills to add millions of pounds of woody biomass every year to their dumpsites,” according to PAL Foundation Executive Director and co-Founder, Marcus von Skepsgardh. “Regretfully, most lumber currently available on the open market does not come from recycled or salvaged trees, despite the large supply of available trees removed from building sites, parks and public lands throughout the Bay Area resulting from disease, storms or construction projects. Instead, lumber companies cut down live trees and do not take advantage of the large supply of naturally fallen or salvaged trees.”

PAL’s Tree Recycling Yard program has already diverted over 6000 tons of trees and woody biomass form California landfills. Its mission is to promote the highest-end uses of naturally-fallen urban trees through the manufacture and sale of recycled lumber, designer countertops, flooring, decking and other recycled products to wood workers, architects, builders, lumber companies, businesses, and to individuals. PAL mills lumber onsite at its tree yard located in Oakland. In addition, it offers a tree pick-up service to remove felled, limbed trees locally.

PAL’s program has received support from the Alameda County Source Reduction and Recycling Board, San Francisco Department of the Environment, the San Francisco Foundation, the Richard and Rhoda Goldman Fund, the Lisa and Douglas Goldman Fund, and most recently the USDA Forest Service. The tree recycling yard has significant potential for replication on a national and international scale, ultimately leading to a more sustainable global community to be passed on to future generations.

Bush Administration Proposes Changes to Federal Landfill Regulations

According to the Grass Roots Recycling Network, the Bush Administration is attempting to deregulate national landfill standards. It is proposing to create a new rule that would permit most States to waive compliance with most design, operation and cover standards for municipal landfills under the guise of "innovation." GRRN outlines its position on it's Web site and offers an email form to transmit your opinion to the Environmental Protection Agency.

PV Program On Hold

The Sacramento Municipal Utility District (SMUD) has stopped initiating new installations under its popular "PV Pioneer" program. According to SMUD, "industry costs for producing photovoltaic panels have not declined as expected, and there have been some internal budgeting and state funding shortfalls."

The SMUD Board of Directors have added $4.4 million in funds, and may to inject another $1.9 million more if state funding fails to materialize. These funds will allow SMUD to honor existing contracts and will not affect rates or the utility's budget. SMUD is still committed to provide 20 percent of its customer's electricity needs with non-hydro renewable energy by 2011.

Institute Publishes Steel Framing Standards

The American Iron and Steel Institute (AISI) has published design and construction standards for cold-formed steel framing. The newly approved standards are the first set of documents that have received approval from the American National Standards Institute (ANSI). ANSI is a private, non-profit organization that administers and coordinates the U.S. voluntary standardization and conformity assessment system. It is also approved in Canada by the Canadian Standards Association (CSA), and approved in Mexico by CANACERO.Documents include:

  • Standard for Cold-Formed Steel Framing-Prescriptive Method for One and Two Family Dwellings.
  • Standard for Cold-Formed Steel Framing - Truss Design
  • Standard for Cold-Formed Steel Framing - General Provisions
  • Standard for Cold-Formed Steel Framing - Header Design

All may be purchased on AISI's website.

Aerogels Promise Strong, Lightweight Building Materials

Researchers say they have developed the world's strongest, lightest solids. Called aerogels, the sturdy materials are a high-tech amalgam of highly porous glass and plastic that is as light as air. The materials could also be used for better window insulation, longer-lasting tires, and lighter, safer aircraft and space vehicles, they say.

A study describing these materials appeared in the September 12 print issue of Nano Letters, a peer-reviewed journal of the American Chemical Society.

"We took the lightest material available and made it 100 times stronger, giving us the strongest, lightest material known to man," says Nicholas Leventis, Ph.D., a chemist with the University of Missouri-Rolla and a chief author of the paper. "Our material appears promising for practically any application that requires lightweight, strong materials."

Aerogels were originally developed in the 1930s. They remained a curiosity until the 1960s, when scientists began to consider them as a medium for storing liquid rocket fuel. The first aerogels were made of silica and had a chemical composition identical to glass. Although lightweight, aerogels have, until now, been extremely brittle and have absorbed moisture easily, which limited their practical applications.

In an effort to improve upon the strength of these materials, Leventis and his associates decided to weave together strings of tiny particles of silica (glass) with polyurethane (a plastic). The resulting material, however, still remained too brittle.

The researchers then decided to cross-link the strings of the nano-sized glass particles with polyisocyanate, one of the two components of polyurethane. Like earlier aerogels, the resulting materials were almost as light as air. But the new chemical approach resulted in aerogels that were 100 times more resistant to breakage, and almost totally insensitive to moisture compared with the original version of aerogels made of plain silica.

Aerogels are also known for their high resistance to heat transfer, making them promising as insulating materials. In the near future, the new aerogel nanocomposites will probably appear in insulated windows, refrigerators and thermoses, Leventis predicts.

Solar Decathlon Draws 14 Teams to Compete

College students around the country are completing 14 custom-designed solar-powered homes, and soon each house will be transported to the nation's capital for the U. S. Department of Energy's (DOE) first-ever Solar Decathlon.

The Solar Decathlon is a team competition among universities to design and build the most energy-efficient, solar-powered homes, being held on the National Mall in Washington, D.C., from Sept. 26 to Oct. 5. To win the Solar Decathlon, a team must blend aesthetics and modern conveniences with maximum energy production and efficiency.

Each house, limited to roughly 500 square feet for purposes of the competition, will be judged on 10 criteria to determine which most efficiently employs solar energy for heating, cooling, hot water, lighting, appliances, computers and charging an electric car. The teams will compete in the 10 contests simultaneously.

A jury of world-renowned architects will evaluate the attractiveness, livability and effectiveness of each home's design, while experts from DOE and National Renewable Energy Lab (NREL) will measure each home's energy production and use.

The Solar Decathlon gives architecture and engineering students practical experience with the design and construction of solar powered, energy efficient buildings. DOE provided each team with a $5,000 stipend toward the construction of their solar house. The teams are raising the rest of the money they need to design, construct and transport the houses to Washington, D.C.

Sponsors of the Solar Decathlon, in addition to DOE, include BP Solar, The Home Depot, EDS, the American Institute of Architects (AIA) and DOE's National Renewable Energy Laboratory (NREL).

CEE Launches Motor Decisions Matter Campaign

You don't think much about motors, until they breakdown or need to be replaced. And then limiting downtime is often more important than saving energy. But the energy used by motors is so significant that it makes sense to choose them carefully.

Motor energy costs can exceed $1 million annually in large industrial plants; in steel plants it can exceed $6 million. According to the U.S. Department of Energy, greater attention to motor system management can reduce these costs by 18 percent while also boosting productivity, reliability and profitability.

By replacing failed motors quickly (and at the lowest first cost), many industrial managers don't get the maximum benefit from their motor decisions. In fact, few companies today are aware of this opportunity; less than 10 percent have written specifications for motor purchases or repair.

The Motor Decisions Matter campaign, recently launched by the Consortium for Energy Efficiency, will highlight the benefits of sound motor management to corporate managers and plant personnel. The campaign will encourage customers to work through their local motor repair center/distributor or utility representative to develop solutions. They will provide detailed guidance on motor management and relevant motor-efficiency tools and resources. The goal is to help industrial and commercial customers use life-cycle costing methods to determine whether motors should be repaired or replaced before they fail and when to install energy-efficient motors.

Motor Decisions Matter promotes system efficiency by encouraging industrial and commercial customers to evaluate their motor repair and replacement options, and to develop a motor management plan before motors fail.

Wisconsin Engineers Make Hydrogen from Biomass

In the search for a nonpolluting energy source, hydrogen is often cited as a potential source of unlimited clean power. But hydrogen is only as clean as the process used to make it. Currently, most hydrogen is made from fossil fuels like natural gas using multi-step and high-temperature processes.

Now, chemical engineers at the University of Wisconsin-Madison have developed a new process that produces hydrogen fuel from plants. This source of hydrogen is non-toxic, non-flammable and can be safely transported in the form of sugars.

Writing in the August 29 issue of the journal Nature, research scientist Randy Cortright, graduate student Rupali Davda and professor James Dumesic describe a process by which glucose, the same energy source used by most plants and animals, is converted to hydrogen, carbon dioxide and gaseous alkanes with hydrogen constituting 50 percent of the products. More refined molecules such as ethylene glycol and methanol are almost completely converted to hydrogen and carbon dioxide.

"The process should be greenhouse-gas neutral," says Cortright. "Carbon dioxide is produced as a byproduct, but the plant biomass grown for hydrogen production will fix and store the carbon dioxide released the previous year."

Glucose is manufactured in vast quantities -- for example, in the form of corn syrup -- from corn starch, but can also be made from sugar beets, or low-cost biomass waste streams like paper mill sludge, cheese whey, corn stover or wood waste.

While hydrogen yields are higher for more refined molecules, Dumesic says glucose derived from waste biomass is likely to be the more practical candidate for cost effectively generating power.

"We believe we can make improvements to the catalyst and reactor design that will increase the amount of hydrogen we get from glucose," says Dumesic. "The alkane byproduct could be used to power an internal combustion engine or a solid-oxide fuel cell. Very little additional energy would be required to drive the process."

Because the Wisconsin process occurs in a liquid phase at low reaction temperatures (227 degrees C., 440 degrees F.) the hydrogen is made without the need to vaporize water. That represents a major energy savings compared to ethanol production or other conventional methods for producing hydrogen from fossil fuels based on vapor-phase, steam-reforming processes.

In addition, the low reaction temperatures result in very low carbon monoxide (CO) concentrations, making it possible to generate fuel-cell-grade hydrogen in a single-step process. The lack of CO in the hydrogen fuel clears a major obstacle to reliable fuel cell operation. CO poisons the electrode surfaces of low-temperature hydrogen fuel cells.

At current hydrogen yields, the team estimates the process could cost effectively generate electrical power. That, according to the Wisconsin researchers, assumes a low-cost biomass waste stream can be efficiently processed and fed into the system.

To be truly useful, the team says several process improvements must first be made. The platinum-based catalyst that drives the reaction is expensive and new combinations of catalysts and reactor configurations are needed to obtain higher hydrogen yields from more concentrated solutions of sugars.

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