Nationwide, 60 million tires are converted into aggregate each year, and 13 states allow it as a lightweight fill for highway embankments. Photo: Kleinfelder
Nationwide, 60 million tires are converted into aggregate each year, and 13 states allow it as a lightweight fill for highway embankments. Photo: Kleinfelder
Acting EPA Region 7 Administrator William Rice (right) presents the Combined Heat and Power Award to (from left) Scott Lucas of Macon Missouri Utilities and John Grotzinger of the Missouri Joint Municipal Electric Utility Commission. Photo: EPA Region 7
Acting EPA Region 7 Administrator William Rice (right) presents the Combined Heat and Power Award to (from left) Scott Lucas of Macon Missouri Utilities and John Grotzinger of the Missouri Joint Municipal Electric Utility Commission. Photo: EPA Region 7
Field crews test voice recognition

Inspecting the 24,000 electronic pull boxes owned by Clark County, Nev., takes one-fourth the time it used to.

Former Public Works Systems Administrator Jim Houser used AccuSpeechMobile from Vangard Voice Systems to add voice capability to employees' mobile lap-tops, then paid $9,000 for the company to develop an interface with the department's ESRI ArcGIS database.

“We went out into the field, we put on the headsets, and we ran through the program,” Houser says. When vocally responding to voice-generated prompts, inspectors spent an average of 4 minutes — not the usual 18 — to fill out 10 or so fields on the laptop-resident form.

“Speech will throw all your productivity scales out the window,” Houser says. “It'll bring to the table the same thing that GIS brought to asset management.”

Houser urges interested infrastructure departments to jump in now, while vendors are trying to break into the government market. Houser budgeted $50,000 to buy 20 licenses so the technology can be used to update 92 miles of storm drains.

Crusade against chromium is justified

After a decade of debate, federal scientists say that the contaminant featured in the 2000 docudrama Erin Brockovich does indeed cause cancer.

National Toxicology Program scientists report that a two-year study “clearly demonstrates” that hexavalent chromium, also known as Chromium 6, is carcinogenic in drinking water. The chemical is used to produce stainless steel, manufacture textiles, and preserve wood.

California, where the events depicted in the movie took place, is expected to propose a new health guideline as a result. The groundwater of a town near a Pacific Gas and Electricity facility that used hexavalent chromium to counter rust in cooling towers contained concentrations of up to 580 ppb, more than five times the national drinking water standard of 100 ppb for total chromium compounds.

Rubber meets the roadside

Cities and counties can get grants of up to $500,000 a year from the California Integrated Waste Management Board to use rubberized asphalt in hot mixes and chip seals. But if they use tire-derived aggregate for another application, the board gives it away for free.

That's one reason the Sonoma County Department of Transportation and Public Works uses the material to control erosion along 1,300 miles of road. After repairing a 75-foot slide along 1,000 feet of rural road last year, the department recently saved $300,000 on a project that consumed 6,400 cubic yards.

“The use of rubber aggregate in the design of the repair doubles the safety factor due to the light weight,” says Deputy Director Tom O'Kane. “The material is easy to spread, compact, and cover. As long as there's a supply of chipped tires, we'll use it in these cases.”

The aggregate ranges in size from 25 millimeters to 300 millimeters and costs $25 to $55/ton. It's highly permeable and absorbs vibrations well, making it an attractive alternative to building retaining walls or importing volcanic rock.

Energy exchange cuts greenhouse gases

An energy-recovery-and-reuse system developed by the Missouri Joint Municipal Electric Utility Commission and a private fuel producer has earned the EPA's Energy Star Combined Heat and Power (CHP) Award.

The commission leased land from the POET Biorefining ethanol plant in Laddonia, Mo., to install a 20,000-hp natural gas-fired combustion turbine that generates up to 13 MW of electricity for operations.

Designed by Shafer, Kline, and Warren Inc. and centered on a Solar Turbines product, the system requires 26% less fuel than typical onsite thermal generation options and has an operating efficiency of 67%. “The electricity generated by the gas turbine helps keep electric rates stable for municipal electric customers throughout Missouri,” says John Grotzinger, COO of the commission, whose members provide electricity to 347,000 retail customers.

The program recognizes projects that use at least 5% less fuel than state-of-the-art, comparable separate heat and power generation.

Proposed accessibility rule change postponed

In response to a request by the Obama administration, the U.S. Department of Justice has withdrawn its final draft of rule changes to Titles II and III of the Americans with Disabilities Act (ADA).

The new rules would allow state and local governments to use the International Building Codes instead of the Americans with Disabilities Accessibility Guidelines to ensure facilities meet accessibility requirements.

It also proposes that standards be expanded to playgrounds and existing recreational facilities such as swimming pools, boating facilities, and golf courses; dormitories; arenas; and court facilities, which would have to provide a ramp or lift for raised witness stands.

The final rule isn't expected until late this year at the earliest. In the meantime, public agencies must continue to follow existing regulations, including the ADA Standards for Accessible Design.

Chinese turn e-waste into asphalt modifier

Old circuit boards can be recycled through a process that separates toxic heavy metals from polychlorinated biphenyl, leaving behind a fine, metal-free powder that can be added to virgin polymer to make asphalt modifier.

What's more, the recycled polymers are just as effective as virgin polymers.

“The nonmetals consist of thermosetting polymers, fiberglass, brominated flame retardants, and other additives,” says the report from two universities in Shanghai. “Thermosetting polymers cannot be re-melted or reformed because of their network structure,” which makes them strong additives.

The report goes on to note that “the use of waste polymers as asphalt modifiers is considered a rather new and interesting way of modification because it involves two important aspects: waste material utilization and asphalt property enhancement. In our previous research, the nonmetals were reused as reinforcing fillers … proving that the nonmetals can be a good filler for different polymer matrixes.”

In 2007 Americans threw out 2.2 million tons of electronics. Nearly three-quarters of heavy metals found in landfills are from such waste, and more than 70% of a circuit board is plastic.

Private-sector salaries drop as backlogs dwindle

The shrinking construction market spurred 21% of architecture, engineering, and environmental consulting firms to cut principals' pay in 2008, according to a survey conducted by ZweigWhite.

The business management services firm reports a $5,000 drop in principals' salaries since 2007, when median base salary reached a 10-year high of $135,000. The median principal base salary in 2006 was $130,000.

As firms continue to react to the market's contractions late last year, senior-level salaries may drop even lower.

“Like many economic indicators, these statistics reflect activity and conditions from several months ago,” says ZweigWhite CEO and President Ian Rusk. “Many firms were carried through the early months of the recession by healthy backlogs, and are just now feeling the real cash flow impact of the downturn. We've heard from more firms looking to adjust compensation of senior management in the last two months than we did all year.”

Fleet expands list of alternative fuels

Fifteen police SUVs owned by Hoover, Ala., are the first in the nation to be fueled by “cellulose-based ethanol.”

Since last year public works has sent ground-up tree branches to Gulf Coast Energy Inc., a 2-year-old alternative-fuel manufacturer, to experiment with at a demonstration plant. The company wants to build three commercial plants throughout the state that are expected to produce 200 gallons of ethanol for every ton of wood chips. When they're up and running, the city could save $100,000 in tipping fees to landfill the 2,000 tons of wood waste it collects each year.

“Our goal all along has been to be cellulosic,” says Fleet Management Director David Lindon, whose operation converts used cooking oil into biodiesel for 186 trucks and pieces of equipment and maintains 196 more vehicles that run on ethanol. “Corn's not the answer because you can't raise enough to fuel the country. Once that plant is up, we could be self-sufficient within 18 months.”

General Motors has authorized the city to use the cellulose-based ethanol on its police fleet of flexible-fuel 2005 Chevrolet Tahoes. “There was absolutely no difference in performance from corn-based ethanol,” says Lindon.

The process that converts cellulose — gasification — has been used mainly on coal. In this case, the wood waste is ground and fed into a dryer. It's subjected to intense heat that forms a synthetic gas by separating the carbon monoxide, carbon dioxide, and hydrogen. A microorganism introduced to the process then ingests the gas and produces ethanol and water.