Department of Water Resources
A daily compilation of significant news articles and comment
September 22, 2008
4. Water Quality -
EPA decides not to limit chemical in tap water
The
Sewage plant likely to be exempt from federal standards, official says
The
Is Drinking from the Toilet Bowl the
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EPA decides not to limit chemical in tap water
The
The Environmental Protection Agency, under pressure from the White House and the Pentagon, is poised to rule as early as Monday that it will not set a drinking water safety standard for perchlorate, a component of rocket fuel that has been linked to thyroid problems in pregnant women, newborns and young children across the nation.
According to a near-final document obtained by the Washington Post, the EPA's "preliminary regulatory determination" - which was extensively edited by White House officials - marks the final step in a six-year battle between career EPA scientists who advocate regulating the chemical and White House and Pentagon officials who oppose it. The document estimates that up to 16.6 million Americans are exposed to perchlorate at a level many scientists consider unsafe; independent researchers, using federal and state data, put the number at between 20 million and 40 million.
Some perchlorate occurs naturally, but most perchlorate contamination in
The new EPA proposal - which assumes the maximum allowable perchlorate contamination level is 15 times above what the EPA suggested in 2002 - was heavily edited by officials of the White House Office of Management and Budget, who eliminated key scientific passages and asked the EPA to use a new computer modeling approach to calculate the chemical's risks.
"They have distorted the science to such an extent that they can justify not regulating" the chemical, said University of Massachusetts Professor Robert Zoeller, an endocrinologist who specializes in thyroid hormone and brain development, and who has a copy of the EPA proposal. "Infants and children will continue to be damaged, and that damage is significant."
In a statement Sunday, the EPA's assistant administrator for water, Benjamin Grumbles, said that "science, not the politics of fear in an election year, will drive our final decision."
The Senate Environment and Public Works Committee, chaired by Barbara Boxer, D-Calif., has endorsed legislation requiring the EPA to set a standard for the chemical and to monitor perchlorate in tap water. On Sunday, Boxer lambasted the agency for refusing to establish a federal exposure standard.
"Perchlorate has been a serious, persistent and widespread problem which threatens the health of our families, especially our children," Boxer said. "For the Bush EPA to walk away from this problem and shrug off this danger is, in my view, unforgivable and immoral."
Federal, state and independent scientists have differed over the years as to what represents an acceptable dose of perchlorate in drinking water, though all have set the bar higher than the nonmandatory level in the EPA's new proposal. In January 2002, the EPA issued a draft risk assessment finding that 1 part per billion should be considered safe; last year
In the EPA's proposed rule, the administration assumes that perchlorate contamination of 15 parts per billion is safe. But its regulatory document states that between 16,000 and 28,000 pregnant women and between 900,000 and 2 million Americans overall could be exposed to higher levels.#
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2008/09/22/MNO8132AR6.DTL
Sewage plant likely to be exempt from federal standards, official says
The
By Mike Lee, STAFF WRITER
Although the official announcement is weeks away, California's top water-quality official for this region said San Diego seems poised to receive a waiver that will allow it to keep running its main sewage treatment plant below federal standards.
The Clean Water Act requires sewage to be processed at the “secondary” level, which removes more solids and other pollutants. In the entire nation, no facility as big as the Point Loma Wastewater Treatment Plant still operates without at least a plan to attain the secondary threshold.
Environmental groups are pressuring
But Mayor Jerry Sanders said the retrofitting cost – which city officials said could reach $1.5 billion – is unnecessary because the current plant doesn't harm the marine ecosystem.
“My assumption is that the city is likely going to operate with the waiver for the next five years and the reissued permit will reflect that. I haven't heard anything . . . to cause me to think otherwise,” said John Robertus, head of the San Diego Regional Water Quality Control Board, which is part of a statewide regulatory system.
His agency has ample records tracking many years of discharges from the Point Loma plant, Robertus said, “and there isn't a regulatory push by the regional board to go to secondary.”
Robertus and his team are working with the U.S. Environmental Protection Agency to review
Alexis Strauss, director of the water division at the EPA's office in
She expects the EPA to issue a tentative ruling in November, then gather public input during a hearing early next year.
“We are not close yet to making an internal recommendation about whether (
Late last year, environmental attorney Marco Gonzalez of the Coast Law Group in Encinitas said the city's request for another waiver means “we are moving toward litigation.”
This week, he said it was premature to speculate about whether conservationists would sue to try to block the third exemption.
“We can't commit to anything until we conclude negotiations, see what the agencies say and conclude work with our experts,” Gonzalez said.
He added that
http://www.signonsandiego.com/news/metro/20080920-9999-1m20loma.html
Is Drinking from the Toilet Bowl the
Before I left
A day after mopping, I gazed balefully at my hotel toilet in
Opened in January, the Orange County Groundwater Replenishment System is the largest of its type in the world. It cost $480 million to build, will cost $29 million a year to run and took more than a decade to get off the ground. The stumbling block was psychological, not architectural. An aversion to feces is nearly universal, and as critics of the process are keen to point out, getting sewage out of drinking water was one of the most important public health advances of the last 150 years.
Still,
Factor in Southern California's near chronic drought, the county's projected growth (another 300,000 to 500,000 thirsty people by 2020) and the rising cost of importing water from the Colorado River and from Northern California (the county pays $530 per acre-foot of imported water, versus $520 per acre-foot of reclaimed water), and rebranding sewage as a valuable resource became a no-brainer. With the demand for water growing, some aquifers dropping faster than they're replenished, snowpacks thinning and climate change predicted to make dry places even drier, water managers around the country, and the world, are contemplating similar schemes.
While
The central message was health and safety, but the persuaders didn't skimp on buzz phrases like "local control" and "independence from imported water." Last winter, the valve between the sewage plant and the drinking-water plant whooshed open, and a new era in
When I visited the plant, a sprawl of modern buildings behind a concrete wall, in March, Wildermuth, in a blue sport coat and bright tie, acted as my guide. "Quick!" he shouted at one point, mounting a ledge and clinging to the rail over a microfiltration bay. "Over here!" I clambered up just as its contents finished draining from the scum-crusted tank. The sudsy water, direct from the sewage-treatment plant, was the color of Guinness. "This is the most exciting thing you'll see here, and I didn't want you to miss it," he said.
Wildermuth went on to explain what we were looking at: inside each of 16 concrete bays hangs a rack of vertical tubes stuffed with 15,000 polypropylene fibers the thickness of dental floss. The fibers are stippled with holes 1/300th the size of a human hair. Pumps pull water into the fibers, leaving behind anything larger than 0.2 microns, stuff like bacteria, protozoa and the dread "suspended solids."
The excitement and the bubbles were backwash: every 21 minutes, air is injected into the microfibers to blast them clean. The schmutz goes back to the sewage-treatment plant, and the cleaner water, now the color of chamomile tea, is pumped toward reverse-osmosis filters in another building. Before we saw that process, Wildermuth led me underground to inspect several enormous pumps and pipes large enough to crawl through.
I noted that everything was clearly labeled and scrupulously clean. Then it dawned on me: reassurance was the reason we'd taken the detour. We followed the pipes up to a sunlit, metal-clad building where the water, now dosed with an antiscalant and sulfuric acid to lower its pH, was forced at high pressure through hundreds of white tubes filled with tightly spiraled sheets of plastic membranes.
Reverse osmosis, Wildermuth says, stops cold almost all nonwater molecules (things like salts, viruses and pharmaceuticals). The stuff that's removed is washed back to a pipe that discharges into the ocean. The filtered water, now known as permeate, moves one building over, where it's spiked with hydrogen peroxide, a disinfectant, and then circulated past 144 lamps emitting ultraviolet light.
"Destruction of compounds through photolysis," Wildermuth said, nodding. Anything that's alive in this water can no longer reproduce.
Strolling back through the campus, Wildermuth took me to a three-part demonstration sink with faucets streaming. The basin on the right contained reverse-osmosis backwash: it was molasses black, topped with a rainbow slick of oil. "Don't touch," Wildermuth warned as I leaned in for a better look at the ocean-bound rejectamenta.
The middle basin contained the chamomile water from microfiltration. And on the left was the stuff
Finally it would enter a massive purple pipe, which dives into the ground inside a nearby pump house and reappears 13 miles to the north, in
The reservoir is a prosaic ending for a substance that's been through the glitziest of technological wringers, transformed from sewage to drinking water only to be humbly redeposited into the earth. This final filtering step isn't necessary, strictly speaking, but our psyches seem to demand it.
To understand the basics of contemporary water infrastructure is to acknowledge that most American tap water has had some contact with treated sewage. Our wastewater-treatment plants discharge into streams that feed rivers from which other cities suck water for drinking. By the time
That's the good news. After heavy rains, many cities discharge untreated sewage directly into waterways -- more than 860 billion gallons of it a year, according to the Environmental Protection Agency.
However -- and this is where we can take solace -- the sewage is massively diluted, time and sunlight help to break down its components and drinking-water plants filter and disinfect the water before it reaches our taps. The E.P.A. requires utilities to monitor pathogens, and there hasn't been a major waterborne-disease outbreak in this country since 1993. (Though there have been 85 smaller outbreaks between 2001 and 2006.)
So confident are engineers of so-called advanced treatment technologies that several communities have been discharging highly treated wastewater directly into reservoirs for years.
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Environmentalists, river advocates and
As we deplete the earth's nonrenewable resources, like oil and metals, the one-way trip from raw material to disposed and forgotten waste makes less and less sense. Already we recycle aluminum to avoid mining, compost organic material to avoid generating methane in landfills and turn plastic into lumber. As it becomes more valuable, water will be no different.
"We have to treat all waste as a resource," Conner Everts, executive director of the Southern California Watershed Alliance, says. "Our water source, hundreds of miles away, is drying up. If the population is growing, what are our options?"
Water conservation could take us a long way, as would lower water subsidies for farmers. But sooner or later, stressed-out utility managers come back to the same idea: returning wastewater to the tap. The process isn't risk-free. Some scientists are concerned that dangerous compounds or undetectable viruses will escape the multiple physical and chemical filters at the plant. And others suggest that the potential for human error or mechanical failure -- clogged filters or torn membranes that let pathogens through, for example -- is too great to risk something as basic to public health as drinking water.
Recycled water should be used only as nondrinking water, says Philip Singer, the Daniel Okun Distinguished Professor of Environmental Engineering at the University of North Carolina. "It may contain trace amounts of contaminants. Reverse osmosis and UV disinfection are very good, but there are still uncertainties."
And then there are those whose first, and final, reaction is "yuck."
"Why the hell do we have to drink our own sewage?" asks Muriel Watson, a retired schoolteacher who sat on a
"It's not the sun and the sky and a roaring river crashing into rocks" -- nature's way of purifying water. "It's just equipment."
The
Not only is more effluent entering the river, a consequence of population growth, but as the county develops and paves more surfaces, rainwater runs off the earth faster, sluicing into the river channel before it can sink into the earth and replenish aquifers. To capture and clean that water, the Orange County Water District has gone into hyper-beaver mode on the river. Twenty miles upstream from
Returned to the main channel, the water wends around T- and L-shaped berms that slow the water and maximize its contact with the river bottom. Gates and sluiceways then shunt the water into nine man-made ponds and pits. The goal is to get more water into the county's groundwater basin, a 350-square-mile, 1,500-foot-deep bathtub of sand and gravel layers, which act as natural scrubbers. The system upriver -- using gravity and gravel -- and the system in
It's one of the many pardoxes of indirect potable reuse that the water leaving the plant in
If everything in the
But once the
In other words, nature messes up the expensively reclaimed water. So why stick it back into the ground?
"We do it for psychological reasons," says Adam Hutchinson, director of recharge operations for the water district. "In the future, people will laugh at us for putting it back in, instead of just drinking it."
Psychologists and marketers have spent a lot of time trying to figure out what makes a product, or a process, seem natural. Obviously, framing the issue properly is the key to acceptance. "If people connect the history of their water to contamination, you'll get a disgust response no matter how you treat that water in between," says Brent Haddad, an associate professor of environmental studies at the
"But if you enable people to frame out that history by telling them, for example, that 'the clean water has been separated from the polluted water,' they no longer make that connection." We abridge history all the time, Haddad adds. "Think of the restaurant fork that was in the mouth of someone with a contagious disease, the pillow that was underneath people doing private adult things in a hotel bedroom. If you think of it that way, the intermediate steps, like washing with hot water, don't matter."
All water on earth is recycled: the same drops that misted Devonian ferns and dripped from the fur of woolly mammoths are watering us today. From evaporation to condensation and precipitation, the cycle goes on and on. But in the planet's drier regions, where the population continues to rise, we can expect the time between use and reuse to grow ever shorter, with purification, pipes and pumps standing in for natural processes. Instead of sand and gravel filtering our drinking water, microfibers and membranes will do the job; instead of sunlight knocking out parasites, we'll plug in the UV lamps.
You could argue that in coming to terms with wastewater as a resource, we'll take better care of our water. At long last, the "everything is connected" message, the bedrock of the environmental movement, will hit home. In this view, once a community is forced to process and drink its toilet water, those who must drink it will rise up and change their ways.
Floor moppers will switch to biodegradable cleaning products. Industry will use nontoxic material. Factory farms will cut their use of antibiotics. Maybe we'll even stop building homes in the desert.
But these situations are not very likely. No one wants to think too hard about where our water comes from. It's more likely that the virtuosity of water technology will let polluters off the hook: why bother to reduce noxious discharges if the treatment plant can remove just about anything? The technology, far from making us aware of the consequences of our behavior, may give us license to continue doing what we've always done.
The recycled water coming out of the sink at the
Then I reminded myself: no naturally occurring water on earth is absolutely pure. And most everything that's in
It was hot, my throat was parched, and I asked for a refill.#
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