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Clean Water without Mountains of Sludge
26th December 2010
By Alan M. Weiss
Four years after Kern County, California voters overwhelmingly voted to ban the use or dumping of sewage sludge on the unincorporated areas of the county, and even after the U.S. Supreme Court on June 1, 2010 essentially tossed out the Constitutional arguments against the ban, Kern County’s legal battle with the City of Los Angeles is far from over.
Kern County officials expect Los Angeles to continue its legal challenge in the state or federal courts. Meanwhile, LA continues to dump its sludge in Kern County and legal costs for the tax and rate payers continue to mount.
The implications and potential legal impact of this dispute could extend to every city and town in the nation, and it is being watched closely by water departments and municipal officials nationally. Perhaps the biggest disappointment in this saga is the missed opportunity (so far) to rethink how cities in California and nationwide process waste water.
The rudimentary sedimentation system that LA and most cities use is basically unchanged from 100 years ago. The sewage going through the systems, however, has become loaded with ever more toxic chemicals, heavy metals, and potentially dangerous bacteria and viruses.
What comes out is not-very-clean liquid effluent and sludge (euphemistically called, bio-solids). The contaminated effluent gets dumped into our oceans, rivers, and streams and the residual sludge gets dumped on agricultural land and other open areas.
The Kern County law, known as Measure E, was approved in 2006 to block shipments from Southern California of more than 450,000 tons a year of sludge to Green Acres, a farm Los Angeles bought in 1999 for about $15 million. The sludge is tilled into the 4,700-acre farm’s soil to fertilize crops, including corn.
Farmers and agri-businesses like sludge because it is cheap fertilizer, but there is much debate about the potential health hazards related both to the long-term use and the actual application of this stuff. There are credible experts and organizations on both sides of the issue. The debate rages on, nevertheless, because there are no long-term studies showing whether there are adverse health effects from the long-term use of sludge for fertilizer.
In the absence of conclusive proof either way, we ought to be focusing on the elimination of sludge, rather than learning to live with it. Why gamble that all those toxic chemicals and lethal organisms really won’t hurt us in the long run, even if they do find their way into the foods we eat and the water we drink?
Most sewage treatment experts in L.A. and across the country will argue that there is no alternative to sludge – this is the inevitable by-product of the water treatment systems that have served us well for more than a century.
In fact, however, there are alternative methods for wastewater treatment that produce no sludge. One of these even produces potable-quality effluent.
Ironically, one ‘green’ technology for sludge-free water processing originally was developed in Texas and Louisiana for the oil and gas industry – hardly an industry normally associated with ‘green’ anything. The industry needed sludge-free water processing systems for its off-shore oil rigs, and the technology was developed for that purpose.
Oil and gas industry biologists developed an aerobic biological treatment referred to as “extended aeration – activated sludge” in which air flow and bacteria digest sewer sludge. These systems, while mostly used in the oil and gas industry achieved some limited use for certain land-based institutions.
The systems, while reducing the sludge substantially, still provided an effluent that was soaked with chlorine – which creates carcinogens — to kill bacteria and created a hazardous chemical discharge.
In the late 1990s, my company, Global Water Group, Inc., combined the waste processing methodology from the oil and gas industry with proprietary purification and recycling processes to create a genuinely “green” wastewater system – potable-quality effluent, no chlorine, and no sludge.
Global uses the aerobic digester with “extended aeration activated sludge” and a super-charged environment to promote digestion of the sewage by bacteria. Global’s proprietary wastewater treatment unit, however, cuts the processing time in half, and unlike conventional treatment plants, Global’s process generates virtually no sludge.
The effluent from the Global digester component flows into the recycling component, which removes remaining suspended solids down to 5-microns and then recycles them back to the digestive process of the wastewater treatment.
All remaining effluent flowing through the recycler is processed through Global’s proprietary LS3 water purification component. There, all parasites are removed; hazardous chemicals are removed; and finally, through ultra-violet light, all the remaining bacteria (e-coli) and viruses are killed or neutralized. This process produces highly purified water available for any potable or non-potable use.
Global Water’s system is modular and easily scalable. It is the model for future municipal systems. The point is this: cities today can, in fact, have water processing systems that produce no sludge and reusable water.
Ordinary citizens can make it politically desirable or imperative for their public officials to do the right thing without waiting for a crisis: seriously evaluate alternative solutions to the sludge problem now.
The Kern County ban and legal fight can be a catalyst for change, or simply another missed opportunity. Obviously, we can’t replace the old ways overnight, but we can begin to make the transition now by seriously evaluating alternative sludge-free systems under real-world conditions. We don’t have to remain stuck in sludge forever.
Alan M. Weiss is chairman and president of Global Water Group, Inc., Dallas, TX, www.globalwater.com.