The Septic System Solution Will Be A Costly Blunder
Richard H. Bennett Ph.D.
The State of Hawai‘i and its Department of Health (HDOH) is attempting to address the problem of human waste cesspits on the islands. Myopically, the Health Department is advocating conversions to Septic Systems (SS) as if they are the solution to the problem. The French invented septic systems in the 1800ʻs to dispose of the human waste to the ground. Any notion that significant attenuation of nutrients or pathogens occurs in SS arises from myth, not science.
Today, the scientific basis of septic drain field performance is poorly researched and impossible to predict in general, given the number of site-specific and operational variables. Just the same, contemporary science very clearly reveals SS offer no significant or cost-effective improvements over cesspits.
The SS myths promoted by staff and of HDOH documents on its website, loom large in the public discourse. They allege that septic systems are vastly superior to cesspits based upon unsubstantiated numerical data. This assertion is contradicted by an extensive research review as reported by McCray in 2010 (1). Septic system advantages are slight at best and will fail to protect the quality of the ground waters and oceans from waste nutrients and potential pathogens.
The misleading and unsubstantiated DOH septic system data is a web-published paper entitled, Onsite Wastewater Treatment Survey and Assessment Survey (OWTS) 2008. The source of this propaganda is only that of the HDOH and not the UH Water Resource Research Center as erroneously reported on the document.
The HDOH information is in stark contrast with data from three published scientific papers, one of which was conducted with Hawaiian soils by WRRC scientists in 1980 (2). All the studies used lysimeters to collect the actual leachate that flowed through the soil disposal sites. This real data from Hawaiian sites is very different and far less magically optimistic than the unsubstantiated HDOH report.
In great contrast to the OWTS, in the field study, total Nitrogen was 14 to 60 times greater. The Fecal Coliform data (a pathogen indicator measurement) is the most troubling. The 2008 “Onsite Survey” data suggests that septic disposal soil systems will cause a ten million reduction in the Fecal Coliform (FC). In the field research, on such disposal, FC numbers ranged from hundred thousand to ten million bacteria per 100 ml of leachate. The data represents a considerable discrepancy and further invalidates the HDOH claim.
HDOH also fails to evaluate virus movement in septic system leach fields. Existing microbial transport models that are pathogen-specific were not employed. Moreover, bacteria of any class are not validated models for virus movement in soils. Viruses are 1/100th the size of Bactria and can rapidly move with the leachate in soils and rock. Because virus typically have a very low MID (minimal infective dose) a few virus ingested during recreation in contaminated waters can cause disease.
The good news from contemporary human microbiome studies, reveals for the first time that healthy people do not shed pathogens in their feces as a matter of course (3). The lack of virus explains why there is a not multi-person disease outbreak among ocean users in areas where sewage contamination is routine. That situation profoundly changes when persons are ill with an enteric virus. The most common virus in ground and seawater is the Norovirus, aka Stomach Flu. Diseased persons shed hundreds of trillion viruses daily for about 7 to 15 days after infection begins.
Sophisticated site-specific science-based models for septic nutrient loading to the environment have existed for years. The models are not utilized in the rationale for the formation of the proposed statewide policies that address nutrient discharge to the nearshore waters. A few hundred feet set back from septic systems to wells or shores will have negligible influence on the nutrient movement to the water.
Failing to recognize the merits of environmental science and failing to incorporate this information in the proposed solutions and rules, is inexcusable.
We need to recognize that nitrogen pollution of our nearshore reef ecology synergistically damages corals when combined with increasing temperatures and acidity caused by anthropogenic atmospheric carbon dioxide, aka Global Warming. Research demonstrates that we can reduce the damage done to the coral by limiting nutrient flows to the sea. In the nearshore area, the N and P leaching is detrimental to coral health and coastal ecosystems. It promotes marine algae that damage the reef and cloud the waters. These reef ecosystems have a 300 million dollar per year value for the local economies. This imperative and opportunity cannot be dismissed, given governments obligation to the “public trust doctrine” and our livelihoods.
In summation, the rush to address the cesspit problem, we must not be done without a scientifically verifiable set of solutions addressing the very complex geologic, hydrologic and climatic conditions, unique to Hawaii. Otherwise, we could spend hundreds of millions of public and private dollars, achieve little environmental and public health protection while betraying the public trust.
Modern waste systems at the home and neighborhood scale exist in many locations in the mainland and the world. The need to incorporate this technology cannot be dismissed, without justifications. Many of these systems meet ANSI standards for nitrogen removal and enhanced treatment. Some systems can even produce water of drinking quality!
It is not in our best interest to allow the gap between science and policy to exceed the current chasm. The cost to health and the economy is too great. We need to be assured that policies and investments for wastewater management are indeed "science-based" and ensure the protection of the environment and public health.
 McCray, J. E., et al. "Quantitative Tools to Determine the Expected Performance of Wastewater Soil Treatment Units." Water Environment Research Foundation, DEC1R06 (2010).
 Tasato, Gary T., and Gordon L. Dugan. Leachate quality from lysimeters treating domestic sewage. Water Resources Research Center, University of Hawaii, 1980.
 Huttenhower, Curtis, et al. "Structure, function and diversity of the healthy human microbiome." Nature 486.7402 (2012): 207.
Dr. Richard Bennett is a semi-retired academic environmental scientist with over 30 years experience with waste and water science and public policy. In the 1990ʻs he worked closely with the cities of Petaluma and Santa Rosa, CA on wastewater reclamation. Today those cities irrigate thousands of acres of farmland instead of discharging the water to rivers and oceans. Currently, Dr. Bennett is the Chair of the Hawaii County Environmental Management Commission. His personal goal is to reclaim all wastewater and eliminate discharges to the ground and thus the sea.
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