Letters to the Editor
Dear Editor,
Thank you for commenting on golf course water usage and the underreported fact that golf courses are trendsetters in the efficient utilization of water resources (see “Unfairly Accused?” by Carol Brzozowski, ). Golf courses inherently are motivated to irrigate as little as possible to ward off the effects of plant diseases and poor playing conditions that accompany inefficient irrigation. Million-dollar golf course irrigation systems engineered for the highest-possible irrigation co-efficiency are costly not for their ability to over-apply irrigation; rather, they are expensive because of their ability to properly apply water only where it is required and with the minimum amount necessary to avoid plant loss.
Brian Powell, CGCS
Old Chatham Golf Club
Durham, NC
Dear Editor,
There is a serious mis-statement in the article, “Testing Waters... Saving Pipes” by Peter Hildebrandt. Hildebrandt states, “If there happens to be a groundwater contamination, something called natural attenuation will be done.”
This is a horribly misleading assertion because the source and transport—and impact—of contamination of a water-supply aquifer are unique to that aquifer and contaminant(s). In addition, remediation of a contaminated aquifer requires careful characterization of the contaminant(s) and aquifer before selection of the appropriate remediation approach can be made.
Groundwater contamination could be something as serious as a plume of dissolved chlorinated hydrocarbons.
Groundwater contamination could be naturally occurring—like arsenic. If you are chlorinating your well for disinfection, you could be exacerbating your water-quality concerns by changing the geochemistry of the aquifer and releasing arsenic (and other naturally occurring constituents) into your water supply.
Contamination could be due to road salt used during the winter—and then seeping into your aquifer—or nitrates from failing septic systems or agricultural practices. The most common groundwater contaminant in the United States is volatile organic constituents like industrial solvents and dry-cleaning solvents (also known as chlorinated hydrocarbons), but leaky gasoline tanks also contribute petroleum products and other chemicals—such as MTBE—into water-supply wells.
“Something called natural attention” is not something that can be “done.” Natural attenuation is a remediation approach sometimes allowed (permitted) by the appropriate regulatory agency. For example, New Jersey took the lead in permitting natural attenuation in the mid-1980s when the state observed that plumes of groundwater contamination resulting from leaky underground storage tanks at the local gas station were magically “going away.” The geochemistry of the aquifer (oxidation-reduction potential, pH, etc.) coupled with naturally occurring bacteria in the soils would break down the contaminants to their basic elements—carbon and oxygen. In some cases, aquifers could be inoculated with bacteria collected from other plumes to facilitate the chemical breakdown; in other cases, nutrients, such as molasses, would be added to the aquifer to accelerate the process. But in general, it was observed that given time, the plume would naturally biodegrade (this, of course, is always dependent on the concentration within the plume; low concentrations would biodegrade; higher concentrations and “free product” would take thousands of years).
The regulatory agency would require any responsible party requesting natural attenuation as its remediation option to predict how long it would take—and models were developed to provide this prediction. Model input required measurement of the aquifer geochemistry (pH, oxidation-reduction potential, temperature, etc.).
In some interesting cases, where a plume originating from a gasoline station would mingle with a plume originating from a manufacturing facility (petroleum constituents mingling with chlorinated hydrocarbons), the toluene in the gasoline would be a co-metabolite and would accelerate the process.
The natural biodegradation of the chemical within the contaminant plume, coupled with the flow of groundwater that would allow mixing and spreading of the plume (the solution to pollution is dilution) results in what is known as “natural attenuation”—essentially, waiting, watching, and monitoring as the groundwater contaminant “goes away.”
And then in some cases, the end product of the natural attention process would result in a contaminant that is far more dangerous than the original chemical. Some chlorinated hydrocarbons naturally biodegrade down to vinyl chloride, and depending on the geochemistry of the aquifer, that vinyl chloride volatilizes— or sticks around in the water supply. Vinyl chloride causes cancer.
Please do not try to simplify groundwater contaminants—or remediation approaches to that contamination. The topic is complicated and requires a multidisciplinary approach to understand the topic, including chemists, engineers, geologists, and hydrologists. Natural attenuation is least likely to be the remediation option of choice.
Kristine Uhlman, RG
University of Arizona
Water Resources Research Center
Dear Editor,
I recently have enjoyed reading several articles by Peter Hildebrandt in Water Efficiency online, particularly “Desalination: One Way the Lone Star State Will Beef Up Its Water Supply,” and “Reclaiming Water in Cary, NC” .
I am a professional member of the American Society of Irrigation Consultants (ASIC), and we are in the process of planning our 2007 national conference, which is slated for April 28–30, 2007, at the Charleston Riverview Hotel in Charleston, SC. It is my responsibility to line up a speaker to present an hour-long program regarding alternative water supplies for irrigation, and the information Hildebrandt presents in each of these articles aligns with that topic perfectly.
For more information about ASIC, please visit our association’s Web site at www.asic.org.
Doug Macdonald, ASIC
Aqua Engineering Inc.
July-August 2007
Letters to the Editor
Dear Editor,
Thank you for commenting on golf course water usage and the underreported fact that golf courses are trendsetters in the efficient utilization of water resources (see “Unfairly Accused?” by Carol Brzozowski, ). Golf courses inherently are motivated to irrigate as little as possible to ward off the effects of plant diseases and poor playing conditions that accompany inefficient irrigation. Million-dollar golf course irrigation systems engineered for the highest-possible irrigation co-efficiency are costly not for their ability to over-apply irrigation; rather, they are expensive because of their ability to properly apply water only where it is required and with the minimum amount necessary to avoid plant loss.
Brian Powell, CGCS
Old Chatham Golf Club
Durham, NC
Dear Editor,
There is a serious mis-statement in the article, “Testing Waters... Saving Pipes” by Peter Hildebrandt. Hildebrandt states, “If there happens to be a groundwater contamination, something called natural attenuation will be done.”
This is a horribly misleading assertion because the source and transport—and impact—of contamination of a water-supply aquifer are unique to that aquifer and contaminant(s). In addition, remediation of a contaminated aquifer requires careful characterization of the contaminant(s) and aquifer before selection of the appropriate remediation approach can be made.
Groundwater contamination could be something as serious as a plume of dissolved chlorinated hydrocarbons.
Groundwater contamination could be naturally occurring—like arsenic. If you are chlorinating your well for disinfection, you could be exacerbating your water-quality concerns by changing the geochemistry of the aquifer and releasing arsenic (and other naturally occurring constituents) into your water supply.
Contamination could be due to road salt used during the winter—and then seeping into your aquifer—or nitrates from failing septic systems or agricultural practices. The most common groundwater contaminant in the United States is volatile organic constituents like industrial solvents and dry-cleaning solvents (also known as chlorinated hydrocarbons), but leaky gasoline tanks also contribute petroleum products and other chemicals—such as MTBE—into water-supply wells.
“Something called natural attention” is not something that can be “done.” Natural attenuation is a remediation approach sometimes allowed (permitted) by the appropriate regulatory agency. For example, New Jersey took the lead in permitting natural attenuation in the mid-1980s when the state observed that plumes of groundwater contamination resulting from leaky underground storage tanks at the local gas station were magically “going away.” The geochemistry of the aquifer (oxidation-reduction potential, pH, etc.) coupled with naturally occurring bacteria in the soils would break down the contaminants to their basic elements—carbon and oxygen. In some cases, aquifers could be inoculated with bacteria collected from other plumes to facilitate the chemical breakdown; in other cases, nutrients, such as molasses, would be added to the aquifer to accelerate the process. But in general, it was observed that given time, the plume would naturally biodegrade (this, of course, is always dependent on the concentration within the plume; low concentrations would biodegrade; higher concentrations and “free product” would take thousands of years).
The regulatory agency would require any responsible party requesting natural attenuation as its remediation option to predict how long it would take—and models were developed to provide this prediction. Model input required measurement of the aquifer geochemistry (pH, oxidation-reduction potential, temperature, etc.).
In some interesting cases, where a plume originating from a gasoline station would mingle with a plume originating from a manufacturing facility (petroleum constituents mingling with chlorinated hydrocarbons), the toluene in the gasoline would be a co-metabolite and would accelerate the process.
The natural biodegradation of the chemical within the contaminant plume, coupled with the flow of groundwater that would allow mixing and spreading of the plume (the solution to pollution is dilution) results in what is known as “natural attenuation”—essentially, waiting, watching, and monitoring as the groundwater contaminant “goes away.”
And then in some cases, the end product of the natural attention process would result in a contaminant that is far more dangerous than the original chemical. Some chlorinated hydrocarbons naturally biodegrade down to vinyl chloride, and depending on the geochemistry of the aquifer, that vinyl chloride volatilizes— or sticks around in the water supply. Vinyl chloride causes cancer.
Please do not try to simplify groundwater contaminants—or remediation approaches to that contamination. The topic is complicated and requires a multidisciplinary approach to understand the topic, including chemists, engineers, geologists, and hydrologists. Natural attenuation is least likely to be the remediation option of choice.
Kristine Uhlman, RG
University of Arizona
Water Resources Research Center
Dear Editor,
I recently have enjoyed reading several articles by Peter Hildebrandt in Water Efficiency online, particularly “Desalination: One Way the Lone Star State Will Beef Up Its Water Supply,” and “Reclaiming Water in Cary, NC” .
I am a professional member of the American Society of Irrigation Consultants (ASIC), and we are in the process of planning our 2007 national conference, which is slated for April 28–30, 2007, at the Charleston Riverview Hotel in Charleston, SC. It is my responsibility to line up a speaker to present an hour-long program regarding alternative water supplies for irrigation, and the information Hildebrandt presents in each of these articles aligns with that topic perfectly.
For more information about ASIC, please visit our association’s Web site at www.asic.org.
Doug Macdonald, ASIC
Aqua Engineering Inc.