MARANA – Town of Marana Council made a unanimous decision on Tuesday, August 14, 2018 to pursue design and construction of a water treatment facility for each of the two impacted systems in Marana Water found to contain unregulated compounds. This decision was made after evaluating several solutions, including blending alternatives and other water sources. Constructing water treatment facilities in each of the impacted systems was considered to be the most effective solution to providing safe, clean drinking water now and for future development.
Town of Marana Water Director John Kmiec gave a presentation on unregulated compounds found within two of Marana Water’s water systems to Town Council on Tuesday, August 14. After hearing the history of past water quality issues in southern Arizona, descriptions of the compounds found, and learning about possible solutions to address the compounds, Town Council provided direction to staff to return with a presentation showing financial viability for a water treatment facility at the two impacted systems in Marana Water.
Water treatment would require a multi-million dollar capital improvement project for each impacted system to completely remove or destroy the target compounds from the water.
"I think we ought to build a treatment plant," said Councilmember Jon Post. "Marana should develop a water quality standard that sets automatic targets for our Town."
"I do believe this Town needs to provide clean water," said Councilmember Roxanne Ziegler. "I am in favor of getting this done immediately."
"I am in favor of pursuing the most aggressive means of dealing with this, which would be building a treatment plant," said Councilmember Dave Bowen.
"Let's take action so we can move forward with a filtration system," said Councilmember John Officer.
"I'm glad we're looking at redundancies," said Councilmember Patti Comerford in reference to a future water system that would allow for alternative water sources and solutions.
Councilmember Herb Kai agreed with Councilmember Comerford and recommended continued exploration of alternative water sources.
"Thank you to the staff for a great presentation. We do care, and we are trying to do things to clean up this system as quickly as possible. We need to be held accountable, and we will be accountable," said Mayor Ed Honea.
"We will examine all options including looking at our current resources, our outside financial consultants, and deriving financial alternatives that not only deal with capital cost of construction but also the long-term operations and maintenance," said Town Manager Jamsheed Mehta.
The presentation slides can be downloaded and viewed here. Viewers who were not able to attend the public meeting will be able to watch a recording of the presentation here.
Learn more about Marana Water quality here.
What has been found and where?
The Town has two affected water systems with unregulated compounds above EPA health advisories. The systems are the Picture Rocks (Continental Reserve area) system and the Airline/Lambert (Saguaro Bloom area) system.
The two compounds of interest are: Perfluorinated compounds (PFOA and PFOS), and 1,4-Dioxane. A health advisory is not an enforceable standard within the Safe Drinking Water Act. It is an early stage in a potential regulatory process, and further studies are required on toxicology and national occurrence to determine if a regulatory standard is needed.
Perfluorinated compounds can commonly be found in any successful stain repellant, water repellant, and grease repellant produced in the last 50 years, and are used in the manufacturing of carpets, furniture, paper packaging, leather, coating additives, car waxes and coatings, fire-resistant materials, and fire fighting foams. Exposure is primarily through diet and dust from products. Outside use of the product can directly expose soil, surface water, and eventually groundwater.
In 2016, the United States Environmental Protection Agency lowered the advisory levels for Perfluorinated compounds. Town of Marana Water conducted a test of its water systems, and found the Picture Rocks and Airline/Lambert water systems, and an individual well (Falstaff) to be in excess of the health advisory level for perfluorinated compounds.
1,4-Dioxane is a semi-volatile liquid, used widespread as a stabilizer with chlorinated solvents, paint strippers, greases, waxes, and cosmetics. It migrates rapidly in groundwater. Arizona currently does not have an established guideline for 1,4-Dioxane in drinking water, so the Town of Marana is using the current, most conservative federal EPA guidance of 0.35 ug/L (parts per billion).
Multiple tests concluded that the Picture Rocks and Airline/Lambert water systems, and an individual well (Falstaff water) contained water with levels higher than the advisory level of 0.35 ppb for 1,4-Dioxane.
Recurring tests over the last two years have shown a slight decrease of Perfluorinated compounds and 1,4-Dioxane in the drinking water within the two affected systems. If the current declining trend were to continue, it would still take several years for these compounds to get below the current advisory level. There is no guarantee that the declining trends will continue, or the health advisories will remain the same.
The Town of Marana currently meets regulatory standards as defined by the Safe Drinking Water Act for all of its water systems.
Solutions
· Multiple variables exist, including the United States Environmental Protection Agency's scheduled release this fall of guidance and cleanup criteria for perfluorinated compounds found in soil and groundwater. Determining source is another important factor, whether the compounds are from a primary single source contributor or from the community at large.
· Alternative one: Blending (dilution) would require water sources to be available to dilute the impacted water with water that has non-detectable levels of the target compounds. To meet blending targets, each system would require a replacement capacity of non-detect water at potentially 82%. This devalues the current groundwater well assets to an 18% effectiveness. There is also no guarantee of water quality remaining at non-detect levels at the sites used for blending. The Blending Alternative is high risk.
· COUNCIL DIRECTION- Alternative two: Develop an advanced water treatment approach for each system. Water treatment would require a multi-million dollar capital improvement project for each impacted system to completely remove or destroy the target compounds from the water.
RELATED ARTICLES
October 5, 2018: Arizona Department of Environmental Quality supports Town efforts to address unregulated compounds in drinking water
September 27, 2018: Town Council authorizes creation of water treatment systems for impacted systems
August 15, 2018: Marana Town Council opts for water treatment solution
