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Agriculture
7 min read
Areas of Expertise :
Hydrology, Environmental Engineering, Damages
Published Date:
Last Modified Date:
Jurisdiction:
Federal. Ninth Circuit
Court:
Perchlorate detected in Pomona's municipal water supply led to a long-running dispute over where the contaminant came from and who should bear the cost of treating affected groundwater. Pomona obtains part of its drinking water from wells drawing from the Chino Basin. After California established a maximum contaminant level of six parts per billion for perchlorate in 2007, the city shut down affected wells, purchased replacement water, blended water supplies, modified treatment operations, and planned for longer-term perchlorate removal. Pomona later alleged that sodium nitrate fertilizer imported from Chile's Atacama Desert decades earlier contained perchlorate that moved from agricultural land into groundwater serving the city.
Pomona filed suit on October 15, 2010, naming SQM North America Corporation and its parent company, SQM, as defendants. Pomona later withdrew its claim against SQM. The litigation examined historical fertilizer use, groundwater movement, stable isotope analysis, competing contamination sources, drinking-water treatment, product design, and abatement costs. After three jury trials and several appeals to the U.S. Court of Appeals for the Ninth Circuit, a jury found SQMNA liable in 2021 and awarded Pomona $48,128,378. The damages award was later reduced to $30,280,802, which SQMNA paid before SQM reported that the case was terminated.
The City of Pomona filed suit after investigating perchlorate found in groundwater used by its public water system. California had adopted a maximum contaminant level of six parts per billion for perchlorate in drinking water in 2007. Pomona responded to affected supplies by shutting down wells, obtaining replacement water, blending water sources, and modifying treatment operations. The city alleged that perchlorate contained in Chilean sodium nitrate fertilizer had entered the Chino Basin groundwater system. The action was later removed from California state court to the U.S. District Court for the Central District of California.
Before the first jury trial, the district court excluded testimony from Pomona expert witness Dr. Neil Sturchio. He had used stable chlorine and oxygen isotope analysis to investigate the source of perchlorate detected in groundwater samples. His work involved extracting and purifying perchlorate, measuring its isotope composition, and comparing the results with reference samples from known sources. The Ninth Circuit reversed the exclusion, finding that several objections concerned the strength of the evidence rather than whether the methodology could be presented to a jury. The case returned to the district court for trial.
SQMNA petitioned the U.S. Supreme Court to review the Ninth Circuit decision concerning Sturchio's testimony. The Supreme Court denied certiorari on December 15, 2014. The Ninth Circuit ruling therefore remained in place. Sturchio's isotope evidence could be presented when the groundwater contamination case proceeded to trial.
The first trial examined whether SQMNA's sodium nitrate fertilizer was connected to the perchlorate found in Pomona's groundwater. Sturchio addressed the isotope characteristics of the contamination, while Pomona hydrology expert witness Dr. Stephen Wheatcraft discussed the proposed movement of perchlorate from historically fertilized land into the city's water system. SQMNA challenged Pomona's source-attribution and groundwater-causation theories. After seven days of testimony and argument, the jury found that SQMNA's fertilizer was not a substantial factor in causing Pomona's harm. Pomona appealed.
The Ninth Circuit vacated the first judgment after reviewing the treatment of scientific evidence from both sides. During the years between Sturchio's original report and the trial, additional research had expanded the perchlorate isotope database and added new analytical work. The appellate court concluded that Pomona should have been permitted to present those later scientific developments. It also found that the district court had not made sufficient reliability findings before allowing testimony from SQMNA expert witness Dr. Richard Laton, who proposed numerous other possible sources of perchlorate. The case was returned for another trial.
The second trial addressed Pomona's strict products liability claim under California's risk-benefit test for product design. The jury again returned a verdict for SQMNA. Pomona challenged the instructions that told jurors how to assess the risks and benefits associated with the fertilizer. The dispute then returned to the Ninth Circuit for review of the design-defect instructions used at trial.
The Ninth Circuit concluded that the second jury had been incorrectly instructed to consider the fertilizer's risks and benefits according to knowledge available when the product was historically used. The majority held that California's risk-benefit test allowed the jury to consider knowledge obtained after the product had been manufactured and sold. The judgment was reversed, and the court ordered a complete third trial. Judge Kenneth Lee dissented from the majority's interpretation of California law.
The third trial produced a different result. The jury found SQMNA liable on Pomona's California strict products liability claim and awarded the city $48,128,378. Sturchio testified that approximately 88 percent of the perchlorate in Pomona's groundwater was derived from SQMNA's Chilean sodium nitrate fertilizer. The evidence also addressed historical perchlorate concentrations in the fertilizer, movement of contamination into groundwater, drinking-water treatment, and future abatement costs. The district court entered judgment for Pomona on January 27, 2022.
SQMNA appealed the third verdict, challenging the evidence of design defect, the statute of limitations, foreseeability, and the amount of damages. The Ninth Circuit did not disturb the jury's liability finding but concluded that the district court's stated reasons for upholding the full $48.1 million award were not adequately supported by the record. Pomona's damages expert Peter von Bucher estimated $30,280,802 in perchlorate-abatement costs, while SQMNA expert Dr. Robert Trussell testified about the cost of operating Pomona's existing anion-exchange plants in perchlorate mode. The appellate court found that the treatment figure relied on by the district court included costs for both nitrate and perchlorate, even though SQMNA's liability concerned perchlorate. The damages issue was returned to the district court for further proceedings.
Following the appellate ruling, the district court reduced the award from $48,128,378 to $30,280,802. That amount corresponded with Pomona's evidence concerning perchlorate-abatement costs. SQMNA paid the reduced judgment. SQM later reported that the payment had been made and that the Pomona litigation was terminated.
United States Court of Appeals for the Ninth Circuit
Case Name:
City of Pomona v. SQM North America Corporation
Pomona alleged that perchlorate from Chilean sodium nitrate fertilizer contaminated groundwater used for its municipal drinking-water supply.
The litigation focused on isotope-based source identification, groundwater migration, competing contamination sources, and treatment costs.
The Ninth Circuit overturned the first two defense verdicts due to errors involving expert evidence and jury instructions.
In 2021, a third jury found SQM North America liable and awarded Pomona approximately $48.1 million in damages.
The award was reduced to $30.28 million in 2023 to reflect perchlorate-abatement costs. SQMNA paid the judgment, ending the litigation.
Groundwater
Groundwater Contamination
Geochemistry
Environmental Contamination
Environmental Remediation
Water Analysis
Water Quality
Water Resources
Water Treatment
Water and Wastewater Engineering
Perchlorate detected in Pomona's municipal water supply led to a long-running dispute over where the contaminant came from and who should bear the cost of treating affected groundwater. Pomona obtains part of its drinking water from wells drawing from the Chino Basin. After California established a maximum contaminant level of six parts per billion for perchlorate in 2007, the city shut down affected wells, purchased replacement water, blended water supplies, modified treatment operations, and planned for longer-term perchlorate removal. Pomona later alleged that sodium nitrate fertilizer imported from Chile's Atacama Desert decades earlier contained perchlorate that moved from agricultural land into groundwater serving the city.
Pomona filed suit on October 15, 2010, naming SQM North America Corporation and its parent company, SQM, as defendants. Pomona later withdrew its claim against SQM. The litigation examined historical fertilizer use, groundwater movement, stable isotope analysis, competing contamination sources, drinking-water treatment, product design, and abatement costs. After three jury trials and several appeals to the U.S. Court of Appeals for the Ninth Circuit, a jury found SQMNA liable in 2021 and awarded Pomona $48,128,378. The damages award was later reduced to $30,280,802, which SQMNA paid before SQM reported that the case was terminated.
The City of Pomona filed suit after investigating perchlorate found in groundwater used by its public water system. California had adopted a maximum contaminant level of six parts per billion for perchlorate in drinking water in 2007. Pomona responded to affected supplies by shutting down wells, obtaining replacement water, blending water sources, and modifying treatment operations. The city alleged that perchlorate contained in Chilean sodium nitrate fertilizer had entered the Chino Basin groundwater system. The action was later removed from California state court to the U.S. District Court for the Central District of California.
Before the first jury trial, the district court excluded testimony from Pomona expert witness Dr. Neil Sturchio. He had used stable chlorine and oxygen isotope analysis to investigate the source of perchlorate detected in groundwater samples. His work involved extracting and purifying perchlorate, measuring its isotope composition, and comparing the results with reference samples from known sources. The Ninth Circuit reversed the exclusion, finding that several objections concerned the strength of the evidence rather than whether the methodology could be presented to a jury. The case returned to the district court for trial.
SQMNA petitioned the U.S. Supreme Court to review the Ninth Circuit decision concerning Sturchio's testimony. The Supreme Court denied certiorari on December 15, 2014. The Ninth Circuit ruling therefore remained in place. Sturchio's isotope evidence could be presented when the groundwater contamination case proceeded to trial.
The first trial examined whether SQMNA's sodium nitrate fertilizer was connected to the perchlorate found in Pomona's groundwater. Sturchio addressed the isotope characteristics of the contamination, while Pomona hydrology expert witness Dr. Stephen Wheatcraft discussed the proposed movement of perchlorate from historically fertilized land into the city's water system. SQMNA challenged Pomona's source-attribution and groundwater-causation theories. After seven days of testimony and argument, the jury found that SQMNA's fertilizer was not a substantial factor in causing Pomona's harm. Pomona appealed.
The Ninth Circuit vacated the first judgment after reviewing the treatment of scientific evidence from both sides. During the years between Sturchio's original report and the trial, additional research had expanded the perchlorate isotope database and added new analytical work. The appellate court concluded that Pomona should have been permitted to present those later scientific developments. It also found that the district court had not made sufficient reliability findings before allowing testimony from SQMNA expert witness Dr. Richard Laton, who proposed numerous other possible sources of perchlorate. The case was returned for another trial.
The second trial addressed Pomona's strict products liability claim under California's risk-benefit test for product design. The jury again returned a verdict for SQMNA. Pomona challenged the instructions that told jurors how to assess the risks and benefits associated with the fertilizer. The dispute then returned to the Ninth Circuit for review of the design-defect instructions used at trial.
The Ninth Circuit concluded that the second jury had been incorrectly instructed to consider the fertilizer's risks and benefits according to knowledge available when the product was historically used. The majority held that California's risk-benefit test allowed the jury to consider knowledge obtained after the product had been manufactured and sold. The judgment was reversed, and the court ordered a complete third trial. Judge Kenneth Lee dissented from the majority's interpretation of California law.
The third trial produced a different result. The jury found SQMNA liable on Pomona's California strict products liability claim and awarded the city $48,128,378. Sturchio testified that approximately 88 percent of the perchlorate in Pomona's groundwater was derived from SQMNA's Chilean sodium nitrate fertilizer. The evidence also addressed historical perchlorate concentrations in the fertilizer, movement of contamination into groundwater, drinking-water treatment, and future abatement costs. The district court entered judgment for Pomona on January 27, 2022.
SQMNA appealed the third verdict, challenging the evidence of design defect, the statute of limitations, foreseeability, and the amount of damages. The Ninth Circuit did not disturb the jury's liability finding but concluded that the district court's stated reasons for upholding the full $48.1 million award were not adequately supported by the record. Pomona's damages expert Peter von Bucher estimated $30,280,802 in perchlorate-abatement costs, while SQMNA expert Dr. Robert Trussell testified about the cost of operating Pomona's existing anion-exchange plants in perchlorate mode. The appellate court found that the treatment figure relied on by the district court included costs for both nitrate and perchlorate, even though SQMNA's liability concerned perchlorate. The damages issue was returned to the district court for further proceedings.
Following the appellate ruling, the district court reduced the award from $48,128,378 to $30,280,802. That amount corresponded with Pomona's evidence concerning perchlorate-abatement costs. SQMNA paid the reduced judgment. SQM later reported that the payment had been made and that the Pomona litigation was terminated.
Isotope Geochemistry Expert Witness (Plaintiff)
Dr. Neil Sturchio used stable isotope analysis to examine chlorine and oxygen isotope ratios in perchlorate from Pomona's groundwater. He compared those measurements with data from known perchlorate sources and concluded that most of the perchlorate had an Atacama Desert origin.
Hydrology Expert Witness (Plaintiff)
Dr. Stephen Wheatcraft testified about how perchlorate allegedly moved from historically fertilized orchard areas into Pomona's water system. His testimony addressed the groundwater pathway that formed part of the city's causation theory.
Geochemistry Expert Witness (Defense)
Dr. Ramon Aravena challenged aspects of Sturchio's isotope analysis, including questions about reproducibility and the completeness of the reference database used to compare perchlorate sources.
Alternative-Source Expert Witness (Defense)
Dr. Richard Laton testified that perchlorate in Pomona's water system could have originated from numerous sources other than Chilean sodium nitrate fertilizer. He also questioned whether Pomona's environmental investigation had adequately evaluated other possible sources.
Water Treatment Cost Expert Witness (Defense)
Dr. Robert Trussell testified about the costs associated with operating Pomona's existing anion-exchange treatment plants in perchlorate mode. His testimony later became part of the dispute over the amount of recoverable treatment costs.
Damages Expert Witness (Plaintiff)
Peter von Bucher calculated approximately $30,280,802 in perchlorate-abatement costs. That figure became part of the 2023 appellate review of the jury's original $48.1 million damages award.
Environmental Engineering Expert Witness (Inferred)
An environmental engineering expert could address groundwater contamination, contaminant migration, drinking-water treatment, remediation methods, and the design or operation of treatment systems used to reduce perchlorate concentrations. In a dispute involving Pomona's water system, this type of expert could also evaluate treatment alternatives, system performance, and costs associated with long-term groundwater remediation.
Isotope Testing Was Used to Trace Perchlorate Sources
Pomona relied on stable isotope analysis to investigate where the perchlorate in its groundwater originated. Sturchio examined chlorine and oxygen isotope ratios and compared those measurements with samples from known perchlorate sources. His analysis associated most of the detected perchlorate with material from the Atacama Desert. The litigation then examined whether the isotope evidence, historical fertilizer records, and groundwater data connected that contamination to SQMNA's product.
Source Identification and Groundwater Causation Were Separate
Finding an isotope pattern associated with the Atacama Desert did not resolve every part of the causation dispute. Pomona also presented evidence connecting the fertilizer with its historical use in the area and explaining how perchlorate could move from agricultural land into groundwater supplying municipal wells. SQMNA challenged both the connection to its product and the proposed groundwater pathway. These questions remained disputed through multiple trials.
Scientific Research Changed During the Litigation
Sturchio's original work was prepared years before the first full trial. During the period when the case moved through appellate review, additional isotope research became available and the reference database expanded. Pomona sought to present those later developments when the case returned to the district court. In 2017, the Ninth Circuit concluded that restricting Sturchio to the scientific record reflected in his earlier report had improperly limited Pomona's presentation of its source-attribution evidence.
Treatment Costs Had to Be Tied to Perchlorate
The difference between nitrate treatment and perchlorate treatment became part of the damages dispute. Pomona's damages evidence placed perchlorate-abatement costs at approximately $30.28 million, while other evidence described higher operating costs that included treatment for both nitrate and perchlorate. The Ninth Circuit concluded that the district court's stated reasons did not adequately support the full $48.1 million award. The judgment was later reduced to the amount reflected in Pomona's perchlorate-abatement calculation.
Historical Fertilizer Use Led to a Modern Water Claim
The fertilizer at issue had been distributed and used decades before Pomona filed suit in 2010. The parties therefore relied on a combination of historical product records, agricultural-use evidence, groundwater testing, isotope measurements, drinking-water standards, and treatment-cost calculations. The long period between the historical fertilizer use and the lawsuit also produced a statute-of-limitations dispute over when Pomona suffered legally actionable harm. The jury's finding on timeliness remained in place after the final appeal.
The litigation ended after three jury trials and repeated appellate review. Pomona lost the first two trials, but both judgments were set aside after the Ninth Circuit identified errors involving expert evidence and jury instructions. The third jury found SQMNA liable in September 2021 and awarded $48,128,378. The Ninth Circuit left the liability finding in place in 2023 but returned the damages issue to the district court, where the award was reduced to $30,280,802. SQMNA paid the reduced judgment, and SQM later reported that the case was terminated.
United States Court of Appeals for the Ninth Circuit
The case involved perchlorate, a contaminant detected in groundwater used by Pomona's municipal water system. California established a maximum contaminant level of six parts per billion for perchlorate in drinking water in 2007. Pomona alleged that much of the contamination came from sodium nitrate fertilizer imported from Chile's Atacama Desert and historically applied to agricultural land.
When did Pomona file its lawsuit against SQM North America?
Pomona filed the lawsuit on October 15, 2010, in California Superior Court for Los Angeles County. The action was later removed to the U.S. District Court for the Central District of California. The case continued through three jury trials and several appellate proceedings before reaching its final monetary disposition in 2023.
Why were three jury trials held in the case?
SQMNA prevailed at the first trial in 2015, but the Ninth Circuit vacated that judgment after finding errors involving the treatment of scientific evidence. SQMNA also prevailed at the second trial in 2018, but the Ninth Circuit later found an error in the jury instructions governing California's risk-benefit design-defect test. A third trial was held in 2021, when the jury found SQMNA liable.
What did the Ninth Circuit decide about the 2021 verdict?
In 2023, the Ninth Circuit left the jury's liability finding against SQMNA in place. The court rejected arguments seeking to overturn the verdict based on the evidence of design defect, timeliness, foreseeability, and related issues. It returned the damages issue to the district court because the reasons the district court had given for upholding the full $48.1 million award were not adequately supported by the record.
What steps did Pomona take after detecting perchlorate?
Isotope Geochemistry Expert Witness (Plaintiff)
Dr. Neil Sturchio used stable isotope analysis to examine chlorine and oxygen isotope ratios in perchlorate from Pomona's groundwater. He compared those measurements with data from known perchlorate sources and concluded that most of the perchlorate had an Atacama Desert origin.
Hydrology Expert Witness (Plaintiff)
Dr. Stephen Wheatcraft testified about how perchlorate allegedly moved from historically fertilized orchard areas into Pomona's water system. His testimony addressed the groundwater pathway that formed part of the city's causation theory.
Geochemistry Expert Witness (Defense)
Dr. Ramon Aravena challenged aspects of Sturchio's isotope analysis, including questions about reproducibility and the completeness of the reference database used to compare perchlorate sources.
Alternative-Source Expert Witness (Defense)
Dr. Richard Laton testified that perchlorate in Pomona's water system could have originated from numerous sources other than Chilean sodium nitrate fertilizer. He also questioned whether Pomona's environmental investigation had adequately evaluated other possible sources.
Water Treatment Cost Expert Witness (Defense)
Dr. Robert Trussell testified about the costs associated with operating Pomona's existing anion-exchange treatment plants in perchlorate mode. His testimony later became part of the dispute over the amount of recoverable treatment costs.
Damages Expert Witness (Plaintiff)
Peter von Bucher calculated approximately $30,280,802 in perchlorate-abatement costs. That figure became part of the 2023 appellate review of the jury's original $48.1 million damages award.
Environmental Engineering Expert Witness (Inferred)
An environmental engineering expert could address groundwater contamination, contaminant migration, drinking-water treatment, remediation methods, and the design or operation of treatment systems used to reduce perchlorate concentrations. In a dispute involving Pomona's water system, this type of expert could also evaluate treatment alternatives, system performance, and costs associated with long-term groundwater remediation.
Isotope Testing Was Used to Trace Perchlorate Sources
Pomona relied on stable isotope analysis to investigate where the perchlorate in its groundwater originated. Sturchio examined chlorine and oxygen isotope ratios and compared those measurements with samples from known perchlorate sources. His analysis associated most of the detected perchlorate with material from the Atacama Desert. The litigation then examined whether the isotope evidence, historical fertilizer records, and groundwater data connected that contamination to SQMNA's product.
Source Identification and Groundwater Causation Were Separate
Finding an isotope pattern associated with the Atacama Desert did not resolve every part of the causation dispute. Pomona also presented evidence connecting the fertilizer with its historical use in the area and explaining how perchlorate could move from agricultural land into groundwater supplying municipal wells. SQMNA challenged both the connection to its product and the proposed groundwater pathway. These questions remained disputed through multiple trials.
Scientific Research Changed During the Litigation
Sturchio's original work was prepared years before the first full trial. During the period when the case moved through appellate review, additional isotope research became available and the reference database expanded. Pomona sought to present those later developments when the case returned to the district court. In 2017, the Ninth Circuit concluded that restricting Sturchio to the scientific record reflected in his earlier report had improperly limited Pomona's presentation of its source-attribution evidence.
Treatment Costs Had to Be Tied to Perchlorate
The difference between nitrate treatment and perchlorate treatment became part of the damages dispute. Pomona's damages evidence placed perchlorate-abatement costs at approximately $30.28 million, while other evidence described higher operating costs that included treatment for both nitrate and perchlorate. The Ninth Circuit concluded that the district court's stated reasons did not adequately support the full $48.1 million award. The judgment was later reduced to the amount reflected in Pomona's perchlorate-abatement calculation.
Historical Fertilizer Use Led to a Modern Water Claim
The fertilizer at issue had been distributed and used decades before Pomona filed suit in 2010. The parties therefore relied on a combination of historical product records, agricultural-use evidence, groundwater testing, isotope measurements, drinking-water standards, and treatment-cost calculations. The long period between the historical fertilizer use and the lawsuit also produced a statute-of-limitations dispute over when Pomona suffered legally actionable harm. The jury's finding on timeliness remained in place after the final appeal.
The litigation ended after three jury trials and repeated appellate review. Pomona lost the first two trials, but both judgments were set aside after the Ninth Circuit identified errors involving expert evidence and jury instructions. The third jury found SQMNA liable in September 2021 and awarded $48,128,378. The Ninth Circuit left the liability finding in place in 2023 but returned the damages issue to the district court, where the award was reduced to $30,280,802. SQMNA paid the reduced judgment, and SQM later reported that the case was terminated.
United States Court of Appeals for the Ninth Circuit
The case involved perchlorate, a contaminant detected in groundwater used by Pomona's municipal water system. California established a maximum contaminant level of six parts per billion for perchlorate in drinking water in 2007. Pomona alleged that much of the contamination came from sodium nitrate fertilizer imported from Chile's Atacama Desert and historically applied to agricultural land.
When did Pomona file its lawsuit against SQM North America?
Pomona filed the lawsuit on October 15, 2010, in California Superior Court for Los Angeles County. The action was later removed to the U.S. District Court for the Central District of California. The case continued through three jury trials and several appellate proceedings before reaching its final monetary disposition in 2023.
Why were three jury trials held in the case?
SQMNA prevailed at the first trial in 2015, but the Ninth Circuit vacated that judgment after finding errors involving the treatment of scientific evidence. SQMNA also prevailed at the second trial in 2018, but the Ninth Circuit later found an error in the jury instructions governing California's risk-benefit design-defect test. A third trial was held in 2021, when the jury found SQMNA liable.
What did the Ninth Circuit decide about the 2021 verdict?
In 2023, the Ninth Circuit left the jury's liability finding against SQMNA in place. The court rejected arguments seeking to overturn the verdict based on the evidence of design defect, timeliness, foreseeability, and related issues. It returned the damages issue to the district court because the reasons the district court had given for upholding the full $48.1 million award were not adequately supported by the record.
What steps did Pomona take after detecting perchlorate?
After California adopted a six-parts-per-billion limit for perchlorate in drinking water, Pomona took several steps to manage affected supplies. The city shut down certain wells, purchased replacement water, blended groundwater with other sources, and adjusted treatment operations. It also evaluated longer-term treatment options for reducing perchlorate concentrations in its municipal water system.
Groundwater
Groundwater Contamination
Geochemistry
Environmental Contamination
Environmental Remediation
Water Analysis
Water Quality
Water Resources
Water Treatment
Water and Wastewater Engineering
Agriculture, +4
Agriculture
Environmental Engineering, +4
Agriculture
After California adopted a six-parts-per-billion limit for perchlorate in drinking water, Pomona took several steps to manage affected supplies. The city shut down certain wells, purchased replacement water, blended groundwater with other sources, and adjusted treatment operations. It also evaluated longer-term treatment options for reducing perchlorate concentrations in its municipal water system.