Finding PFAS in a community’s water supply can raise urgent questions about health, property, and the cost of cleanup. Holding the responsible companies accountable requires answering another set of questions: Where did the contamination originate? How did people encounter it? What harm resulted? What evidence connects that harm to a particular defendant?
Those answers may involve decades of company records, environmental testing, medical evidence, and scientific analysis. When similar claims arise across the country, attorneys must also coordinate work involving many plaintiffs, defendants, and courts.
At Stag Liuzza, our PFAS litigation attorneys represent individuals, property owners, municipalities, and businesses affected by contamination. This work requires connecting the science behind an exposure with the evidence needed to pursue a legal claim. stagliuzza.com
Understanding that process helps explain why environmental litigation can be complex and why experience with large, coordinated cases matters.
Finding Contamination Is Only the Beginning
A water sample showing PFAS establishes an important fact about the water tested. It does not answer every question necessary to bring a lawsuit.
An investigation may still need to establish:
- Which chemicals are present.
- Where they originated.
- When releases occurred.
- How contamination reached a water supply or property.
- Which people or entities suffered harm.
- What role each potential defendant played.
Consider a community near an airport and several industrial facilities. Finding PFAS in nearby groundwater does not, by itself, establish which location contributed to the contamination or which products were involved.
The investigation must build a supported explanation of what happened. That can require environmental records, historical documents, site investigations, and expert analysis.
1. Tracing PFAS to Its Source Requires Scientific Investigation
Contamination does not necessarily remain where a chemical was first released.
EPA research explains that PFAS can move from contaminated soil into groundwater and that predicting those effects requires attention to site-specific conditions. Its groundwater guidance also recognizes that several PFAS source areas may exist at the same site. US EPA
For litigation, these conditions create practical questions. Did contamination migrate from a neighboring property? Were there multiple release locations? Does the available testing support the suspected pathway?
Environmental specialists may examine groundwater movement, soil conditions, sampling results, and the history of activities at a facility. Attorneys then evaluate how those findings relate to the conduct of potentially responsible parties.
This is one reason water contamination litigation requires more than identifying a polluted well or water supply. A case needs evidence connecting the contamination to its alleged source.
2. Reconstructing Exposure Can Mean Looking Back Decades
People often learn about contamination long after the suspected exposure began.
Someone may have lived in several communities, worked at multiple facilities, or used different drinking water sources. A firefighter’s work history may span departments, training locations, and changes in the products used.
Reconstructing that history can involve:
- Residential addresses and dates.
- Water service records.
- Employment and military records.
- Historical water testing.
- Product purchasing records.
- Firefighting and training records.
- Earlier environmental investigations.
Missing records can make the work more difficult. Current testing also may not establish what conditions were like years earlier.
For example, a recent sample from a treated water supply may tell investigators little about the untreated water residents drank before treatment began. Historical conditions need to be evaluated using the evidence available for the relevant period.
Attorneys and experts must identify both what the records support and where uncertainty remains.
3. Proving Harm Requires More Than Proving Exposure
A central challenge in environmental litigation is connecting the alleged exposure to the particular harm claimed.
For an individual injury case, attorneys may need to evaluate a diagnosis, exposure history, medical literature, and other potential explanations for the illness. For a municipality, the investigation may focus on testing expenses, treatment needs, and contamination-related financial losses.
These inquiries require different evidence.
| Question | Evidence that may help answer it |
| Where did contamination originate? | Site records, product information, environmental testing, and source analysis |
| How did exposure occur? | Water records, work history, residential history, and environmental pathways |
| What injury or loss occurred? | Medical records, property records, treatment plans, and financial documentation |
| How are the exposure and harm connected? | Relevant scientific research and qualified expert analysis |
| What compensation is supported? | Bills, cost estimates, employment records, and evidence of future needs |
A PFAS blood test has a limited role in this process. The Agency for Toxic Substances and Disease Registry explains that testing can measure certain PFAS in blood but does not identify a current or future health problem or predict future health outcomes. www.atsdr.cdc.gov
The legal investigation must consider the broader evidence. Neither a positive environmental sample nor a blood test independently resolves the questions of causation and liability.
4. Multiple Companies May Have Different Roles
A contamination case may involve companies that manufactured chemicals, formulated products, distributed them, or used them at a particular location.
Identifying a company’s role requires examining what it actually did. Investigators may review purchasing records, product formulations, facility operations, disposal practices, and communications about potential risks.
Each defendant may raise different factual or legal defenses. A manufacturer may dispute that its product was used at the location. A facility operator may dispute that contamination migrated from its property. Parties may disagree about the significance of the testing or the cause of the claimed harm.
The presence of several companies does not establish that all are liable. The case must address the evidence concerning each party.
That detailed work is central to environmental pollution claims, where responsibility may be contested across a long history of products, operations, and releases.
What Is an Environmental MDL?
Some environmental disputes involve lawsuits filed in different federal courts that share important factual questions. Those cases may be brought together through multidistrict litigation, commonly called an MDL.
The Judicial Panel on Multidistrict Litigation determines whether cases should be transferred to one federal district for coordinated or consolidated pretrial proceedings. It also selects the court and judge responsible for that work. United States
Coordination allows shared issues to be addressed together. For example, multiple cases may depend on the same company documents, witness testimony, or scientific evidence.
An MDL does not automatically make every plaintiff’s claim identical. Individuals may have different exposure histories and diagnoses. Water systems may have different contamination levels, infrastructure, and costs.
Not every environmental lawsuit becomes part of an MDL. The process applies when the requirements for federal coordination are met.
The AFFF Litigation Shows How Different Claims Can Share Common Questions
The federal AFFF MDL is pending in the District of South Carolina. It involves allegations that PFAS-containing firefighting foam contaminated groundwater near military bases, airports, and other locations where the products were used.
The court describes claims involving personal injury, medical monitoring, property damage, and other economic losses. MDL
These claims may share questions about products and alleged contamination while requiring different evidence about each plaintiff’s harm.
Someone pursuing a firefighting foam lawsuit may need a detailed occupational and medical history. A water system may need records concerning affected water sources and treatment requirements.
Coordinating shared work can improve efficiency, but attorneys still must develop the facts relevant to their own clients.
5. Coordinating Large Litigation Requires Organization and Resources
Large environmental litigation can generate substantial amounts of material: company documents, testing data, expert reports, testimony, and records from individual claimants.
The challenge is not simply collecting it. Attorneys must identify what matters, evaluate its reliability, and organize it around the issues the court needs to decide.
Shared work may include:
- Reviewing documents produced by defendants.
- Questioning company witnesses.
- Developing expert evidence.
- Addressing disputes over access to records.
- Briefing common legal issues.
- Organizing case-specific information.
Leadership structures help coordinate this work across participating law firms.
Stag Liuzza has a documented role in that process. In 2024, the firm announced that Michael Stag was reappointed to the Plaintiffs’ Executive Committee in the AFFF MDL. Its August 2026 Trenton announcement also identifies his service on that committee. Stag Liuzza
That involvement provides a concrete example of the firm’s experience within national PFAS litigation, beyond representing clients in individual cases.
Why Can Environmental MDLs Take So Long?
These cases often require several stages of work before the parties can meaningfully evaluate liability and damages.
Attorneys may need to reconstruct historical events, obtain documents, question witnesses, develop scientific evidence, and address challenges to that evidence. The court may also need to resolve issues that affect many cases.
The Federal Judicial Center’s MDL guidance describes responsibilities that include coordinating cases, identifying differences in applicable law, and organizing discovery and motions. Some cases may resolve through settlement or rulings; unresolved transferred cases may be returned to their original courts when appropriate. jpml.uscourts.gov
There is no single timeline that applies to every claim. Progress in one category of cases does not necessarily determine the timing or outcome of another.
For clients, clear communication matters throughout this process. They should understand what stage their claim has reached, what information is needed, and which questions remain unresolved.
What Stag Liuzza’s Trenton Recovery Illustrates
Complex litigation ultimately needs to address a client’s concrete losses and goals.
Stag Liuzza’s announced recovery of approximately $11.3 million for Trenton Water Works provides an example involving public infrastructure. The firm reported that the settlement funds would support improvements to treatment systems, laboratory capabilities, and infrastructure reliability. stagliuzza.com
The Trenton Water Works recovery shows how national litigation can have a practical local purpose: helping a water system fund work needed to address contamination.
Other clients may have different goals, such as compensation for a serious illness or losses involving contaminated property. Each requires evidence tailored to that claim. A prior recovery does not determine the result of another case.
You Do Not Need to Solve the Entire Case Before Seeking Help
People affected by suspected contamination often have only part of the picture. You may have a water notice, a diagnosis, an employment history, or concerns about a nearby facility.
Start by keeping the information available to you:
- Testing results and contamination notices.
- Addresses and dates of residence.
- Relevant employment or service history.
- Medical records.
- Property records.
- Documented expenses and communications.
You do not need to identify every defendant or obtain your own expert opinion before contacting an attorney. A legal review can help determine which questions need further investigation and whether deadlines require attention.
Working With Stag Liuzza on a PFAS or Environmental Claim
PFAS claims require attorneys to connect scientific findings, historical evidence, legal responsibility, and a client’s individual circumstances. Large MDLs add the demands of coordinating shared work while preserving the facts that make each claim different.
Stag Liuzza represents individuals, property owners, municipalities, and businesses affected by PFAS contamination. Our PFAS lawyers can review your circumstances and explain what an investigation may involve. stagliuzza.com
Contact Stag Liuzza to discuss suspected exposure, contaminated property, or your community’s water contamination concerns.
