TALLAHASSEE, Fla. - Conservation groups say Florida's environmental regulators ignored a decade of warning signs - including advice from the U.S. Army Corps of Engineers - and it ultimately led to the Piney Point wastewater leak. Now, they plan to file suit.

The Florida Department of Environmental Protection, HRK Holdings, and the Manatee County Port Authority have all been named in the Notice of Intent to Sue, after April's leak of a phosphogypsum stack, releasing about 215 million gallons of wastewater into Tampa Bay and prompting evacuations.

Jaclyn Lopez, Florida director and senior attorney with the Center for Biological Diversity, said the suit calls for permanent closure of the site and better solutions than dumping the remaining waste into Florida's groundwater.

"If we don't file this lawsuit," said Lopez, "our concern is that the DEP, the county and HRK is going to choose a path of least resistance for getting rid of the waste that they're left managing, and deep-well injection appears to be such a path."

In a statement, the Florida DEP says it's committed to holding all involved accountable, as well as ensuring permanent closure of the site. However, Lopez and other conservation groups say the suit highlights the state's negligence, which allowed the spill to occur.

The groups note DEP is the primary agency for granting permits for operations at the site, and allege that it ignored the advice of federal regulators to not use the site as a place to store dredge material. Lopez said all parties were aware of the risks.

"Piney Point is a well-documented example of the regulatory failures of an industry, but it's not the only one," said Lopez. "We have many other phosphogypsum stacks in Florida that are in various stages of failing or failure."

The groups want to see more effort on cleanup alternatives, such as the phosphate industry-backed use of reverse osmosis systems to clean and filter wastewater.

Other plaintiffs include the ManaSota-88, Our Children's Earth Foundation, Suncoast Waterkeeper and Tampa Bay Waterkeeper.

Residents of East Palestine, Ohio, say they continue to live with health problems, including rashes, nosebleeds and respiratory issues following last year's massive train derailment and chemical spill.

According to the Environmental Protection Agency, 177 tons of solid waste of solid waste and 68 million gallons of water have been transported out of East Palestine for disposal.

Jess Conard, Appalachia director for the advocacy group Beyond Plastics, said vinyl chloride is a key ingredient in making PVC plastic. She argued the disaster highlighted the need to reduce production of industrial plastic and better regulate all stages of the plastic life cycle. She added residents still do not have the resources needed to stay safe.

"We are also in desperate need of residential indoor and outdoor air monitoring and air assessments for our homes," Conard contended. "There are residents within the past month that have reported detections of vinyl chloride outside of their home."

Norfolk Southern recently agreed to a $600 million settlement in an attempt to resolve a string of lawsuits involving thousands of people.

If it gets approval from all parties, it would resolve all class-action claims by people and businesses who were within a 20-mile radius of the derailment site, and personal injury claims within 10 miles. In a statement on the company's website, the company stressed the settlement does not constitute any admission of liability, wrongdoing or fault.

Conard pointed out the settlement will not prevent another train-related environmental disaster from happening. She noted the amount of money in the proposed settlement will hardly leave a dent in the pockets of a company whose profits topped $8 billion last year.

"If the court accepts this settlement, it sets the precedent that there is a corporate price tag for poisoning communities," Conard asserted. "The court must uphold justice for the people."

Congress has stalled on passage of legislation to boost regulations around inspections and fines for railroad companies violating safety standards. Earlier this month, the Biden administration passed a new rule requiring freight operators to have at least two people on board, in an attempt to increase safety.

Chemical plants in West Virginia and other states will be required to curb emissions of toxic, cancer causing pollutants - such as ethylene oxide, chloroprene and other chemicals - under a new Environmental Protection Agency rule.

Hundreds of facilities, most located near low-income or communities of color, will also have to collect air pollution data and submit it to the EPA.

The data will also be made available to communities, which Jeremy Symons - a senior advisor with the Environmental Protection Network - said is an important tool for transparency and environmental justice.

"Not only will this action by EPA reduce these dangerous toxic air pollutants by 96%," said Symons, "but they're also going to require chemical plants to install fenceline air-pollution monitors."

Research has shown that long-term exposure to ethylene oxide and chloroprene can increase the risk of certain types of cancer, such as lymphoma, leukemia, breast cancer and liver cancer.

Children are particularly at risk.

The Biden administration says the rule will slash more than 6,200 tons of toxic air pollution each year in affected regions.

Symons, a former EPA advisor, said the rules come after years of work by local community members and environmental organizations that have sounded the alarm on the impact of deadly air pollution.

"There's been especially high cancer rates in these communities," said Symons. "So it's really significant that EPA has taken action and gone into the communities that have not been protected as much as they should be in the past."

A handful of companies in West Virginia - including Chemours, Koppers and Altivia - will have to comply with the new rules.

Investigative reporting published in 2021 by Mountain State Spotlight and ProPublica have revealed how toxic chemical pollution has harmed the state's majority Black communities.

People working for environmental justice are rallying today at the downtown Pittsburgh headquarters of U.S. Steel, voicing their concerns to company shareholders about creating a healthier future in the Monongahela Valley region.

Japan's Nippon Steel is buying U.S. Steel for more than $14 billion.

Duquesne Mayor Nickole Nesby, an environmental-justice organizer with the group 412Justice, said the asthma rate in the Mon Valley is four to five times higher than the national average. She pointed out they're being left out of important conversations about the sale and are urging better health protections.

"We are actually gathering to demand a seat at the table," she said. "We -- the communities which have been impacted by the pollutants for decades -- have not had a seat at the table. Our voice needs to be heard."

U.S. Steel has had a presence in the Mon Valley since 1901 and currently employs more than 3,000 workers. Nesby said the sale isn't supposed to affect local employment, as U.S. Steel has said it will keep the contract as it currently exists.

U.S. Steel's Mon Valley Works, which includes the Clairton Coke Works, is the biggest coke plant in the country.

NaTisha Washington, communications manager for the Breathe Project, said the plants have a long history of breaking air-quality rules and facing complaints. She added that the plants keep getting fined for exceeding pollution limits - and even have trouble getting new permits.

"There is no transparency with the communities about these air quality days being bad," she said. "No protections, no resources like air filters, or anything that's supporting residents that are affected by these bad-air days."

Washington added that money is being put into a clean-air fund and a Community Benefit Trust. But there has been no visible improvement to community health so far. She noted many Mon Valley residents are feeling the impacts of either poor air or water quality.