WASHINGTON (AP) — The Environmental Protection Agency announced a series of enforcement actions Wednesday to address air pollution, unsafe drinking water and other problems afflicting minority communities in three Gulf Coast states, following a “Journey to Justice” tour by Administrator Michael Regan last fall.

The agency will conduct unannounced inspections of chemical plants, refineries and other industrial sites suspected of polluting air and water and causing health problems to nearby residents, Regan said. And it will install air monitoring equipment in Louisiana's “chemical corridor” to enhance enforcement at chemical and plastics plants between New Orleans and Baton Rouge. The region contains several hotspots where cancer risks are far above national levels.

The EPA also issued a notice to the city of Jackson, Mississippi, saying its aging and overwhelmed drinking water system violates the federal Safe Drinking Water Act. The order directs the city to outline a plan to “correct the significant deficiencies identified” in an EPA report within 45 days.

In separate letters, Regan urged city and state officials to use nearly $79 million in funding allocated to Mississippi under the bipartisan infrastructure law "to solve some of the most dire water needs in Jackson and other areas of need across Mississippi.''

The actions were among more than a dozen steps announced being taken in response to Regan's tour last November. Regan visited low-income, mostly minority communities in Mississippi, Louisiana and Texas as part of an effort to focus federal attention on communities adversely affected by decades of industrial pollution.

A Toxics Release Inventory prepared by the EPA shows that African Americans and other minority groups make up 56% of those living near toxic sites such as refineries, landfills and chemical plants. Negative effects include chronic health problems such as asthma, diabetes and hypertension.

“In every community I visited during the Journey to Justice tour, the message was clear: residents have suffered far too long and local, state and federal agencies have to do better,” Regan said.

The unannounced inspections of chemical plants and other sites “are going to keep these facilities on their toes,'' he told reporters on a conference call.

Inspections currently are done on a schedule or with advance notice, Regan said, but that is about to change. “We are amping up our aggressiveness to utilize a tool that's in our toolbox that ... has been there for quite some time,'' he said.

When facilities are found to be noncompliant, the EPA "will use all available tools to hold them accountable,'' he added.

A pilot project combining high-tech air pollution monitoring with additional inspectors will begin in three Louisiana parishes: St. John the Baptist, St. James and Calcasieu. The parishes are home to scores of industrial sites and are long plagued by water and air pollution.

President Joe Biden has made addressing racial disparities, including those related to the environment, central to his agenda. He has pledged that at least 40% of new spending on climate and the environment go to poor and minority communities. The administration's commitment to the issue has come under renewed scrutiny in recent weeks, as two key environmental justice appointees departed. Cecilia Martinez, a top official at the White House Council on Environmental Quality, and David Kieve, who conducted outreach with environmental justice groups, both left the White House, putting a spotlight on promises yet to be fulfilled.

Regan, a former environmental regulator in North Carolina, has made environmental justice a top priority since taking over as EPA head last year. As the first Black man to lead the agency, the issue “is really personal for me, as well as professional,″ he told The Associated Press in November.

"I pledge to do better by people in communities who have been hurting for far too long,” he said Tuesday.

Historically marginalized communities like St. John and St. James, along with cities such as New Orleans, Jackson and Houston, will benefit from the $1 trillion bipartisan infrastructure law signed by Biden, Regan said. The law includes $55 billion for water and wastewater infrastructure, while a sweeping climate and social policy bill pending in the Senate would pump more than twice that amount into EPA programs to clean up the environment and address water and environmental justice issues.

As part of its enforcement action, the EPA is requiring a former DuPont petrochemical plant in La Place, Louisiana, to install fence-line monitors to identify emissions from the site, Regan said. The plant is now owned by the Japanese conglomerate Denka.

The agency also said it will push for greater scrutiny of a proposed expansion of a Formosa Plastics plant in St. James and issued a notice of violation to a Nucor Steel plant that emits hydrogen sulfide and other harmful chemicals.

Regan said he has spoken with New Orleans Mayor LaToya Cantrell about Gordon Plaza, a city neighborhood built on the site of a former toxic landfill. Gordon Plaza was designated as a Superfund site in the 1990s, but dozens of mostly Black families still live there.

The EPA will review the site, starting in March, Regan said, and will add nine homes not included in earlier plans to help families move. City officials hope to use money from the infrastructure law to relocate families and build a solar farm on the site.