Two federal agencies are set to conduct a sweeping set of studies aimed at fully understanding how widespread pollution in the Passaic River has affected the water and the wildlife that rely on it.

The U.S. Fish and Wildlife Service and the National Oceanic and Atmospheric Administration will soon begin studying the Diamond Alkali Superfund site, which includes historic contamination in a roughly 17-mile stretch of the river between Newark Bay and the Dundee Dam in Garfield.

The study is meant to determine how the dumping of hazardous materials into the Passaic River — which is tied to industrial activity in the area dating back to the 1800s — has damaged natural resources like birds, fish and crabs.

The goal of the study and subsequent remediation work is to restore or replace the damaged natural resources, Clay Stern, the USFWS’s case manager for the Diamond Alkali site, said in a statement to NJ Advance Media.

This study is separate from clean-up work that is being overseen by the U.S. Environmental Protection Agency, which is designed to minimize risks to human health.

The EPA expects that cleaning the entire 17-mile stretch of the Passaic to cost $1.4 billion, all of which is supposed to be paid for by the companies responsible for the pollution. The EPA secured a $165 million settlement in 2016 from Occidental Chemical Corporation, just one of the polluters, to fund some of the work on the lower eight miles.

The state has warned people not to eat fish and shellfish from the polluted-stretch of the Passaic River for decades. Previous studies of the river by the EPA and the state of New Jersey have been focused on understand the nature and extent of the pollution. This new work by the USFWS and NOAA will be the first to understand how the pollution has affected birds, fish and their habitats, according to Stern.

The USFWS and NOAA intend to collect data for their study before, during and after the dredging of the site is done for the EPA remediation work. That dredging is expected to begin in 2021, according to the USFWS.

Stern said the study is expected to begin in the spring, and that there is no set timeline for completing the work.

“Each case is unique and the amount of time can vary significantly,” Stern said. “Natural resource damage assessment for sites as complex the Diamond Alkali Superfund Site often take years to complete.”

Read the full natural resource damage assessment Plan for the Diamond Alkali site here.

Read more of NJ.com’s coverage of New Jersey water issues here.

Michael Sol Warren may be reached at mwarren@njadvancemedia.com. Follow him on Twitter @MSolDub. Find NJ.com on Facebook.

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