FAST-41 Initiation Notice

Mosaic Fertilizer, LLC
Riverview East Stack Extension (ESE)

Project Information
Title: Riverview East Stack Extension (ESE)
Sector: Manufacturing
Project Location:
Riverview Fertilizer Manufacturing Plant:
Country: United States
Street Address: 8813 US Hwy 41 S
City: Riverview State: Florida Zip: 33578
County: Hillsborough
Project Coordinates:
Latitude: 27.862641 North
Longitude: -81.39013 West
Project Sponsor Contact Information Company Name/Agency: Mosaic Fertilizer, LLC Project Sponsor: Russell Schweiss
Street Address: 13830 Circa Crossing Drive
City: Lithia State: Florida Zip: 33547
POC Name: Russell Schweiss
POC Title: Senior Director, Land and Resource Management
POC Work Phone: (813) 500-6891
POC Email Address: Russell.Schweiss@mosaicco.com

Alternative Point of Contact (Optional) Company Name/Agency: Mosaic Fertilizer, LLC Project 
Sponsor: Russell Schweiss
Street Address: 13830 Circa Crossing Drive
City: Lithia State: Florida Zip: 33547
POC Name: Shelley Thornton
POC Title: Director, Land Use Permitting
POC Work Phone: (813) 500-6958
POC Email Address: Shelley.Thornton@mosaicco.com

Project Purpose
Please provide a concise overview of the purpose and objective of the proposed project:

Mosaic Fertilizer, LLC (Mosaic) is the country’s largest domestic supplier of phosphate crop nutrients, supplying over half of America’s annual requirements.

After phosphate rock is mined, it must be processed to make it usable by crops. Mosaic processes phosphate ore and manufactures sulfuric acid, phosphoric acid, fluorosilicic acid and ammoniated phosphate fertilizer products. Processing the ore to make phosphate fertilizer results in the 
production of phosphogypsum, a solid waste material that must be stored in an engineered feature known as phophogypsum stack, or “gypstack”. 40 C.F.R. 61.202. The ability to store the phosphogypsum that results from manufacturing fertilizer products is critical to the manufacturing 
process.

At the Riverview Facility in Florida, Mosaic owns and operates the Riverview Fertilizer Manufacturing Plant, two phosphogypsum storage stacks (the now closed West Stack and the currently operating East Stack), and associated infrastructure. The phosphogypsum produced at the Riverview Fertilizer Manufacturing Plant is stored in the East Stack, located to the east of and across U.S. Hwy 41 from the Riverview Fertilizer Manufacturing Plant.

The purpose of the project is to extend the East Stack at the Riverview Fertilizer Facility to provide storage capacity needed to maintain current production levels until the estimated end of life of the Riverview Fertilizer Manufacturing Plant. This, in turn,will allow Mosaic to continue producing vital phosphate crop nutrients to support national and global food production.

Project Description
Please provide a concise description, including the general location of the proposed project and a 
summary of geospatial information, if available, illustrating the project area and the locations, 
if any, of environmental, cultural, and historic resources.

Mosaic is seeking to extend the East Stack on portions of an approximately 307-acre tract of land in Hillsborough County, Florida. An illustration of the planned extension is provided below.

Figure 1-1: Project Site Overview

Mosaic currently operates the East Stack which is expected to reach storage capacity by 2029. The East Stack currently receives phosphogypsum from the Fertilizer Manufacturing Plant.

Location and Environmental Features:
The project area is located north of the Alafia River in Hillsborough County, within the Tampa Bay watershed. The principal land use is heavily industrial. Approximately
11.7 acres of wetlands and 4.5 acres of other surface waters are present onsite.

Mosaic will seek to modify an existing Clean Water Act Section 404 permit to authorize the fill of approximately 16.2 acres of WOTUS preliminarily identified by Mosaic in the project footprint. It requested an Approved Jurisdictional Determination (AJD) on March 4, 2025, to the U.S. Army Corps of Engineers (USACE) and that request remains pending. Impacts to WOTUS will be fully offset through compensatory mitigation in the form of permittee-responsible mitigation projects.

Cultural/Historic Resources:
The ESE area will be surveyed by cultural resource management/archeological experts. Mosaic does not anticipate the project would affect historic properties or other cultural resources due to historical industrial use within the project area.

Technical and Financial Ability
Please provide a description regarding the technical and financial ability of the project sponsor to construct the proposed project

Mosaic’s corporate parent, The Mosaic Company (MosaicCo), is the world’s leading producer and marketer of concentrated phosphate and potash crop nutrients. MosaicCo is a single source supplier of phosphate- and potash-based crop nutrients and animal feed ingredients and serves customers in approximately 40 countries. It is the second largest integrated phosphate producer in the world and one of the largest producers and marketers of phosphate-based animal feed ingredients in North 
America and Brazil. MosaicCo subsidiaries mine phosphate rock in Florida, Brazil, and Peru and processes rock into finished phosphate products at facilities in Florida, Louisiana, and Brazil.

Summary of Financing, Reviews and Authorizations
Please provide a description of any Federal financing, environmental reviews, and authorizations to be required to complete the proposed project.

No Federal financing is required for this project.

CWA 404 Permit – A modification to an existing individual permit will be required from the USACE for discharges of dredged or fill material to waters of the United States pursuant to Section 404 of the Clean Water Act.

NEPA Review – Modification of an individual CWA 404 permit triggers environmental review pursuant to the National Environmental Policy Act (NEPA). An Environmental Assessment likely would be appropriate under NEPA because the project is in a heavily industrial area, and the impacts will be 
fully offset by the proposed mitigation. The USACE will be the lead agency coordinating the NEPA review.

ESA Section 7 Consultation – The project constitutes a major construction activity for which a Biological Assessment (BA) is required pursuant to Section 7 of the Endangered Species Act, and the USACE must initiate consultation with the U.S. Fish and Wildlife Service (USFWS) concerning the application to assess potential impacts to threated and endangered fish and wildlife species and critical habitat. The Federally listed species associated with this project are pygmy fringe-tree, monarch butterfly, American alligator, American crocodile, eastern indigo snake, crested caracara, eastern black rail, Everglades snail kite, rufa red knot, whooping crane, wood stork, tricolored bat, and West Indian manatee. Although the BA has not yet been completed, formal consultation with a Biological Opinion and Incidental Take Statement may be needed for one or more of these species. Coordination between the USACE and the National Marine Fisheries Service (NMFS) pursuant to the Magnuson-Stevens Fishery Conservation and Management Act is also required to determine potential effects on Essential Fish Habitat.

NHPA Section 106 – Upon completion of the cultural resources assessment survey at the project site, Mosaic will seek concurrence from the Florida Department of State, Division of Historical Resources State Historic Preservation Officer (SHPO) on the proposed National Register of Historical Places (NRHP) determinations. Mosaic does not anticipate the project would affect historic properties or other cultural resources due to historical industrial use within the project area.

In addition to the above, Mosaic will obtain all required state and county approvals.

Project Assessment
Assessment that the project meets the definition of a covered project as defined in 42 U.S.C. § 4370m(6)(A) of the FAST Act and a statement of reasons supporting the assessment.

1. Sector Applicability: The ESE project falls within the manufacturing sector.

2. NEPA Applicability: The ESE project is subject to NEPA.

3. Financial Investment: The project will require a total investment of more than $200,000,000.

4. Abbreviated Review Exclusion: The ESE project does not qualify for abbreviated authorization or environmental review processes under any applicable law.

Form Submitter Contact Information Submitter Contact Information
Name: Shelley Thornton
Title: Director, Land Use Permitting
Work Phone: (813) 500-6958
Email: shelley.thornton@mosaicco.com
Agreement
By submitting this application, I affirm that I am an authorized representative of the Sponsor indicated above and that the facts set forth in this form are true and complete.