New Wales Water Loss Incident
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New Wales Water Loss Incident

This page will provide frequent updates on a sinkhole that formed in one compartment of Mosaic’s active gyp stack in New Wales. Questions may be directed to Callie Neslund at (863) 844-5327. The number to call for inquiries about testing or bottled water is (813) 500-6575 or you can email us at

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April 21, 2017 Report

Partner Spotlight: Moretrench

Several contractors and consultants are bringing specialized skills and expertise to help Mosaic Fertilizer repair the sinkhole. This partner spotlight series will highlight those firms and their efforts.

Moretrench, a leading geotechnical and construction company, has nearly 20 years’ experience supporting gypstack operations at New Wales, making it well-positioned to help as we repair the sinkhole. Moretrench is based in Florida, and has more than six employees onsite at New Wales.

During the sinkhole repair process, the Moretrench team has helped Mosaic Fertilizer analyze, design, and implement solutions to complex challenges. Among other things, Moretrench was instrumental in constructing a system to place LIDAR and other survey equipment in the sinkhole. They also built the work pad on and access roads to the gypstack, which allowed us to deploy a host of large and heavy, specialty equipment. Through those efforts, we moved more than 700,000 cubic yards of material.

Through its 120 year history, Moretrench has earned a strong reputation in the civil, environmental, construction and geotechnical engineering communities for its emphasis on safety, innovation and service. We are pleased to have them on the team.

April 20, 2017 Report

Defining the Terms – Piezometer

This series will further explain some of the technical terms used in our remediation posts.

This post defines the term “piezometer” which we use when referring to monitoring instruments in the gypstack.

A piezometer is a commonly used instrument to monitor subsurface water levels. Mosaic Fertilizer is using two types of piezometers at New Wales, standpipe piezometers and vibrating wire piezometers, to measure the water levels in and around the gypstack. As the deeper, higher pressure grouting progresses, the piezometers will show an increase in water levels, indicating the confining layer is being repaired. Pictured below are two piezometers installed at New Wales back in February 2017.

April 14, 2017 Report

Web Updates Will Resume Next Week

Updates to the New Wales Water Loss Incident page will resume the week of April 17, 2017.

We hope everyone has a wonderful holiday.

An aerial view of New Wales and the ongoing remediation activities.

April 14, 2017 Report

Partner Spotlight: Ardaman & Associates, Inc.

Several contractors and consultants are bringing specialized skills and expertise to help Mosaic Fertilizer repair the sinkhole. This partner spotlight series will highlight those firms and their efforts.

Repairing the sinkhole is a unique, complicated effort which requires specialized skills and expertise to complete it safely, effectively and efficiently. Ardaman & Associates, a geotechnical engineering consultancy, has a long history working on projects in the phosphate industry in Florida, making it especially suited to help Mosaic Fertilizer repair the sinkhole.

For almost 60 years, Ardaman has provided engineering services to the industry around the world, and worked on more than 70 gypstack projects on six continents.

Ardaman professionals are working alongside Mosaic Fertilizer to evaluate, design and implement many of the steps underway to aid in repairing the sinkhole. For example, they reviewed LiDAR and other survey data collected to define the extent of the cavity and assess the drilling and grouting efforts. Ardaman has also defined the safety perimeter and supported the installation of monitoring instrumentation in the gypstack.

Beyond its role in responding to the sinkhole, Ardaman helps design gypstacks and develops water management plans for these systems.

Ardaman is viewed by the industry and by regulators as a leading engineering resource working in the phosphate industry. In fact, its senior consultants have been appointed by the State of Florida to serve on the Technical Advisory Committees that assisted the FDEP in developing the Florida Administrative Code rules pertaining to the design and operation of gypstacks and related features.

April 7, 2017 Report

Mosaic Utilizing Company-wide Talent to Support Sinkhole Repairs

A safety specialist from Mosaic’s Esterhazy potash mine is taking her knowledge and experience from Canada to Florida for six months.

Jacki Hilts is on a temporary assignment to support her colleagues repairing the sinkhole.

She was selected because of her extensive experience supporting underground potash mining, which can include large scale drilling and grouting projects.

“This assignment is a great example of sharing talent across the company to work on projects that are critical to our business,” said Mosaic Director, EHSS-Potash, Holland Thompson.

In her new role, Hilts will be the Mosaic contact for all contract partners working on the grouting project.

Hilts said she is working closely with the contract partners to implement safety controls, further align their safety programs with Mosaic’s and consult on safety-related questions.

“I have been fortunate enough to work at the Esterhazy K2 mine for quite a while and have witnessed the strong safety culture there,” Hilts explained. “I am taking what I learned in Esterhazy and applying it here at New Wales.”

April 5, 2017 Report

A View from Above

On top of the gypstack, Mosaic Fertilizer crews and contractors continue to drill angled holes and inject grout to repair the sinkhole.

March 31, 2017 Report

Various Engineering Disciplines Repairing the Sinkhole

Engineers solve problems. They use special skills, learned knowledge and hands on expertise to identify and implement solutions. Whether you are constructing a bridge, a tunnel or repairing a sinkhole – it’s important to have the right people onsite to get the job done safely and efficiently.

Mosaic Fertilizer is fortunate to have some of the brightest minds – electrical engineers, process engineers, project engineers, civil engineers and more – all working together to repair the sinkhole.

Remediation Activities

A Mosaic Fertilizer civil engineer is the project manager for the remediation activities on the gypstack. Civil engineers are trained to deal with the design, construction, and maintenance of built structures, making them the ideal personnel to oversee the sinkhole repairs, including the earth work, drilling and grouting, while accounting for safety and compliance with regulatory standards.

Electrical and Instrumentation

At New Wales, the electrical engineers are responsible for designing, installing and maintaining the electrical and instrumentation systems onsite. Among other roles, the electrical engineers at New Wales managed the design, installation and ongoing operation of the electrical components in the recovery well, including the recovery well pump motor, flow meters and other components.

Water Treatment

Process engineers design and optimize various processes. Project engineers schedule, prepare and plan projects, procure needed resources and supervise construction. Mosaic Fertilizer’s process and project engineers worked together to design the treatment and distribution system, and identify and coordinate the vendors to build the system.

These engineers only represent a portion of the professionals working daily to repair the sinkhole safely and effectively. Mosaic Fertilizer is very proud to have such committed and skilled team members working together to address complex engineering challenges.

March 30, 2017 Report

Video Update: Drilling and Grouting

Drilling and grouting is a complex process with multiple steps, requiring Mosaic Fertilizer to produce a concrete-like mixture, known as grout, from an onsite batch plant, drill multiple angled holes to different depths in the gypstack, and inject grout at high pressure to repair the base of the sinkhole. The video below provides a glimpse of these and other efforts happening onsite.

 March 24, 2017 Report

Your Questions and Our Answers

Questions from the community are very important to us. Mosaic Fertilizer will be using the New Wales web page to answer frequently asked questions.

Q: Neighbors have been asking Mosaic Fertilizer to explain how we’ll know the breach in the confining layer, caused by the sinkhole, has been repaired.

Mosaic Fertilizer poured grout in the sinkhole above the confining layer for stabilization purposes. The deeper high pressure grouting will repair the breach in the confining layer. When those efforts are complete, data from monitoring instruments will confirm changes to water levels in the gypstack. Increasing levels will indicate that the breach has been repaired.

March 22, 2017 Report

Update on First Quarter 2017 Well Sampling for Residents within a Four Mile Radius

Environmental Consulting & Technology, Inc. (ECT) is completing the first quarter 2017 well sampling program for residents within a four mile radius of the sinkhole who have requested that sampling.

A few residents who have had their wells previously sampled and qualify for re-testing have not responded to requests to arrange for sampling in the first quarter. Those residents are encouraged to contact Mosaic Fertilizer at (813) 500-6575 by March 24, 2017 to arrange for sampling this quarter.

Private drinking water wells continue to show no impacts from the sinkhole.

March 17, 2017 Report

Management of Recovered Water

Mosaic Fertilizer continues to treat recovered water at the New Wales facility. The first and second phases of the treatment system were commissioned in December 2016 and February 2017, respectively. The system treats impacted water collected from the recovery well by ultrafiltration and reverse osmosis, and complements Mosaic Fertilizer’s existing water management practices.

March 15, 2017 Report

Defining the Terms – Grout

This series will further explain some of the technical terms used in our remediation posts.

This post defines the term: grout, which we use when referring to sinkhole repairs.

Mosaic Fertilizer is drilling angled holes to inject grout that will ultimately repair the sinkhole. Grout mix is a concrete-like material made onsite at New Wales which includes cement, two types of sand and pea gravel.

Currently, Mosaic Fertilizer plans to produce four different grout mixes. Like a recipe in a cookbook, grout must be made with the right amount of each material to achieve the right properties. For example, grout mix previously used to stabilize the upper cavity has different specifications than the grout mix that will be used during the deeper grouting to repair the sinkhole.

In support of these efforts, Mosaic Fertilizer commissioned the onsite batch plant in January 2017. Once the plant was operational, trial mixes (test batches of grout mix) were produced until they met the project specifications.

After the grout is prepared, water and clay are added for lubrication. It is then loaded into a concrete truck where it is mixed for use.

March 10, 2017 Report

Operations Update on Well Installation and Sinkhole Repairs

P-5 Standby Recovery Well Installation

Mosaic Fertilizer successfully installed the P-5 recovery well which is located approximately one-half mile west of the sinkhole. P-5 was installed in accordance with the Consent Order and will provide additional recovery capacity if needed. P-4B remains the only recovery well in operation.

Grouting Update and LiDAR Redeployment

Over the last several weeks, Mosaic Fertilizer deposited more than 10,000 cubic yards of grout to stabilize the upper cavity of the sinkhole. This week, the LIDAR system and other assessment tools were deployed to assess those grouting efforts. The data collected will be used to refine the location of the deeper, high-pressure grouting holes which will be used to repair the base of the sinkhole.

March 7, 2017 Report

Following Through on Our Commitment to Repair the Sinkhole

Tremendous efforts have been made to repair the sinkhole at New Wales. Just last month, Mosaic Fertilizer started the initial phase of grouting, installed additional instrumentation to measure water levels in the gypstack, and commissioned a new recovery well, P4B. And last week, members of the local media were invited to the New Wales facility to review progress and visit the work pad on top of the gypstack. The short video below highlights important steps Mosaic Fertilizer has taken to respond to the sinkhole, and provides additional footage from the recent media tour of the gypstack.

Having trouble viewing the video? Click here.

March 2, 2017 Report

Key Steps in Responding to the 2016 Sinkhole

Mosaic Fertilizer has been diligently working to repair the sinkhole. The “Key Steps in Responding to the 2016 Sinkhole” infographic below provides a snapchat of these efforts. You can also download it here:

February 28, 2017 Report

Listening to our Community

Answering questions from the community is very important to Mosaic Fertilizer. Come here often to see how we are addressing frequently asked questions.

Q: Where was the 1994 sinkhole and how was it repaired?

In 1994, the now-closed north New Wales gypstack experienced a sinkhole. IMC, Mosaic’s predecessor, remediated the sinkhole through a grouting process, and those activities were subject to the oversight of regulatory agencies.

In the years since that incident, Mosaic Fertilizer has monitored the area where the sinkhole occurred. We continue to collect groundwater data and provide monthly reports to FDEP and Polk County.

The monitoring system which was installed following that event proved its effectiveness in 2013 when it indicated a water level drop in the north gypstack. Those measurements prompted the company to investigate, and we learned that a two to three foot-wide sub-surface erosion channel had developed in the vicinity of the 1994 sinkhole. The erosion channel was then filled with grout injected at high pressure.

The groundwater monitoring data downgradient from the 1994 sinkhole location now spans more than two decades and continue to show no signs of offsite impact and continued improvement in water quality.

We’ve learned a great deal from the 1994 incident and are supplementing that knowledge with new technologies such as LiDAR to expedite the remediation and hone our grouting methods. Extensive site-specific data at and near the New Wales site have also been used to calibrate groundwater flow models, aiding in our understanding of the water flow in the aquifer towards the recovery well.

February 24, 2017 Report

Recovery Well P-4B Zone of Capture

The below graphic illustrates the modeled zone of capture for the new recovery well, P-4B, which is located immediately west of the sinkhole and is directly in line with groundwater flow in the Floridan aquifer.