P R O S P E R I T Y T H R O U G H I N V E S T M E N T

B M O FA R M - TO - M A R K E T C O N F E R E N C E

M AY 1 8 - 1 9 , 2 0 1 6

F O RWA R D - L O O K I N G S TAT E M E N T S

This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including statements about the company’s 2018 vision, including its ability to deliver sales and EBITDA results, build on its essential minerals base, invest in unique assets, drive efficiency, improve its strategies, achieve a balanced business, develop best-in-class safety and transform culture; its expected cash flow; the ability of capital projects to drive growth; growth prospects of Brazil, including its agricultural market, Produquímica Indústria e Comércio, including its expected growth, revenue, sales, EBITDA, growth of its businesses, expected new products, available capacity, leverage ratio and its value creation and return for us; and growth opportunities from Wolf Trax. The company uses words such as “may,” “would,” “could,” “should,” “will,” “likely,” “expect,” “anticipate,” “believe,” “intend,” “plan,” “forecast,” “outlook,” “project,” “estimate” and similar expressions suggesting future outcomes or events to identify forward-looking statements or forward-looking information. These statements are based on the company's current expectations as of the date of our last update, April 25, 2016, and involve risks and uncertainties that could cause the company's actual results to differ materially. The differences could be caused by a number of factors, including (i) weather conditions, (ii) pressure on prices and impact from competitive products, (iii) any inability by the company to fund necessary capital expenditures, (iv) foreign exchange rates, (v) the cost and availability of transportation for the distribution of our products, (vi) the occurrence of any event, change or other circumstance that would result in the termination or delay of the company’s acquisition of the remaining Produquímica ownership stake by early 2019, (vii) the inability to complete the proposed full ownership acquisition due to the failure of the company or Produquímica to satisfy any of the conditions to the closing of the acquisition, including the failure to obtain necessary financing, (viii) the risk that the proposed full ownership acquisition could disrupt the plans and operations of the company, Produquímica or both, and (ix) the risk that the company may not realize the expected financial and other benefits from the proposed acquisition. For further information on these and other risks and uncertainties that may affect our business, see the “Risk Factors” sections of our Annual Report on Form 10-K for the year ended December 31, 2015. The company undertakes no obligation to update any forward-looking statements made in this presentation to reflect future events or developments. Because it is not possible to predict or identify all such factors, this list cannot be considered a complete set of all potential risks or uncertainties.

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2 0 1 5 S A L E S = $ 1 . 1 B I L L I O N

Plant Nutrition 22%

Consumer &

Industrial 30%

Salt Segment 78%

A L E A D E R I N S T R O N G , D I V E R S E M A R K E T S W I T H U N I Q U E A S S E T B A S E

• A leading supplier of deicing mineral products in North America and the U.K.

• Advantaged rock salt mining assets - Largest North American mine strategically

located on deep-water port - Largest dedicated salt mine in the U.K.

• A key producer of high-quality salt for consumers and industry throughout North America

• The largest sulfate of potash (SOP) specialty fertilizer producer in the Western Hemisphere

- One of three low-cost solar pond facilities in the world

• A growing micronutrient business based on patented technology

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Highway Deicing 48%

O U R I N V E S T M E N T T H E S I S

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O U R S A LT B U S I N E S S

• Highway deicing - Rock salt and other deicers sold to

municipal, county and state/provincial governments

- Rock salt sold to chemical producers

• Consumer and industrial - A broad range of non-seasonal packaged

and bulk products Water conditioning Animal nutrition Many industrial applications, including food

- Packaged deicers Basic, blended and premium products

• Advantaged assets - Goderich, Ontario

World’s largest rock salt mine Size and geology enable mining efficiencies Deep-water port and distribution network

support efficient shipping - Winsford, Cheshire, U.K.

U.K.’s largest dedicated rock salt mine Geology and environment support storage

businesses

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Great Britain Salt Production Locations Primary highway deicing markets Underground salt mining Mechanical evaporation Solar evaporation Packaging plant

Salt Segment 2015 Snapshot (in millions)

Sales $849

Adjusted EBITDA* $259

Adjusted EBITDA* margin 31%

Four-year adjusted EBITDA* margin average 26%26% *Non-GAAP measure. See appendix for reconciliation.

SOP Markets & Sites

Headquarters

SOP Production Sites

Ogden, UT

Wynyard, Saskatchewan

O U R P L A N T N U T R I T I O N B U S I N E S S

• Natural, organic-approved SOP from the Great Salt Lake

- Environmentally-friendly, low-cost solar evaporation

- Able to extend production capacity with purchased potassium

• Highest purity SOP in the industry produced in Saskatchewan

- Agricultural, industrial, food and pharmaceutical uses

• Wolf Trax acquired in 2014 to provide growth opportunities in micronutrients

- Applied to more crops and geographies - Strong margin profile

• Now in Brazil with 35 percent stake in Produquímica Indústria e Comércio

- Leading Brazilian specialty plant nutrition company with strong position in micronutrients

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Fruit, Potatoes

Fruit, Vegetables, Nuts, Turf

Fruit, Vegetables, Turf

Turf, Tobacco

*Non-GAAP measure. See appendix for reconciliation.

Plant Nutrition 2015 Snap Shot (in millions)

Sales $238

EBITDA* $88

EBITDA* margin 37%

Four-year adjusted EBITDA margin average 37%

O U R 2 0 1 8 V I S I O N

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BUILD ON ESSENTIAL MINERALS BASE;

DELIVER RESULTS: $1.7+ BILLION IN SALES

$500+ MILLION IN EBITDA

DEVELOP BEST-IN-CLASS SAFETY; TRANSFORM CULTURE

INVEST IN UNIQUE ASSETS OF STRATEGIC IMPORTANCE; DRIVE EFFICIENCY THROUGHOUT OPERATIONS

STRENGTHEN GROW

IMPROVE IMPROVE GO-TO-MARKET STRATEGIES; ACHIEVE MORE

BALANCED BUSINESS

M A J O R C A P E X P R O J E C T S O N T R A C K ; S I G N I F I C A N T C A S H F L O W E X PA N S I O N E X P E C T E D I N 2 0 1 8

8

8

$0

$50

$100

$150

$200

2016 2017 2018Base MOB Special MOB Investment Capital

($ in millions)

2016-2018 Capital Spending Plan

Investment Cost Completion Timing

Percent Complete

Goderich shaft relining (Special MOB)

Ogden plant projects (Special MOB)

Ogden plant expansion (Investment capital)

Goderich continuous mining (Investment capital)

Major Capital Projects On-Track to Drive Growth

$0

$100

$200

$300

2010-2014 Average 2018EPrior to

Investment Plan

Investment Plan Fully Executed**

*Non-GAAP measure. See appendix for reconciliation. ** Excludes any potential benefit from full ownership of Produquímica.

Free Cash Flow* Expectations (in millions)

Dividends Excess Free Cash Flow*

P R O S P E R I T Y T H R O U G H I N V E S T M E N T

PRODUQUÍMICA INVESTMENT • W H Y B R A Z I L ? • W H Y P R O D U Q U Í M I C A ? • AT T R I B U T E S O F T H E B U S I N E S S • G R O W T H P R O S P E C T S • D E A L M E C H A N I C S

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62

161 121 107

157 112

48 43 38 23 36

328 108

99 88

12

26

36 33 33 26 12

Arable Land Unavailable Arable Land Available

W H Y B R A Z I L ? S T R O N G A G M A R K E T F U N D A M E N TA L S ; L O N G - T E R M G R O W T H P O T E N T I A L

• Brazil is a key global agricultural market with opportunity for strong, long-term growth

- Leading country in production of key crops

- Agribusiness represents ~23% of GDP

- Highest potential for growth in agriculture

- Strong fertilizer usage growth

• Nutrient-deficient soil profile requires comprehensive plant nutrient mix to ensure yield

- Brazilian growers increasingly turn to technology-driven solutions

- Specialty product application rates growing at higher rate than NPK fertilizers

• Growing focus of global agriculture companies

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Brazil’s Leading Position in Key Products (2014/2015)

Product

Soy

Coffee

Sugar

Orange

Corn

Meat

Exports

#2

#1

#1

#1

#2

#1

Production

#2

#1

#1

#1

#3

#3

Source: USDA, FAO

Sources: FAO, Embrapa, Conab, MAPA

Abundant Land Available for Cultivation (in hectar millions)

W H Y P R O D U Q U Í M I C A ? L E A D I N G B R A Z I L I A N P L A N T N U T R I T I O N C O M PA N Y W I T H S T R O N G G R O W T H P R O F I L E

• Two growth businesses: - Leading specialty plant nutrition business with

50-year history

- Growing specialty chemicals business focusing on water treatment and process chemicals

• Fundamental to acquisition portion of Compass Minerals $500+ million EBITDA* growth target

• Provides instant access to one of the largest agriculture markets in the world

• Full ownership option in place

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P R O D U Q U Í M I C A S N A P S H O T

2 0 1 5 Headquarters São Paulo, Brazil

Manufacturing Facilities 9

Employees 1,400

Revenue R$1.1 billion

EBITDA* R$184 million

2011-2015 Net Revenue CAGR 16%

2011-2015 EBITDA* CAGR 19%

*Non-GAAP measure. See appendix for reconciliation

S T R O N G S P E C I A LT Y P L A N T N U T R I T I O N B U S I N E S S W I T H B R O A D P O R T F O L I O

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Agriculture 70% of

2015 sales

Jan Feb March April May June July Aug Sept Oct Nov Dec

Soil nutrients: micronutrients, secondary nutrients and other supplements

Technology products: controlled and slow release formulations Micronutrients sold to industry customers

Nutritional supplements for cattle, poultry and dairy cows

R$ 30

R$ 50

R$ 70

R$ 90

R$ 110

R$ 130

2011 2012 2013 2014 2015

EBITDA* Five-year CAGR = 17%

Sales by product category

Seasonality of Shipments (2013-2015 monthly average of shipment volumes)

*Non-GAAP measure. See appendix for reconciliation.

G R O W I N G S P E C I A LT Y C H E M I C A L B U S I N E S S

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Specialty Chemicals

30% of 2015 sales

R$ 20

R$ 35

R$ 50

R$ 65

2011 2012 2013 2014 2015

EBITDA* Five-year CAGR = 24%

Water treatment products and services, including chlore-alkali and derivatives for municipal and industrial clients to treat waste water and control odor

Sales by product category

Process chemicals for broad range of industrial customers, including oil and gas, mining, pulp and paper, and others

Jan Feb Mar Apr May June July Aug Sep Oct Nov Dec

Little Seasonality in Shipments (2013-2015 monthly average of shipment volumes)

*Non-GAAP measure. See appendix for reconciliation.

C O N S U LTAT I V E A G R I C U LT U R E S A L E S F O R C E A N D S T R O N G R & D P L AT F O R M TO D R I V E G R O W T H

• Consultative sales force backed by strong agronomic research and technical skills

- Working to drive sales to value-added product lines

• Strong distribution system throughout key agriculture regions in Brazil

• Over 30 R&D professionals developing new products to respond to grower needs

• Seven new products launched in 2015; eight expected in 2016

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65% DIRECTLY TO FARMS

PLANT NUTRITION SALES

55% of 2015 Revenue from NEW PRODUCTS*

*Includes new products introduced since 2010.

M A C R O D R I V E R S S U P P O R T S P E C I A LT Y C H E M I C A L S O U T L O O K

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• Demand for key products driven by continued population growth and increased urbanization throughout Brazil

• As country continues to modernize, the need for drinking and waste water treatment increases

• Industrial customers also leveraged to economic recovery

- Mining - Oil and Gas - Pulp and Paper

20% population growth expected from

2005 to 2035

Almost ½ population lacks access to sewage

systems

Only 37% of sewage currently

treated

Sources: United Nations and Produquímica.

C A PA C I T Y I N P L A C E TO C A P T U R E C O N T I N U E D G R O W T H

• Investments already made to support future growth in both businesses

• Available capacity expected to support at least four years of growth

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Foliar Sulfurgran Chloralkali &Derivatives

Slow Release Ingredients

Production Capacity

Volume Sold

Available capacity 67%

39% 35% 86% 58%

Volume sold and production capacity of key product lines

S T R O N G P R O S P E C T S F O R G R O W T H

2015 2020

R$ 1.1 billion

• Conservative growth assumption compared to prior five years

• Revenue expected to increase 60% to 80% by 2020

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• EBITDA expected to double by 2020 • Assumes modest margin expansion

2015 2020

R$ 184 million

~12% CAGR

~15% CAGR

EBITDA* Projections

*Non-GAAP measure. See appendix for reconciliation.

Revenue Projections

2017 2018

E X P E C T S T R O N G VA L U E C R E AT I O N F R O M A C Q U I S I T I O N

Current Investment • R$450 million, or approximately 9.5x

TTM adjusted EBITDA, less net debt • Represents 35% of company

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Path to Ownership

Projected Leverage Ratio Expected at Target Level in 2018*

Value Creation • Expected return in line with Compass

Minerals targets • Supports Compass Minerals’ plant nutrition

strategy by providing greater diversity in crops, geographies and specialty products

• Specialty chemical business partially mutes agriculture seasonality

~3.0x

~2.5x

*Assumes Produquímica puts remainder of company to Compass Minerals in 2016, with acquisition closing in 1Q17.

• Produquímica has three options to sell remainder to Compass Minerals: 2017 at 9.4x TTM EBITDA 2018 at 9.3x TTM EBITDA 2019 at 9.2xTTM EBITDA

• Compass Minerals has option to purchase remainder of Produquímica in 2019 for 9.2x TTM EBITDA

C O M P E L L I N G S T E P I N E X E C U T I N G O U R G R O W T H S T R AT E G Y

• Acquisition in key agriculture market underpinned by strong economic and demographic fundamentals

• Leading company with a long history and great management team • Capacity in place to support growth • Potential for company to double EBITDA by 2020

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P R O S P E R I T Y T H R O U G H I N V E S T M E N T

APPENDIX

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R E C O N C I L I AT I O N O F N O N - G A A P I N F O R M AT I O N

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Reconciliation for Free Cash Flow (unaudited) (in millions)

Full Year ended December 31,

2014 2013 2012 2011 2010 GAAP cash flow from operations $ 242.9 $ 238.3 $ 151.7 $ 252.3 $ 241.2

Capital expenditures 125.2 122.7 130.9 107.4 112.1

Free Cash Flow $ 117.7 $ 115.6 $ 20.8 $ 144.9 $ 129.1

R E C O N C I L I AT I O N O F N O N - G A A P I N F O R M AT I O N

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Reconciliation for Salt Segment EBITDA and Adjusted EBITDA (unaudited) (in millions)

12 months ended December 31,

2012 2013 2014 2015 Segment sales $ 703.4 $ 920.5 $ 1,002.6 $ 849.0

Segment operating earnings 126.0 181.3 291.4 215.2 Depreciation, depletion and

amortization 38.9 45.1 44.8 43.9

Segment EBITDA $ 164.9 $ 226.4 $ 336.2 $ 259.1

Adjustments to EBITDA:

Estimated cost of legal ruling(1) - 4.7 - -

Gain from insurance settlement(2) - - (82.4) - Adjusted segment EBITDA $ 164.9 $ 231.1 $ 253.8 $ 259.1

Adjusted segment EBITDA margin 23.4% 25.1% 25.3% 30.5%

(1) In 2013, the company recorded a reserve of $4.7 million related to a ruling against the company from a 2010 labor issue. (2) In the third quarter of 2014, the company reported a gain from an insurance settlement relating to damage sustained by the company as a result

of a tornado that struck the company’s rock salt mine and evaporated-salt plant in Goderich, Ontario.

R E C O N C I L I AT I O N O F N O N - G A A P I N F O R M AT I O N

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Reconciliation for Plant Nutrition Segment EBITDA (unaudited) (in millions)

12 months ended December 31,

2012 2013 2014 2015

Segment sales $ 226.2 $ 198.6 $ 270.2 $ 238.4

Segment operating earnings 58.4 58.7 74.8 57.9

Depreciation, depletion and amortization 21.4 23.8 27.3 29.8

EBITDA $ 79.8 $ 82.5 $ 102.1 $ 87.7

Adjustments to EBITDA: Gain from insurance settlement - (9.0) - -

Adjusted Segment EBITDA $ 79.8 $ 73.5 $ 102.1 $ 87.7

Adjusted Segment EBITDA Margin 35.3% 37.0% 37.8% 36.8%

(1) In 2013, the company reported a $9.0 million gain from an insurance settlement resulting from a 2010 brine loss at the company’s Ogden, Utah, solar-pond facility.

R E C O N C I L I AT I O N O F N O N - G A A P I N F O R M AT I O N

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Reconciliation for Produqímica EBITDA (unaudited) (in R$ millions)

Twelve months ended December 31,

2011 2012 2013 2014 2015

Company operating earnings $ 75.3 $ 78.6 $ 100.6 $ 93.8 $ 145.0

Depreciation, depletion and amortization 16.4 18.6 20.2 29.7 38.9

EBITDA $ 91.7 $ 97.2 $ 120.8 $ 123.5 $ 183.9

Reconciliation for Produqímica Agriculture Business EBITDA (unaudited) (in R$ millions)

Twelve months ended December 31,

2011 2012 2013 2014 2015 Agriculture operating earnings $ 58.8 $ 63.1 $ 72.1 $ 58.6 $ 99.7 Depreciation, depletion and amortization 6.0 8.3 9.7 18.0 21.5 EBITDA $ 64.8 $ 71.4 $ 81.8 $ 76.6 $ 121.2

Reconciliation for Produqímica Specialty Chemical Business EBITDA (unaudited) (in R$ millions)

Twelve months ended December 31,

2011 2012 2013 2014 2015

Specialty Chemicals operating earnings $ 16.5 $ 15.5 $ 28.5 $ 35.3 $ 45.3

Depreciation, depletion and amortization 9.3 9.2 9.0 10.0 15.5

EBITDA $ 25.8 $ 24.7 $ 37.5 $ 45.3 $ 60.8