Calcium Carbonate Supply Chain - Executive Summary

Calcium Carbonate (Limestone)

Rw Material Direct Use Chemical Precursor Chemical

CdC03
(solid)

Source of Raw Material:
Naturally occurring rock

% of Total Domestic Consumption
Attributed to Water Sector:

Less than 1%

^ Derivative Water Treatment Chemicals: dib Understanding Chemical Supply Chains

Map of Suppliers & Manufacturers

Calcium Oxide

— RISK OF SUPPLY DISRUPTION (Assessed in 2022)

Product Family:
Calcium

CAS No.: 1317-65-3

^ Shelf Life:
60+ Months

RISK RATING: Low



RISK DRIVERS

Use of calcium carbonate
(limestone) in construction
aggregate is the leading do-
mestic use. Increases or
decreases in demand for
construction aggregate may
periodically impact the
availability and price, howev-
er calcium carbonate
resources are abundant.

RISK PARAMETERS
Criticality: High. Essential for pH and
alkalinity adjustment, and production of
water treatment chemicals.

Likelihood: Low. The water sector has
not experienced calcium carbonate sup-
ply disruptions between 2000 and 2022.

Vulnerability: Low. The U.S. is a leading
producer of calcium carbonate. It is
abundant and production is widely
distributed.

PRODUCTION PROCESS

Water Treatment Applications

Mining

Calcium Carbonate

•	pH and alkalinity adjustment

•	Water treatment chemical production

Other Applications

Input

End Use

•	Construction aggregate

•	Cement

•	Lime manufacturing

•	Chemical manufacturing

DOMESTIC PRODUCTION AND CONSUMPTION, AND INTERNATIONAL TRADE

Domestic Production Locations (2015):

1,960, widely distributed across 45 states.

(^) International Trade (2019)

Primary Trading Partner (Imports): Mexico
Primary Trading Partner (Exports): Canada

Domestic Consumption (2018):
930,030 M kg

¦	Domestic Production (917,000 M kg)

¦	Imports for Consumption (13,181 M kg)

¦	Export of Domestic Production (500 M kg)

&EPA


-------
Calcium Carbonate Supply Chain - Full Profile

Product Description

Calcium carbonate (CaC03), found in natural deposits as the chief component of limestone, is an abundant,
naturally occurring mineral. Calcium carbonate is used directly in water treatment for pH and alkalinity
adjustment, and also as an input in the manufacturing of calcium oxide (quicklime). The most common domestic
use is in construction aggregate.

Use in Water Treatment

Calcium carbonate is used directly in water treatment for adjustment of pH and alkalinity.

Use as a Precursor to Other Water Treatment Chemicals
Calcium carbonate is used to manufacture calcium oxide.

Other Applications

Calcium carbonate, more commonly referred to by the rock bearing large amounts of calcium carbonate,
limestone, has a wide range of applications. The leading domestic uses are in construction aggregate (roads,
roofing, etc.) and Portland cement production. It is also widely used in pharmaceutical manufacturing, calcium
oxide (quicklime) manufacturing, toothpaste, paint, glass, soil amendment, and foods (USGS, 2012; USGS 2022).

Primary Industrial Consumers

In 2018, approximately 72% of domestically consumed limestone was used as construction aggregate, 16% for
cement manufacturing, 8% for calcium oxide and calcium hydroxide manufacturing, 3% for miscellaneous uses,
and 2% for agricultural uses (USGS, 2021).

Manufacturing, Transport, & Storage

Manufacturing Process

In its natural form calcium carbonate occurs as limestone, a rock containing at least 50 % calcium carbonate. In
2018, approximately 75% of domestic crushed stone produced was limestone (USGS, 2022).

Limestone deposits are found throughout the world, and are recovered by quarrying or mining. Generally,
limestone is crushed to break the rock into the desired size, then screened, washed, and classified. Grain size,
shape, color, structure, and content differ based on deposit location dictate how limestone is processed and the
applications after mining. Limestone may be used as dimenions stone in large pieces, crushed stone in a variety
of applications depending on the grain size, and calcined for use in cement, bricks, steel making, and calcium
oxide manufacturing (DOE, 2013; USGS, 2012; USGS, 2022).

Product Transport

Limestone is commonly transported by rail, truck, and waterway. Though extensive deposits are found
throughout the U.S., there are areas without local access to quarries, and transportation costs may significantly
increase the cost of the delivered product (USGS, 2012; USGS, 2022).

Storage and Shelf Life

Ground limestone is stable and non-reactive over a wide range of temperatures. When stored properly,
limestone can have a shelf life in excess of 60 months (Mississippi Lime, 2015).

EPA 817-F-22-015 | December 2022

xvEPA


-------
Calcium Carbonate Supply Chain - Full Profile

Domestic Production & Consumption

Domestic Production

Production data was collected from USGS, while trade data was collected from the U.S. International Trade
Commission (USITC) Dataweb, as shown in Table 1. Both production and trade data are specific to limestone.

Table 1. Calcium Carbonate Production and Trade Data Sources

Production and Trade Data

Category

Data Source

Identifier

Description

Domestic Production

U.S. Geological Survey

CAS No.: 1317-65-3

Limestone

Imports and Exports

International Trade Statistics
U.S. International Trade Commission

HS Code: 2517.10
HTS Code: 2517.10.0020

Crushed Stone
Limestone

Total U.S. domestic production of limestone was approximately 917,000 million kilograms (M kg) in 2018 (USGS,
2022). Domestic commercial production took place at 1,960 quarries across 45 states. Top producing states in
2018 were Texas, Florida, Ohio, Missouri, and Pennsylvania, which collectively accounted for 46% of all domestic
production (USGS, 2022).

Domestic Consumption

U.S. consumption of limestone in 2018 is estimated at 930,030 M kg. This estimate includes production of
917,000 M kg, import of 13,181 M kg, minus export of 500 M kg (USGS, 2022; USITC, 2021), as shown in Figure 1.
National consumption dominates use of domestically produced limestone. As of 2012, the U.S. consumed
between 5 and 10% of global limestone production (USGS, 2012)

• Domestic Consumption (2018):

930,030 M kg

¦	Domestic Production (917,000 M kg)

¦	Imports for Consumption (13,181 M kg)

¦	Export of Domestic Production (500 M kg)

Figure 1. Domestic Production and Consumption of Limestone in 2018

Trade &Ta riffs

Worldwide Trade

Worldwide import and export data for limestone are reported through the World Bank's World Integrated Trade
Solutions (WITS) software, as a category encompassing all crushed stone, including limestone. In 2021, the U.S.
ranked 43rd worldwide in total exports and first in total imports of crushed stone. In 2021, United Arab Emirates
ranked first worldwide in total exports (WITS, 2022), as shown in Table 2.

2

SEPA


-------
Calcium Carbonate Supply Chain - Full Profile

Table 2. WITS Worldwide Export and Import of Crushed Stone in 2021

2021 Worldwide Trade
Crushed Stone (HS Code 2517.10)

Top 5 Worldwide Exporters

Top 5 Worldwide Importers

United Arab Emirates

33,660 M kg

United States

17,332 M kg

Norway

25,829 M kg

Qatar

15,629 M kg

Oman

22,745 M kg

Flong Kong

11,826 M kg

China

11,620 M kg

Netherlands

11,270 M kg

Indonesia

9,709 M kg

Russian Federation

6,931 M kg

Domestic Imports and Exports

Domestic import and export data are reported by USITC in categories specific to limestone. Figure 2
summarizes imports for consumption1 and domestic exports2 of limestone between 2015 and 2020. During this
period, the overall quantity of exports and imports remained relatively steady, with the volume of imports
considerably larger than the volume of exports. Over this five-year period, Canada was the primary recipient of
domestic exports while Mexico was the primary source of imports (USITC, 2021).

Domestic Trade of Limestone

16'000	HTS Code: 2517.10.0020

14,000

I I	I	I	I	I	I

CO	CO	Oil/)	l/l CO	CO CO	CO CO	CO CO

r	r.	r r	r r	r r	nr.	t r.

oo	oo	oo	oo	oo	oo

CL	Q_	Q.Q.	Q.Q.	Q.Q.	Q.Q.	Q.Q.

c	x	c x	c x	cx	cx	cx

C	ijj	SZ ijj	C ijj	C ijj	d Lij	^ IjJ

(/) CO CO CO CO CO

r r. r r r r

o o o o o o

Q- Q. CL Q. Q_ Q.

C X C X f= X

C uj C ijj C i i I

Imports |
Exports |

Imports |
Exports

Imports |
Exports

2015 2016 2017

2018 2019 2020

¦ Imports from Mexico

¦ Exports to Canada

¦ Imports from Bahamas

¦ Exports to Bahamas

¦ Imports from Other Countries

Exports to Other Countries

Figure 2. USITC Domestic Import and Export of Limestone between 2015 and 2020

1	Imports for consumption are a subset of general imports, representing the total amount cleared through customs and entering
consumption channels, not anticipated to be reshipped to foreign points, but may include some reexports.

2	Domestic exports are a subset of total exports, representing export of domestic merchandise which are produced or manufactured in
the U.S. and commodities of foreign origin which have been changed in the U.S.

3

oEPA


-------
Calcium Carbonate Supply Chain - Full Profile

Tariffs

Imports of limestone are primarily supplied from Mexico. There is no general duty for import of limestone,
however there is an additional 25% duty on imports from China (USITC, 2022), as summarized in Table 3.

Table 3. 2020 Domestic Tariff Schedule for Limestone

HTS Code

General Duty

Additional Duty-China
(Section 301 Tariff List)

Special Duty

2517.10.0020

None

25%

None

Market History & Risk Evaluation

History of Shortages

The most significant current domestic use of limestone is for construction aggregate. This application accounts
for the consumption of the majority of domestically produced limestone. Increases or decreases in demand from
the construction industry may periodically impacted the availability and price of limestone, however limestone
resources are abundant and there were no identified limestone supply chain disruptions between 2000 and
2022.

Risk Evaluation

The complete risk assessment methodology is described in Understanding Water Treatment Chemical Supply
Chains and the Risk of Disruptions (EPA, 2022). The risk rating is calculated as the product of the following three
risk parameters:

Risk = Criticality x Likelihood x Vulnerability
Criticality Measure of the importance of a chemical to the water sector

Likelihood Measure of the probability that the chemical will experience a supply disruption in the
future, which is estimated based on past occurrence of supply disruptions

Vulnerability Measure of the market dynamics that make a chemical market more or less resilient to
supply disruptions

The individual parameter rating is based on evaluation of one or more attributes of the chemical or its supply
chain. The ratings and drivers for these three risk parameters are shown below in Table 4.

4

oEPA


-------
Calcium Carbonate Supply Chain - Full Profile

Table 4. Supply Chain Risk Evaluation for Calcium Carbonate

Risk Parameter Ratings and Drivers



1 1

1

ICriticality High

1 Likelihood Low 1

Vulnerability Low 1

Calcium carbonate is essential and has
widespread application in pH and
alkalinity adjustment. It is a precursor
in the production of other water
treatment chemicals.

The water sector has not experienced
calcium carbonate supply disruptions
between 2000 and 2022.

The U.S. is a leading worldwide
producer of calcium carbonate.
Calcium carbonate is abundant and
production is widely distributed.

Risk Rating: Low

° i

ve-Low Moderaf

RanSe 'e/>

fe.

•JO
an



References

EPA, 2022. Understanding Water Treatment Chemical Supply Chains and the Risk of Disruptions, retrieved
from https://www.epa.gov/waterutilitvresponse/risk-disruptions-supplv-water-treatment-chemicals
Mississippi Lime, 2015. Shelf Life of Mississippi Lime Products, retrieved from

https://www.mississippilime.com/wp-content/uploads/2015/02/Shelf-Life-of-Products-June-2015.pdf
U.S. Department of Energy (DOE), 2013. Energy and Environmental Profiles of the U.S. Mining Industry,
Chapter 9: Limestone and Crushed Rock, retrieved from
https://www.energy.gov/sites/prod/files/2013/ll/f4/stone.pdf

U.S. Geological Survey (USGS), 2012. Limestone - A Crucial and Versatile Industrial Mineral Commodity,
retrieved from https://pubs.usgs.gov/fs/2008/3089/

U.S. Geological Survey (USGS), 2021. 2017 Minerals Yearbook: Stone, Crushed, retrieved from

https://pubs.usgs.gov/periodicals/mcs2020/mcs202Q-stone-crushed.pdf
U.S. Geological Survey (USGS), 2022. 2018 Minerals Yearbook: Stone, Crushed, retrieved from

https://pubs.usgs.gov/mvb/voll/2018/mvbl-2018-stone-crushed.pdf
U.S. International Trade Commission (USITC), 2021. Harmonized Tariff Schedule (HTS) Search, retrieved from
https://hts.usitc.gov/

U.S. International Trade Commission (USITC), 2022. USITC DataWeb, retrieved from

https://dataweb.usitc.gov/

World Integrated Trade Solutions (WITS), 2022. Trade Statistics by Product (HS 6-digit), retrieved from
https://wits.worldbank.org/trade/countrv-bvhs6product.aspx?lang=en#void

5

oEPA


-------