Slag—Iron and Steel—2004 69.

Slag—Iron and Steel

By Hendrik G. van Oss

Ferrous slags are produced by adding slagging agents (chiefly 

limestone or dolomite) and/or fluxing materials to blast furnaces 

and steel furnaces to strip the impurities from iron ore, steel 

scrap, and other iron or steel feeds. The molten slag forms as a 

liquid silicate melt that floats on top of the molten crude iron or 

steel and is tapped from the furnace separately from the liquid 

metal. After cooling, the slag is processed and may then be 

sold. Sales of iron and steel slags in the United States in 2004 

totaled about 21.2 million metric tons (Mt), up by 7.6% from 

sales in 2003; the overall value of sales in 2004 was about $328 

million, up by almost 11% (table 1).

Most slags have very low unit values compared with those 

of pig iron and steel products. Iron and steel companies, 

accordingly, consider the slag they produce to be a nuisance and 

generally contract with outside slag-processing companies to 

remove it; the slag-processing company may also be responsible 

for cooling the slag. Although the financial arrangements vary, 

typically the processing company receives the cooled slag for 

free, crushes it to various marketable sizes, uses screens and 

magnetic separators to recover entrained metal from the slag 

(this metal to be returned to the furnace for a low charge), sells 

the slag on the open market, and pays a small percentage of the 

net slag sales revenues or profits to the iron or steel company. 

Also, slag may be returned to the furnaces for use as flux and as 

a supplemental source of iron; this return of slag is typically not 

reported as a sale.

A list of slag processors, processing sites, and the iron and 

steel companies serviced is provided in table 4. Apparent 

duplication at some sites is explained by the fact that certain 

processing contracts were transferred to other companies during 

the year and the fact that integrated iron and steel plants may 

have contracts with different processing companies for different 

slag types produced at the plant. In some cases, the slag is 

cooled by one processing company and then is further processed 

and sold by another. Apart from a number of contract transfers 

among processing companies, there was a major consolidation 

in the slag-processing industry when, in December, International 

Mill Services, Inc. (IMS) merged with Tube City LLC [the 

parent company of Olympic Mill Services (OMS)]. After 

the merger, IMS was renamed Tube City-IMS, IMS Division, 

and OMS was renamed Tube City IMS Corp. In November, 

Civil & Marine, Inc. began producing ground granulated blast 

furnace slag (GGBFS) at the company’s new grinding plant at 

Cape Canaveral, FL; all of the unground feed for the plant is 

imported.

Legislation and Government Programs

Demand for slag in the construction sector is influenced by 

Federal and State programs that affect construction spending 

levels. The main Federal funding program of this type 

continued to be the Transportation Equity Act for the 21st 

Century (TEA-21). Funding under the TEA-21 in 2004 was 

through temporary continuations of the Act; both houses of 

Congress proposed reauthorizing the Act during the year, but 

had not reached agreement as to the total funding levels by 

yearend. Slags are promoted as “sustainable” construction 

materials, and slag sales benefit from programs that promote use 

of such materials in construction projects. In this respect, the 

attributes cited for slag include the fact that it substitutes directly 

or indirectly for virgin raw materials (for example, natural stone 

aggregates in various applications and natural raw materials for 

cement manufacture). Through its role as a partial substitute 

for portland cement in concrete, GGBFS reduces the unit 

carbon dioxide emissions associated with the concrete; also, the 

GGBFS generally enhances the durability of the concrete.

Production

Blast furnace slags, as sold, are of three main types: aircooled, granulated, and pelletized (or expanded). Air-cooled 

blast furnace slag is formed by allowing the molten slag to cool 

relatively slowly under ambient conditions; final cooling can be 

accelerated with a water spray. The cooled material is hard and 

dense, although it can have a vesicular texture with closed pores. 

After crushing and screening, air-cooled slag is used mainly as 

an aggregate for various purposes (table 3). Granulated slag is 

formed by quenching molten slag in water to form sand-sized 

particles of glass. The disordered structure of this glass gives 

the material moderate hydraulic cementitious properties when 

very finely ground into GGBFS, but if it can access free lime, 

the GGBFS develops strong hydraulic cementitious properties. 

Pelletized or expanded slag is cooled through a water jet, 

which leads to rapid steam generation and the development of 

innumerable vesicles within the slag. The vesicular texture 

reduces the overall density of the slag and allows for good 

mechanical binding with hydraulic cement paste. Blast furnace 

slag (generally air-cooled) also can be made into mineral wool. 

Slag for this purpose is remelted and then poured through an air 

stream or jet of steam or other gas to produce a spray of molten 

droplets; alternatively, the droplets can be formed by passing 

the melt through a perforated or fast spinning disc. The droplets 

elongate into long fibers that are collected and layered.

Steel furnace slag is cooled similarly to air-cooled blast 

furnace slag, has similar properties to it, and is used for many 

of the same purposes. Steel slags containing large amounts of 

dicalcium silicate are prone to expansion and commonly are 

cured in piles for some months to allow for this and for leaching 

out of lime.

Data are generally unavailable from plants on the actual 

output of iron and steel slags for an extended series of 

production cycles (heats). This generally is because not all of 

the slag is tapped during a heat, and the amount of slag tapped 

is not routinely measured. Accordingly, there are no data on 
69. u.s. geologicAl survey minerals yearbook—2004

U.S. production of ferrous slags and few, if any, data on foreign 

production, although both can be estimated based on typical 

slag to metal production ratios, which in turn are related to the 

chemistry of the ferrous feeds to the furnaces. For typical iron 

ore grades (60% to 66% iron), a blast furnace will normally 

produce about 0.25 to 0.30 metric ton (t) of slag per ton of 

crude iron. For ore grades lower than average, the slag output 

will be higher—sometimes as much as 1.0 to 1.2 t of slag per 

ton of crude iron. Steel furnaces typically produce about 0.2 

t of slag per ton of crude steel. However, up to 50% of the 

molten steel slag is entrained metal, most of which is generally 

recovered during slag processing and returned to the furnace. 

The amount of marketable slag remaining after entrained steel 

removal is usually equivalent to about 10% to 15% of the crude 

steel output. Using these ratios and data for U.S. and world iron 

and steel production from the American Iron and Steel Institute 

(2004, p. 125-138), it was estimated that U.S. blast furnace slag 

production in 2004 was in the range of about 12 to 14 Mt, and 

world output was in the range of 200 to 240 Mt. Likewise, U.S. 

output of steel slag (after metal removal) in 2004 was estimated 

to be 11 to 16 Mt, and world output, 115 to 175 Mt.

Consumption

Data in this report are based on an annual U.S. Geological 

Survey (USGS) canvass of slag processors and relate to sales 

of processed slag rather than to the amount of slag processed 

by the same firms or to the actual production of slag by iron 

and steel companies. Processed slag is sold from stockpiles, 

and although most of the material is a byproduct of current or 

recent iron and steel production or is of imported material, some 

is material mined from old slag piles (slag banks) and reflects 

iron and steel production from plants now closed. In 2004, 

canvasses were sent to 28 processing companies, covering 130 

processing sites, and at least partial data were received for 126 

sites. The reported data account for about 98% of the gross 

tonnage for 2004 in table 1. In 2003, surveys were sent to 24 

processing companies, covering 128 processing sites, and at 

least partial data were received for 126 sites. The reported data 

accounted for 99.9% of the gross tonnage for 2003. For both 

years, data are presented only for air-cooled and granulated blast 

furnace slags, as well as steel slag. Data on pelletized slag have 

been withheld for proprietary data protection reasons, but the 

quantities sold were very small; prior to 2002, pelletized data 

were presented combined with granulated slag under the term 

“Expanded slag.”

In terms of tonnage, U.S. slag sales in 2004 continued to be 

dominantly of air-cooled blast furnace slag and steel slag (table 

1). Air-cooled blast furnace slag sales totaled about 8.1 Mt in 

2004, up by about 11% from the amount sold in 2003. Steel 

furnace slag sales rose by about 2% in 2004 to 9.0 Mt. For 

all years, the sales data for air-cooled and steel furnace slags 

largely exclude material returned to the furnaces (and likewise 

exclude the weight of free metal recovered from the slag and 

returned to the furnace); data on these returns are substantially 

unavailable. Air-cooled and steel furnace slags have a similar 

set of uses—mostly for various applications as aggregates 

(table 3). Because of potential expansion problems, steel slags 

find less use for applications requiring maintenance of a fixed 

volume (for example, concrete). Steel slags that contain a lot of 

free lime can have application as a soil conditioner. Most slags 

can be used as raw material for cement (clinker) manufacture 

(the slag contributes aluminum, calcium, iron, and silicon 

oxides) but steel slags have proven to be especially suitable for 

this use. Although the sales price data for air-cooled and steel 

slags contain a large component of estimates, it appears that 

the average selling price of air-cooled slag was more or less 

stagnant in 2004, whereas the prices for steel slag may have 

risen slightly (table 2). Typically, the major factors affecting the 

sales volumes and prices of these slags include local competition 

from natural aggregates, the overall level of construction activity 

(particularly that for roads), and the existence of some longterm supply contracts. Because of generally low unit sales 

values, slags for aggregate applications generally cannot sustain 

long-distance transportation. Slag converted to mineral wool 

is mainly used for thermal insulation. Although the specific 

sales data are withheld, pelletized slag is primarily used for 

lightweight concrete aggregate. When finely ground, pelletized 

slag can be used as a supplementary cementitious material 

similar to GGBFS.

In terms of value (in contrast to tonnages), the slag market 

in the United States is dominated by sales of granulated blast 

furnace slag, particularly GGBFS. In 2004, granulated slag 

accounted for almost 82% of the value of total blast furnace 

slag sales and 73% of total ferrous slag sales; both of these 

percentages were slightly higher than in 2003 (table 1). The 

tonnage of granulated slag sold in 2004 increased about 14% to 

4.1 Mt. Although not revealed in table 1, about 3.6 Mt of this 

was GGBFS, and the rest was unground material. The value 

dominance of granulated slag reflects its high unit value relative 

to the other slag types (table 2), and this, in turn, reflects the 

ready market for GGBFS as a partial substitute for portland 

cement in ready-mixed concrete or mixed with portland cement 

to make finished blended cement. In both applications, the 

hydration of the portland cement releases the lime needed to 

activate the GGBFS. Concrete that contains a proportion of 

GGBFS generally develops strength more slowly than concretes 

containing only portland cement but can have similar or even 

superior long-term strength, releases less heat during hydration, 

has reduced permeability, and shows improved resistance to 

chemical attack. A small fraction of the (unground) granulated 

slag on the market has been sourced from old slag piles and 

lacks cementitious properties as a result of weathering; this 

material can still be used as a fine grain aggregate for concrete, 

but sells for much lower prices than those indicated in table 2 

for the cementitious material.

The USGS slag survey does not distinguish between 

granulated slag sold directly to cement companies and that 

sold directly to concrete companies, but the 2004 USGS 

cement survey indicated that the cement producers themselves 

consumed only about 8% of the total granulated slag sales. 

Sales of GGBFS under the designation “slag cement” are 

promoted by the Slag Cement Association (SCA), whose 

members accounted for most of the U.S. output of this ground 

material. The SCA Web site reported sales of 3.46 Mt of 

GGBFS in 2004, which is in close agreement with the USGS 
Slag—Iron and Steel—2004 69.

data (Slag Cement Association, written commun., June 2, 2005).

Imports of ferrous slags (excluding iron scales) totaled about 

1.0 Mt in 2004, down by about 10% from levels in 2003. The 

imports continued to be dominated by granulated blast furnace 

slag. In 2004, imports of granulated slag (mostly as unground 

material) totaled 0.76 Mt compared with 0.75 Mt in 2003. For 

2004, the average unit value (customs value) for imported 

granulated slag was $36.93 per metric ton; it averaged $34.93 

per ton in 2003. By comparison, the cost, insurance, and freight 

value was $49.89 per metric ton in 2004 and $44.54 per ton 

in 2003; the differences relative to the customs values largely 

reflect the shipping charges, which rose substantially in 2004. 

Of the nine countries that supplied granulated slag in 2004, the 

leading sources were France (37%), Italy (25%), and Canada 

(18%).

Outlook

Granulators are currently installed at only five locations in the 

United States, and despite the high prices realized for GGBFS, 

it is unclear if granulation capacity will be increased. This is 

because of the high costs to install granulators, the costs of 

constructing an associated grinding plant, and by the precarious 

health of the integrated iron and steel plants. Together with 

the output from existing import-based grinding plants, it is 

likely that additional demand for GGBFS will be met by 

adding import-based grinding capacity; the new grinding plant 

in Florida is an example of this trend. Growth in the market 

for slag as an aggregate will depend on overall construction 

spending levels and on the success of industry efforts to promote 

slag as a sustainable construction material.

Reference Cited

American Iron and Steel Institute, 2004, Annual statistical report: Washington, 

DC, American Iron and Steel Institute, 138 p.

General Sources of Information

U.S. Geological Survey Publication

Iron and Steel Slag. Ch. in Mineral Commodities Summaries, 

annual.

Other

National Slag Association.

Portland Cement Association.

Slag Cement Association.

TABLE 1

IRON AND STEEL SLAG SOLD OR USED IN THE UNITED STATES

(Million metric tons and million dollars)

2003 2004

Blast furnace slag1 Steel Total iron Blast furnace slag1 Steel Total iron 

Air-cooled Granulated Total2 furnace slag and steel slag

2 Air-cooled Granulated Total2 furnace slag and steel slag2

Quantity

3 7.3 3.6 10.9 8.8 19.7 8.1 4.1 12.2 9.0 21.2

Valuee, 4 49 212 261 35 296 53 236 289 39 328 e

Estimated.

1

Excludes expanded (pelletized) slag to protect company proprietary data. The quantity is very small (less than 0.1 unit). 

2

Data may not add to totals shown because of independent rounding.

3

Quantities are rounded to reflect inclusion of some estimated data and to reflect inherent accuracy limitations of reported data. 

4

Values are rounded because of the inclusion of a large estimated component.

TABLE 2

SELLING PRICES FOR IRON AND STEEL SLAG IN THE UNITED STATES1

(Dollars per metric ton)

2003 2004

Slag type Range Average Range Average

Blast furnace slag:

Air-cooled 3.11-17.25 6.71 1.54-17.35 6.58

Granulated

2 16.53-78.20 62.52 22.05-71.65 61.49

Steel slag 0.73-11.02 3.95 0.22-7.89 4.32 1

Underlying data contain a large component of estimates.

2

Range shown is for material reported for use as a cementious additive in cement or

concrete manufacture. Material at the low end of the range is sold in unground form.
69. u.s. geologicAl survey minerals yearbook—2004

TABLE 3

SALES OF FERROUS SLAGS IN THE UNITED STATES , BY USE1

(Percentage of total tons sold)

2003 2004

Blast furnace slag2 Steel Blast furnace slag2 Steel

Use Air-cooled Granulated slag3 Air-cooled Granulated slag3

Ready-mixed concrete 9.3 -- -- 20.4 -- --

Concrete products 6.4 -- -- 3.5 -- --

Asphaltic concrete 20.6 -- 17.0 20.4 -- 12.9

Road bases and surfaces 34.7 -- 46.4 32.3 -- 63.5

Fill 3.1 -- 11.1 4.9 -- 9.6

Cementitious material -- 92.8 -- -- 91.1 --

Clinker raw material 5.7 -- 5.4 1.9 -- 5.5

Miscellaneous4 4.0 -- 2.5 4.2 -- 2.9

Other or unspecified 16.2 7.2 17.6 12.4 8.9 5.6

-- Zero.

1

Data contain a large component of estimates and are reliable to no more than two significant digits.

2

Excludes expanded or pelletized slag; this material is generally sold as a lightweight aggregate.

3

Steel slag use is based on the 89% of total tons sold in 2003 and the 77% of total tons in 2004 (table

1) for which usage data were provided.

4

Reported as used for railroad ballast, roofing, mineral wool, or soil conditioner.

TABLE 4

PROCESSORS OF IRON AND STEEL SLAG IN THE UNITED STATES IN 2004

Slag and furnace types1

Blast furnace slag Steel furnace slag

Slag processing company Plant location Steel company serviced

2, 3 AC GG Exp BOF OHF EAF

AMSI Holsopple, PA North American Höganäs, Inc. X

Barfield Enterprises, Inc. La Place, LA Bayou Steel Corp. X

Do. Lone Star, TX Lone Star Steel Corp. X

Beaver Valley Slag Aliquippa, PA Old slag pile site X X

Do. (Thor Mill Services) Roanoke, VA Roanoke Electric Steel, Inc. X

Blackheart Slag Co. Muscatine (Montpelier), IA IPSCO Steel, Inc. X

Border Steel, Inc. El Paso, TX Border Steel, Inc. X

Buffalo Crushed Stone, Inc. Woodlawn, NY Old slag pile site X

Buzzi Unicem USA, Inc. New Orleans, LA Various foreign X

Civil & Marine, Inc. Cape Canaveral, FL do. X

Edward C. Levy Co. Decatur (Trinity), AL Nucor Steel Corp. X

Do. Butler, IN Steel Dynamics Inc. X

Do. Columbia City, IN do. X

Do. Crawfordsville, IN Nucor Steel Corp. X

Do. Detroit, MI Severstal North America, Inc. X X

Do. do. U.S. Steel Corp. X X

Do. Canton, OH The Timken Co. X

Do. Delta, OH North Star-Bluescope Steel Inc. X

Do. Huger, SC Nucor Steel Corp. X

Essroc Corp. Middlebranch, OH Miscellaneous domestic and foreign X

Florida Rock Industries, Inc. Tampa, FL Various foreign X

Fritz Enterprises, Inc. Fairfield, AL U.S. Steel LLC X X

Gerdau Ameristeel Corp. Jacksonville, FL Gerdau Ameristeel Corp. X

Do. Charlotte, NC4 do. X

Glens Falls-Lehigh Cement Co. Cementon, NY Various foreign X

Holcim (US) Inc. Birmingham (Fairfield), AL U.S. Steel LLC X

Do. Gary, IN do. X

Do. Weirton, WV Weirton Steel Corp. X

See footnotes at end of table
Slag—Iron and Steel—2004 69.

TABLE 4—Continued

PROCESSORS OF IRON AND STEEL SLAG IN THE UNITED STATES IN 2004

Slag and furnace types1

Blast furnace slag Steel furnace slag

Slag processing company Plant location Steel company serviced

2, 3 AC GG Exp BOF OHF EAF

Lafarge North America Inc. Chicago, IL Ispat Inland Steel, Inc. X

Do. Joppa, IL do. X

Do. East Chicago, IN do. X

Do. Sparrows Point, MD International Steel Group Inc. X

Do. Cleveland (Cuyahoga Co.), OH5 do. X

Do. Lordstown, OH Old slag pile site X

Do. McDonald, OH Youngstown Sheet and Tube Co. X

Do. Salt Springs (Youngstown), OH do. X

Do. Warren, OH WCI Steel Inc. X

Do. West Mifflin, PA U.S. Steel LLC (ET Works) X

Do. West Mifflin (Brown Reserve), PA Old slag pile site X

Do. Whitehall, PA Various foreign X

Do. Seattle, WA do. X

Do. Weirton, WV Weirton Steel Corp. X

Lehigh Cement Evansville, PA Various foreign X

Levy Co., Inc., The Burns Harbor, IN International Steel Group Inc. X X

Do. East Chicago, IN do. X

Do. Gary, IN U.S. Steel LLC X X

Mountain Enterprises, Inc. Ashland, KY5 AK Steel Corp. X

MultiServ Birmingham, AL Structural Metals Corp. X

Do. Tuscaloosa, AL Nucor Steel Corp. X

Do. Blytheville, AR do. X

Do. Blytheville (Armorel), AR Nucor-Yamato Steel Co. X

Do. Pueblo, CO Rocky Mountain Steel Mills X

Do. Wilton (Muscatine), IA IPSCO Steel, Inc. X

Do. East Chicago, IN Ispat Inland Steel, Inc. X

Do. Indiana Harbor, IN International Steel Group Inc. X

Do. Ghent, KY Gallatin Steel Co. X

Do. Sparrows Point, MD International Steel Group Inc. X X

Do. Ahoskie (Cofield), NC Nucor Steel Corp. X

Do. Canton, OH Republic Engineered Products LLC X

Do. Mansfield, OH AK Steel Corp. X

Do. Warren, OH WCI Steel Inc. X

Do. Braddock (Mon Valley), PA U.S. Steel/Republic Technologies X

Do. Butler, PA AK Steel Corp. X

Do. Coatesville. PA International Steel Group Inc. X

Do. Koppel, PA Koppel Steel Co. (NS Group, Inc.) X

Do. Steelton, PA International Steel Group Inc. X

Do. Midlothian, TX TXI Chaparral Steel Co. X

Do. Geneva (Provo), UT Geneva Steel Holdings Corp.

6 X X

Do. Seattle, WA Nucor Steel Corp. X

Rinker Materials Corp. Miami, FL Various foreign X

St. Lawrence Cement, Inc. Camden, NJ do. X

St. Marys Cement, Inc. Detroit, MI do. X

Stein, Inc. Sterling, IL Sterling Steel, Inc. X

Do. Ashland, KY5 AK Steel Corp. X X

Do. Cleveland, OH5 International Steel Group Inc. X X

Do. Loraine, OH Republic Engineered Products LLC X X

Titan Florida, Inc. Medley, FL Various foreign X

Tube City IMS Corp.

7 Birmingham, AL Nucor Steel Corp. X

Do. Newport, AR8 Arkansas Steel Assoc. X

Do. Rancho Cucamonga, CA TAMCO Steel X

Do. Portage, IN Beta Steel Corp. X

Do. Norfolk, NE Nucor Steel Corp. X

Do. Perth Amboy, NJ

9 Gerdau Ameristeel Corp. X

Do. Sayreville, NJ9 do. X

Do. Middletown, OH AK Steel Corp. X X

Do. Mingo Junction, OH Wheeling Pittsburgh Steel Corp. X X

Do. Youngstown, OH V&M Star (North Star, Inc.) X

Do. Sand Springs, OK Sheffield Steel Corp. X

See footnotes at end of table
69. u.s. geologicAl survey minerals yearbook—2004

TABLE 4—Continued

PROCESSORS OF IRON AND STEEL SLAG IN THE UNITED STATES IN 2004

Slag and furnace types1

Blast furnace slag Steel furnace slag

Slag processing company Plant location Steel company serviced

2, 3 AC GG Exp BOF OHF EAF

Tube City IMS Corp.--Continued:7 Cayce, SC SMI/CMC Steel Group X

Do. Knoxville, TN Gerdau Ameristeel Corp. X

Do. Seguin, TX SMI/CMC Steel Group X

Do. Petersburg, VA TXI Chaparral Steel Co. X

Tube City-IMS, IMS Division

10 Axis, AL IPSCO Steel, Inc. X

Do. Fort Smith, AR Macsteel X

Do. Newport, AR8 Arkansas Steel Assoc. X

Do. Kingman, AZ North Star Steel Inc. X

Do. Claymont, DE CitiSteel USA, Inc. X

Do. Cartersville, GA Gerdau Ameristeel Corp. X

Do. Wilton (Muscatine), IA do. X

Do. Kankakee, IL Nucor Steel Corp. X

Do. Peoria, IL Keystone Steel & Wire Co. X

Do. Laplace, LA Bayou Steel Corp. X

Do. Jackson, MI Macsteel X

Do. Monroe, MI Macsteel (Quanex) X

Do. St. Paul, MN Gerdau Ameristeel Corp. X

Do. Jackson, MS Nucor Steel Corp. X

Do. Charlotte, NC4 Gerdau Ameristeel Corp. X

Do. Perth Amboy, NJ

9 do. X

Do. Sayreville, NJ9 do. X

Do. Auburn, NY Nucor Steel Corp. X

Do. Marion, OH Marion Steel Co. X

Do. McMinnville, OR Cascade Steel Rolling Mills, Inc. X

Do. Portland, OR Oregon Steel Mills Inc. X

Do. Bethlehem, PA Old slag pile site X X

Do. Bridgeville, PA Universal Stainless & Alloy Products Inc. X

Do. Midland, PA J&L Specialty Products, Inc. X

Do. Monroeville, PA Old slag pile site X

Do. New Castle, PA Ellwood Quality Steels Co. X

Do. Park Hill (Johnstown), PA Old slag pile site X

Do. Pricedale, PA do. X

Do. Reading, PA Carpenter Technology Corp. X

Do. Darlington, SC Nucor Steel Corp. X

Do. Georgetown, SC11 Georgetown Steel Corp. X

Do. Jackson, TN Gerdau Ameristeel Corp. X

Do. Beaumont, TX do. X

Do. Jewett, TX Nucor Steel Corp. X

Do. Longview, TX LeTourneau Steel Group X

Do. Plymouth, UT Nucor Steel Corp. X

Do. Saukville, WI Charter Steel X

Do. Weirton, WV Weirton Steel Corp. X 1

Blast furnace slag type abbreviations: AC, air-cooled; GG, granulated; Exp, expanded. Steel furnace slag types: BOF, basic oxygen furnace; OHF, open hearth 

furnace; EAF, electric arc furnace.

2

"Various foreign" refers to the fact that the facility imports unground granulated blast furnace slag and grinds it on site to make ground granulated blast furnace 

slag, commonly now referred to as "slag cement."

3

Currently operating iron and/or steel company. Company is not shown for old slag pile sites.

4

IMS processing contract was taken over by Gerdau Ameristeel in June 2004.

5

For the air-cooled slag, Stein was responsible for the cooling, but the processing and marketing was handled by Lafarge Corp. (Cleveland, OH) and Mountain 

Enterprises, Inc. (Ashland, KY), respectively.

6

The Geneva Steel plant shut down in 2002; slag processing is of small residual piles.

7

Formerly Olympic Mill Services, Inc. (OMS) and was renamed following the December 2004 merger of OMS' parent company, Tube City, LLC, with Olympic 

Mill Services, Inc.

8

Contract transferred from Tube City-IMs to Uniserve LLC in February 2004.

9

Contracts were transferred to OMS (became Tube City-IMS) in September 2004 (Perth Amboy), and December 2004 (Sayreville).

10Formerly International Mill Services, Inc. (IMS) and was renamed following the December 2004 merger of IMS with Tube City, LLC.

11Contract was transferred to Stein, Inc. in July 2004.