Item 1B. UNRESOLVED STAFF COMMENTS

There are no unresolved written comments that were received from the staff of the SEC one hundred and eighty (180) days or more before the end of our fiscal year relating to our periodic or current reports under the Exchange Act.

ITEM 2 - PROPERTIES

Building Materials Business

As of December 31, 2018, the Company processed or shipped aggregates from more than 300 quarries, underground mines, and distribution yards in 26 states, Canada, and the Bahamas, of which 124 are located on land owned by the Company free of major encumbrances, 61 are on land owned in part and leased in part, 110 are on leased land, and 10 are on facilities neither owned nor leased, where raw materials are removed under an agreement. The Company’s aggregates reserves, on the average, exceed 75 years based on normalized levels of production, and approximate 100 years at current production rates. However, certain locations may be subject to more limited reserves and may not be able to expand. In addition, as of December 31, 2018, the Company processed and shipped ready mixed concrete and/or asphalt products from 149 properties in five states, of which 126 are located on land owned by the Company free of major encumbrances, one is on land owned in part and leased in part, and 22 are on leased land.

The Company uses various drilling methods, depending on the type of aggregate, to estimate aggregates reserves that are economically mineable. The extent of drilling varies and depends on whether the location is a potential new site (greensite), an existing location, or a potential acquisition. More extensive drilling is performed for potential greensites and acquisitions, and in rare cases, the Company may rely on existing geological data or results of prior drilling by third parties. Subsequent to drilling, selected core samples are tested for soundness, abrasion resistance, and other physical properties relevant to the aggregates industry. If the reserves meet the Company’s standards and are economically mineable, then they are either leased or purchased.

The Company estimates proven and probable reserves based on the results of drilling. Proven reserves are reserves of deposits designated using closely spaced drill data, and based on that data the reserves are believed to be relatively homogenous. Proven reserves have a certainty of 85% to 90%. Probable reserves are reserves that are inferred utilizing fewer drill holes and/or assumptions about the economically mineable reserves based on local geology or drill results from adjacent properties. The degree of certainty for probable reserves is 70% to 75%. In determining the amount of reserves, the Company’s policy is to not include calculations that exceed certain depths, so for deposits, such as granite, that typically continue to depths well below the ground, there may be additional deposits that are not included in the reserve calculations. The Company also deducts reserves not available due to property boundaries, set-backs, and plant configurations, as deemed appropriate when estimating reserves. The Company uses the same methods of analysis to evaluate and estimate the amount of its aggregates reserves used in the cement manufacturing process for its cement product line as

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Part I ◆ Item 2 - Properties

it does for its aggregates product line. For additional information on the Company’s assessment of reserves, see “Management’s Discussion and Analysis of Financial Condition and Results of Operations – Other Financial Information – Critical Accounting Policies and Estimates- Property, Plant and Equipment” included in the 2018 Annual Report filed as Exhibit 13.01 to this Form 10-K for a discussion of reserves evaluation by the Company.

Set forth in the tables below are the Company’s estimates of reserves of recoverable aggregates (hard rock and sand and gravel) of suitable quality for economic extraction, shown on a state-by-state basis, and the Company’s total annual production for the last three years, along with the Company’s estimate of years of production available, shown on a segment-by-segment basis. The number of producing quarries shown on the table includes underground mines. The Company’s reserve estimates for the last two years are shown for comparison purposes on a state-by-state basis. The changes in reserve estimates at a particular state level from year to year reflect the tonnages of reserves on locations that have been opened or closed during the year, whether by acquisition, disposition, or otherwise; production and sales in the normal course of business; additional reserve estimates or refinements of the Company’s existing reserve estimates; opening of additional reserves at existing locations; the depletion of reserves at existing locations; and other factors. The Company evaluates its reserve estimates primarily on a Company-wide, or segment-by-segment basis, and does not believe comparisons of changes in reserve estimates on a state-by-state basis from year to year are particularly meaningful. The Company’s estimate of reserves shown in the tables below include reserves used in the Company’s cement product line and Magnesia Specialties business.

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