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   &lt;div style="font-family: 'Times New Roman',Times,serif"&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;&lt;b&gt;12. Share-Based Compensation&lt;/b&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;During the first six months of 2010, we granted share-based compensation to eligible participants
   under our Long-Term Incentive Plan. We recognize expense on all share-based grants over the service
   period, which is the shorter of the period until the employees&amp;#8217; retirement eligibility dates or the
   service period of the award for awards expected to vest. Expense is generally reduced for estimated
   forfeitures.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;STOCK OPTIONS
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;We granted stock options to purchase 1,006,012 shares of common stock during the first six
   months of 2010 with an exercise price equal to the closing price of our common stock on the date of
   the grants. The stock options generally become exercisable in four equal annual installments
   beginning one year from the date of grant, although they may become exercisable earlier in the
   event of death, disability, retirement or a change in control, except that 46,000 of the stock
   options were granted as special retention awards that generally will vest 100% after three years.
   The stock options generally expire 10&amp;#160;years from the date of grant, or earlier in the event of
   death, disability or retirement.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;We estimated the fair value of each stock option granted to be $5.92 on the date of grant
   using a Black-Scholes option valuation model that uses the assumptions noted below. We based
   expected volatility on a 50% weighting of peer volatilities and 50% weighting of implied
   volatilities. We did not consider historical volatility of our common stock price to be an
   appropriate measure of future volatility because of the impact that our Chapter&amp;#160;11 proceedings
   completed in 2006 had on our historical stock price. The risk-free rate was based on zero-coupon
   U.S. government issues at the time of grant. The expected term was developed using the simplified
   method, as permitted by the SEC because there is not sufficient historical stock option exercise
   experience available.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The assumptions used in the valuation were as follows: expected volatility 46.90%, risk-free
   rate 2.97%, expected term (in years) 6.25 and expected dividends 0.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;RESTRICTED STOCK UNITS
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;We granted RSUs with respect to 697,249 shares of common stock during the first six months of
   2010. RSUs generally vest in four equal annual installments beginning one year from the date of
   grant, except that 21,356 of these RSUs were granted as special awards that generally will vest
   100% after three to five years. RSUs may vest earlier in the case of death, disability, retirement
   or a change in control. Each RSU is settled in a share of our common stock after the vesting
   period. The fair value of each RSU granted is equal to the closing price of our common stock on the
   date of grants. Virtually all RSUs granted in the first six months of 2010 had a fair value of
   $11.98.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;PERFORMANCE SHARES
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;We granted 332,716 performance shares during the first six months of 2010. The performance
   shares generally vest after a three-year period based on our total stockholder return relative to
   the performance of the Dow Jones U.S. Construction and Materials Index, with adjustments to that
   index in certain circumstances, for the three-year period. The number of performance shares earned
   will vary from 0 to 200% of the number of performance shares awarded depending on that relative
   performance. Vesting will be prorated based on the number of full months employed during the
   performance period in the case of death, disability, retirement or a change-in-control, and
   pro-rated awards earned will be paid at the end of the three-year period. Each performance share
   earned will be settled in a share of our common stock.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;We estimated the fair value of each performance share granted to be $15.59 on the date of
   grant using a Monte Carlo simulation that uses the assumptions noted below. Expected volatility is
   based on implied volatility of our
   traded options and the daily historical volatilities of our peer
   group. The risk-free rate was based on zero-coupon
   U.S. government issues at the time of grant. The expected term represents the period from the grant
   date to the end of the three-year performance period.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The assumptions used in the valuation were as follows: expected volatility 73.34%, risk-free
   rate 1.24%, expected term (in years) 2.89 and expected dividends 0.
   &lt;/div&gt;
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      <ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 123R
 -Paragraph 64, 65, A240

Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher AICPA
 -Name Statement of Position (SOP)
 -Number 93-6
 -Paragraph 53

Reference 3: http://www.xbrl.org/2003/role/presentationRef
 -Publisher SEC
 -Name Staff Accounting Bulletin (SAB)
 -Number Topic 14

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