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USD ($)

USD ($) / shares

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   &lt;!-- Begin Block Tagged Note 14 - us-gaap:CommitmentsAndContingenciesDisclosureTextBlock--&gt;
   &lt;div style="margin-left: 0%"&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;table width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt; font-family: Arial, Helvetica; color: #000000; background: transparent; text-align: left"&gt;
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       &lt;td width="8%"&gt;&lt;/td&gt;
       &lt;td width="92%"&gt;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="top"&gt;
       &lt;td&gt;
       &lt;b&gt;&lt;font style="font-family: 'Times New Roman', Times"&gt;NOTE&amp;#160;14.&amp;#160;&lt;/font&gt;&lt;/b&gt;
   &lt;/td&gt;
       &lt;td&gt;
       &lt;b&gt;&lt;font style="font-family: 'Times New Roman', Times"&gt;COMMITMENTS
       AND CONTINGENCIES&lt;/font&gt;&lt;/b&gt;
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;/table&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 1%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       We &lt;font style="white-space: nowrap"&gt;and/or&lt;/font&gt;
       our subsidiaries are party to a number of claims, lawsuits and
       pending actions, most of which are routine and all of which are
       incidental to our business. We assess the likelihood of
       potential losses on an ongoing basis and when losses are
       considered probable and reasonably estimable, record as a loss
       an estimate of the outcome. If we can only estimate the range of
       a possible loss, an amount representing the low end of the range
       of possible outcomes is recorded. The final consequences of
       these proceedings are not presently determinable with certainty.
   &lt;/div&gt;
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   &lt;b&gt;
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   &lt;/font&gt;
   &lt;/b&gt;
   &lt;/div&gt;
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   &lt;div style="margin-top: 12pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; font-size: 10pt; font-family: Arial, Helvetica; color: #000000; background: transparent"&gt;
       &lt;b&gt;&lt;font style="font-family: 'Times New Roman', Times"&gt;Environmental
       Matters&lt;/font&gt;&lt;/b&gt;
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 1%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       Our operations are subject to environmental regulatory laws and
       environmental remediation laws. Although our operations are
       occasionally subject to proceedings and orders pertaining to
       emissions into the environment and other environmental
       violations, which may result in fines, penalties, damages or
       other sanctions, we believe that we are in substantial
       compliance with existing environmental laws and regulations.
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 1%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       We may be identified, along with other entities, as being among
       parties potentially responsible for contribution to costs
       associated with the correction and remediation of environmental
       conditions at disposal sites subject to federal
       &lt;font style="white-space: nowrap"&gt;and/or&lt;/font&gt;
       analogous state laws. In certain instances, we may be exposed to
       joint and several liabilities for remedial action or damages.
       Our liability in connection with such environmental claims will
       depend on many factors, including our volumetric share of waste,
       the total cost of remediation, and the financial viability of
       other companies that also sent waste to a given site and, in the
       case of divested operations, its contractual arrangement with
       the purchaser of such operations.
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 1%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       The potential costs related to the matters described below and
       the possible impact on future operations are uncertain due in
       part to the complexity of governmental laws and regulations and
       their interpretations, the varying costs and effectiveness of
       cleanup technologies, the uncertain level of insurance or other
       types of recovery and the questionable level of our
       responsibility. Although the ultimate outcome and expense of any
       litigation, including environmental remediation, is uncertain,
       we believe that the following proceedings will not have a
       material adverse effect on our condensed consolidated financial
       position or results of operations.
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 1%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       &lt;i&gt;Wallingford Matter.&lt;/i&gt;&amp;#160;In 2010, compliance stack
       testing indicated that one of the three combustion units at the
       Wallingford energy-from-waste facility had exceeded the permit
       limit for dioxin/furan emissions. We promptly shut down the
       affected combustion unit and self-reported the test results to
       the Connecticut Department of Environmental Protection
       (&amp;#8220;CTDEP&amp;#8221;). On August&amp;#160;18, 2010, the Connecticut
       Office of the Attorney General (&amp;#8220;AG&amp;#8221;), on behalf of
       the CTDEP, commenced an enforcement action in Connecticut
       Superior Court (Hartford) with respect to the results of the
       compliance stack testing. We are working cooperatively with the
       CTDEP and AG to reach agreement on a restart and test program to
       demonstrate that the affected combustion unit has been returned
       to compliance. It is not possible at this time to predict the
       outcome or to estimate our ultimate liability in the matter;
       however, we believe this proceeding and related suspension in
       operation will not have a material adverse effect on our
       condensed consolidated financial position or results of
       operations.
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 1%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       &lt;i&gt;Lower Passaic River Matter.&lt;/i&gt;&amp;#160;In August 2004, the
       United States Environmental Protection Agency (&amp;#8220;EPA&amp;#8221;)
       notified Covanta Essex Company (&amp;#8220;Essex&amp;#8221;) that it was a
       potentially responsible party (&amp;#8220;PRP&amp;#8221;) for Superfund
       response actions in the Lower Passaic River Study Area, referred
       to as &amp;#8220;LPRSA,&amp;#8221; a 17&amp;#160;mile stretch of river in
       northern New Jersey. Essex is one of 71 PRPs named thus far that
       have joined the LPRSA PRP group, which is undertaking a Remedial
       Investigation/Feasibility Study (&amp;#8220;Study&amp;#8221;) of the LPRSA
       under EPA oversight. Essex&amp;#8217;s share of the Study costs to
       date are not material to its financial position and results of
       operations; however, the Study costs are exclusive of any LPRSA
       remedial costs or natural resource damages that may ultimately
       be assessed against PRPs. In February 2009, Essex and over 300
       other PRPs were named as third-party defendants in a suit
       brought by the State of New Jersey Department of Environmental
       Protection (&amp;#8220;NJDEP&amp;#8221;) in New Jersey Superior Court of
       Essex County against Occidental Chemical Corporation and certain
       related entities (&amp;#8220;Occidental&amp;#8221;) with respect to
       alleged contamination of the LPRSA by Occidental. The Occidental
       third-party complaint seeks contribution with respect to any
       award to NJDEP of damages against Occidental in the matter.
       Considering the history of industrial and other discharges into
       the LPRSA from other sources, including named PRPs, Essex
       believes any releases to the LPRSA from its facility to be de
       minimis; however, it is not possible at this time to predict
       that outcome or to estimate Essex&amp;#8217;s ultimate liability in
       the matter, including for LPRSA remedial costs
       &lt;font style="white-space: nowrap"&gt;and/or&lt;/font&gt;
       natural resource damages
       &lt;font style="white-space: nowrap"&gt;and/or&lt;/font&gt;
       contribution claims made by Occidental
       &lt;font style="white-space: nowrap"&gt;and/or&lt;/font&gt; other
       PRPs.
   &lt;/div&gt;
   &lt;!-- XBRL Pagebreak Begin --&gt;
   &lt;/div&gt;
   &lt;!-- END PAGE WIDTH --&gt;
   &lt;!-- PAGEBREAK --&gt;
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   &lt;!-- BEGIN PAGE WIDTH --&gt;
   &lt;div align="center" style="margin-left: 0%; margin-right: 0%; font-size: 10pt; font-family: Arial, Helvetica; color: #000000; background: transparent"&gt;
   &lt;b&gt;
   &lt;font style="font-family: 'Times New Roman', Times"&gt;
   &lt;/font&gt;
   &lt;/b&gt;
   &lt;/div&gt;
   &lt;!-- XBRL Pagebreak End --&gt;
   &lt;div style="margin-top: 12pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; font-size: 10pt; font-family: Arial, Helvetica; color: #000000; background: transparent"&gt;
       &lt;b&gt;&lt;font style="font-family: 'Times New Roman', Times"&gt;Other
       Matters&lt;/font&gt;&lt;/b&gt;
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 1%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       Other commitments as of March&amp;#160;31, 2011 were as follows (in
       thousands):
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;table border="0" width="100%" align="center" cellpadding="0" cellspacing="0" style="font-size: 9pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent; text-align: left"&gt;
   &lt;!-- Table Width Row BEGIN --&gt;
   &lt;tr style="font-size: 1pt" valign="bottom"&gt;
       &lt;td width="63%"&gt;&amp;#160;&lt;/td&gt;&lt;!-- colindex=01 type=maindata --&gt;
       &lt;td width="2%"&gt;&amp;#160;&lt;/td&gt;&lt;!-- colindex=02 type=gutter --&gt;
       &lt;td width="1%" align="right"&gt;&amp;#160;&lt;/td&gt;&lt;!-- colindex=02 type=lead --&gt;
       &lt;td width="9%" align="right"&gt;&amp;#160;&lt;/td&gt;&lt;!-- colindex=02 type=body --&gt;
       &lt;td width="1%" align="left"&gt;&amp;#160;&lt;/td&gt;&lt;!-- colindex=02 type=hang1 --&gt;
       &lt;td width="2%"&gt;&amp;#160;&lt;/td&gt;&lt;!-- colindex=03 type=gutter --&gt;
       &lt;td width="1%" align="right"&gt;&amp;#160;&lt;/td&gt;&lt;!-- colindex=03 type=lead --&gt;
       &lt;td width="7%" align="right"&gt;&amp;#160;&lt;/td&gt;&lt;!-- colindex=03 type=body --&gt;
       &lt;td width="1%" align="left"&gt;&amp;#160;&lt;/td&gt;&lt;!-- colindex=03 type=hang1 --&gt;
       &lt;td width="2%"&gt;&amp;#160;&lt;/td&gt;&lt;!-- colindex=04 type=gutter --&gt;
       &lt;td width="1%" align="right"&gt;&amp;#160;&lt;/td&gt;&lt;!-- colindex=04 type=lead --&gt;
       &lt;td width="9%" align="right"&gt;&amp;#160;&lt;/td&gt;&lt;!-- colindex=04 type=body --&gt;
       &lt;td width="1%" align="left"&gt;&amp;#160;&lt;/td&gt;&lt;!-- colindex=04 type=hang1 --&gt;
   &lt;/tr&gt;
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   &lt;!-- TableOutputHead --&gt;
   &lt;tr style="font-size: 7pt" valign="bottom" align="center"&gt;
   &lt;td nowrap="nowrap" align="center" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td colspan="10" align="center" valign="bottom" style="border-bottom: 1px solid #000000"&gt;
       &lt;b&gt;Commitments Expiring by Period&lt;/b&gt;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr style="font-size: 7pt" valign="bottom" align="center"&gt;
   &lt;td nowrap="nowrap" align="center" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td colspan="2" nowrap="nowrap" align="center" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td colspan="2" nowrap="nowrap" align="center" valign="bottom"&gt;
       &lt;b&gt;Less Than&lt;br /&gt;
       &lt;/b&gt;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td colspan="2" nowrap="nowrap" align="center" valign="bottom"&gt;
       &lt;b&gt;More Than&lt;br /&gt;
       &lt;/b&gt;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr style="font-size: 7pt" valign="bottom" align="center"&gt;
   &lt;td nowrap="nowrap" align="center" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td colspan="2" nowrap="nowrap" align="center" valign="bottom" style="border-bottom: 1px solid #000000"&gt;
       &lt;b&gt;Total&lt;/b&gt;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td colspan="2" nowrap="nowrap" align="center" valign="bottom" style="border-bottom: 1px solid #000000"&gt;
       &lt;b&gt;One Year&lt;/b&gt;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td colspan="2" nowrap="nowrap" align="center" valign="bottom" style="border-bottom: 1px solid #000000"&gt;
       &lt;b&gt;One Year&lt;/b&gt;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr style="line-height: 3pt; font-size: 1pt"&gt;
   &lt;td&gt;&amp;#160;
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;!-- TableOutputBody --&gt;
   &lt;tr valign="bottom" style="background: #cceeff"&gt;
   &lt;td align="left" valign="bottom"&gt;
   &lt;div style="text-indent: -9pt; margin-left: 9pt"&gt;
       Letters of credit
   &lt;/div&gt;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
       $
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="right" valign="bottom"&gt;
       &amp;#160;286,239
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
       $
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="right" valign="bottom"&gt;
       &amp;#160;8,270
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
       $
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="right" valign="bottom"&gt;
       &amp;#160;277,969
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom"&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
   &lt;div style="text-indent: -9pt; margin-left: 9pt"&gt;
       Surety bonds
   &lt;/div&gt;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="right" valign="bottom"&gt;
       85,889
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="right" valign="bottom"&gt;
       &amp;#8212;
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="right" valign="bottom"&gt;
       85,889
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom" style="font-size: 1pt"&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td style="border-top: 1px solid #000000"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td style="border-top: 1px solid #000000"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td style="border-top: 1px solid #000000"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td style="border-top: 1px solid #000000"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td style="border-top: 1px solid #000000"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td style="border-top: 1px solid #000000"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom" style="background: #cceeff"&gt;
   &lt;td align="left" valign="bottom"&gt;
   &lt;div style="text-indent: -9pt; margin-left: 9pt"&gt;
       Total other commitments&amp;#160;&amp;#8212; net
   &lt;/div&gt;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
       $
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="right" valign="bottom"&gt;
       372,128
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
       $
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="right" valign="bottom"&gt;
       8,270
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
       $
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="right" valign="bottom"&gt;
       363,858
   &lt;/td&gt;
   &lt;td nowrap="nowrap" align="left" valign="bottom"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom" style="font-size: 1pt"&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td style="border-top: 3px double #000000"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td style="border-top: 3px double #000000"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td style="border-top: 3px double #000000"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td style="border-top: 3px double #000000"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td style="border-top: 3px double #000000"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td style="border-top: 3px double #000000"&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;td&gt;
   &amp;#160;
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;/table&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 0%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 1%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       The letters of credit were issued under various credit
       facilities (primarily the Funded L/C Facility) to secure our
       performance under various contractual undertakings related to
       our domestic and international projects or to secure obligations
       under our insurance program. Each letter of credit relating to a
       project is required to be maintained in effect for the period
       specified in related project contracts, and generally may be
       drawn if it is not renewed prior to expiration of that period.
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 1%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       We believe that we will be able to fully perform under our
       contracts to which these existing letters of credit relate, and
       that it is unlikely that letters of credit would be drawn
       because of a default of our performance obligations. If any of
       these letters of credit were to be drawn by the beneficiary, the
       amount drawn would be immediately repayable by us to the issuing
       bank. If we do not immediately repay such amounts drawn under
       these letters of credit, unreimbursed amounts would be treated
       under the Credit Facilities as additional term loans in the case
       of letters of credit issued under the Funded L/C Facility, or as
       revolving loans in the case of letters of credit issued under
       the Revolving Credit Facility.
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 1%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       The surety bonds listed on the table above relate primarily to
       performance obligations ($74.8&amp;#160;million) and support for
       closure obligations of various energy projects when such
       projects cease operating ($11.1&amp;#160;million). Were these bonds
       to be drawn upon, we would have a contractual obligation to
       indemnify the surety company.
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 1%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       We have certain contingent obligations related to the
       7.25%&amp;#160;Notes and the 3.25%&amp;#160;Notes. These arise as
       follows:
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;table width="100%" border="0" cellpadding="0" cellspacing="0" style="text-align: left"&gt;
   &lt;tr&gt;
       &lt;td width="4%"&gt;&lt;/td&gt;
       &lt;td width="2%"&gt;&lt;/td&gt;
       &lt;td width="94%"&gt;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="top" style="font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;    &amp;#8226;&amp;#160;
   &lt;/td&gt;
       &lt;td align="left"&gt;
       holders may require us to repurchase their 7.25%&amp;#160;Notes and
       their 3.25%&amp;#160;Notes if a fundamental change occurs;&amp;#160;and
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="top" style="font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;    &amp;#8226;&amp;#160;
   &lt;/td&gt;
       &lt;td align="left"&gt;
       holders may exercise their conversion rights upon the occurrence
       of certain events, which would require us to pay the conversion
       settlement amount in cash.
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;/table&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 1%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       We have certain contingent obligations related to the
       Debentures. These arise as follows:
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;table width="100%" border="0" cellpadding="0" cellspacing="0" style="text-align: left"&gt;
   &lt;tr&gt;
       &lt;td width="4%"&gt;&lt;/td&gt;
       &lt;td width="2%"&gt;&lt;/td&gt;
       &lt;td width="94%"&gt;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="top" style="font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;    &amp;#8226;&amp;#160;
   &lt;/td&gt;
       &lt;td align="left"&gt;
       holders may require us to repurchase their Debentures on
       February&amp;#160;1, 2012, February&amp;#160;1, 2017 and
       February&amp;#160;1, 2022;
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="top" style="font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;    &amp;#8226;&amp;#160;
   &lt;/td&gt;
       &lt;td align="left"&gt;
       holders may require us to repurchase their Debentures if a
       fundamental change occurs;&amp;#160;and
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="top" style="font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;    &amp;#8226;&amp;#160;
   &lt;/td&gt;
       &lt;td align="left"&gt;
       holders may exercise their conversion rights upon the occurrence
       of certain events, which would require us to pay the conversion
       settlement amount in cash
       &lt;font style="white-space: nowrap"&gt;and/or&lt;/font&gt; our
       common stock.
   &lt;/td&gt;
   &lt;/tr&gt;
   &lt;/table&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 1%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       For specific criteria related to contingent interest, conversion
       or redemption features of the Debentures, the 7.25%&amp;#160;Notes
       and the 3.25%&amp;#160;Notes, refer to Note&amp;#160;12 of the Notes to
       Consolidated Financial Statements in our
       &lt;font style="white-space: nowrap"&gt;Form&amp;#160;10-K.&lt;/font&gt;
   &lt;/div&gt;
   &lt;div style="margin-top: 6pt; font-size: 1pt"&gt;&amp;#160;
   &lt;/div&gt;
   &lt;div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 1%; font-size: 10pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"&gt;
       We have issued or are party to guarantees and related
       contractual support obligations undertaken pursuant to
       agreements to construct and operate waste and energy facilities.
       For some projects, such performance guarantees include
       obligations to repay certain financial obligations if the
       project revenues are insufficient to do so, or to obtain or
       guarantee financing for a project. With respect to our
       businesses, we have issued guarantees to municipal clients and
       other parties that our subsidiaries will perform in accordance
       with contractual terms, including, where required, the payment
       of damages or other obligations. Additionally, damages payable
       under such guarantees for our energy-from-waste facilities could
       expose us to recourse liability on project debt. If we must
       perform under one or more of such guarantees, our liability for
       damages upon contract termination would be reduced by funds held
       in trust and proceeds from sales of the facilities securing the
       project debt and is presently not estimable. Depending upon the
       circumstances giving rise to such damages, the contractual terms
       of the applicable contracts, and the contract
       counterparty&amp;#8217;s choice of remedy at the time a
   claim against a guarantee is made, the amounts owed pursuant to
       one or more of such guarantees could be greater than our
       then-available sources of funds. To date, we have not incurred
       material liabilities under such guarantees.
   &lt;/div&gt;
   &lt;/div&gt;
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 -Publisher FASB
 -Name FASB Interpretation (FIN)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 5
 -Paragraph 9, 10, 11, 12

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