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<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;border-bottom:solid 2.25pt;padding-bottom:1;'>&nbsp;</p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=5>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><B><font SIZE=5>UNITED STATES</font></B></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><B><font SIZE=5>SECURITIES AND EXCHANGE COMMISSION</font></B></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=2>Washington, D.C. 20549</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=3>___________</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=3>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><B><font SIZE=5>FORM 8-K</font></B></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=3>____________</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=3>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><B><font SIZE=2>CURRENT REPORT</font></B></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=2>PURSUANT TO SECTION 13 OR 15(d) OF THE</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><B><font SIZE=2>SECURITIES EXCHANGE ACT OF 1934</font></B></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=3>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=2>Date of Report (Date of earliest event reported) April 29, 2008</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=3>____________</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=3>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><B><font SIZE=5>BLACK HILLS CORPORATION</font></B></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=2>(Exact name of registrant as specified in its charter)</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=3>____________</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=3>&nbsp;</font></p>


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            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>South Dakota</font></b></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>(State or other jurisdiction of incorporation)</font></b></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>001-31303</font></b></p> </td>
        <td width="234" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td  colspan="2" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>46-0458824</font></b></p> </td> </tr>
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        <td width="162" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>(Commission&nbsp;File&nbsp;Number)</font></b></p> </td>
        <td width="234" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td  colspan="2" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>(IRS&nbsp;Employer&nbsp;Identification&nbsp;No.)</font></b></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td width="234" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td  colspan="2" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><b><font size=2>625 Ninth Street, PO Box 1400 </font></b></p>
<p style='margin-left:12.6pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><b><font size=2>Rapid City, South Dakota</font></b></p>
<p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><b><font size=2>(Address of principal executive offices)</font></b></p> </td>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>57709-1400</font></b></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>(Zip Code)</font></b></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>605.721.1700</font></b></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>(Registrant&#146;s telephone number, including area code)</font></b></p> </td> </tr>
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        <td width="162" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td  colspan="2" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td width="186" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>Not Applicable</font></b></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>(Former name or former address, if changed since last report)</font></b></p> </td> </tr>
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        <td width="162" ></td>

        <td width="234" ></td>

        <td width="12" ></td>

        <td width="186" ></td> </tr> </table>
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<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=3>____________</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt; text-indent:0.5in;text-align:left;'><font size=2>Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (</font><i><font size=2>see</font></i><font size=2> General Instruction A.2. below):</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>


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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)</font></p> </td> </tr></table>
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<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>


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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)</font></p> </td> </tr></table>
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<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>


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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))</font></p> </td> </tr></table>
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<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>


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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))</font></p> </td> </tr></table>
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<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;border-bottom:solid 2.25pt;padding-bottom:1;'><font size=5>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=2>1</font></p>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><b><font size=2>Item 1.01</font></b></p> </td>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><b><font size=2>Entry into a Material Definitive Agreement</font></b></p> </td> </tr></table>
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<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:justify;'><font size=2>On February 6, 2007, we entered into agreements with Aquila, Inc. (&#147;Aquila&#148;) to acquire the gas utilities operated by Aquila in Colorado, Iowa, Kansas and Nebraska, and the electric utility operated by Aquila in Colorado, together with certain related assets, for $940 million in cash.  At the same time we entered into our agreements with Aquila, Aquila also entered into an agreement with Great Plains Energy Incorporated (&#147;Great Plains&#148;) for the merger of a subsidiary of Great Plains with and into Aquila.  Each transaction is contingent on the completion of the other transaction, meaning that one transaction will not be completed unless the other transaction is completed.</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:justify;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:justify;'><font size=2>The Agreement and Plan of Merger (&#147;Merger Agreement&#148;), the Asset Purchase Agreement (&#147;APA&#148;) and the Partnership Interests Purchase Agreement (&#147;PIPA&#148;), each dated February 6, 2007, provided they may be terminated if the transactions have not been consummated by February 6, 2008 (the &#147;Termination Date&#148;).  Each agreement further provides that if any party to the agreement determines that additional time is necessary to obtain any of the specified regulatory consents or approvals, the Termination Date may be extended from time to time by written notice, up to August 6, 2008.  Black Hills Corporation, Aquila and Great Plains previously extended the Termination Date under the agreements to May 1, 2008.</font><font size=1>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>On April 29, 2008, Black Hills Corporation, Aquila and Great Plains provided notices to each other again mutually extending the Termination Date under their APA, PIPA and Merger Agreement to August 6, 2008.</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>


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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><b><font size=2>Item 9.01</font></b></p> </td>
        <td width="253" nowrap valign=top style='padding:5.0pt 0in 5.0pt 0in; '>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><b><font size=2>Financial Statements and Exhibits</font></b></p> </td> </tr></table>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td width="48" valign=top style='padding:5.0pt 0in 5.0pt 0in'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>(d)</font></p> </td>
        <td  valign=top style='padding:5.0pt 0in 5.0pt 0in'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>Exhibits</font></p> </td> </tr></table>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>10</font></p> </td>
        <td width="577" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>Mutual Notice of Extension provided as of April 29, 2008, by and among Black Hills Corporation, Aquila, Inc., and Great Plains Energy Incorporated.</font></p> </td> </tr></table>
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<p style=' margin-bottom:0pt; margin-top:5pt; margin-left:0.25in;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:5pt; margin-left:1in; text-indent:-0.25in;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=2>2</font></p>
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<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><U><font SIZE=2>SIGNATURES</font></U></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt; text-indent:0.51in;text-align:left;'><font size=2>Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>


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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font SIZE=2>BLACK HILLS CORPORATION</font></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td width="319" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td width="319" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>By:&nbsp;</font><u><font size=2>/s/ Steven J. Helmers</font></u>                                                                                                                     </p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
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            <p style='margin-left:0pt;text-indent:21.0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>Steven J. Helmers</font></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
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            <p style='margin-left:0pt;text-indent:21.75pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>Senior Vice President</font></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td width="319" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:26.25pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>and General Counsel</font></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td width="319" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>Date:&nbsp;&nbsp;April 29, 2008</font></p> </td>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td> </tr></table>
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<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=2>3</font></p>
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<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'>
<font size=2>Exhibit Index</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:5pt; margin-top:5pt; margin-left:0.75in;text-align:left;'><font size=2>Exhibit #</font></p>


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        <td width="54" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>10</font></p> </td>
        <td width="505" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>Mutual Notice of Extension provided as of April 29, 2008, by and among Black Hills Corporation, Aquila, Inc., and Great Plains Energy Incorporated.</font></p> </td>
        <td width="505" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td> </tr></table>
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<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=2>4</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>
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<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>


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{"company-data": {"conformed-name": "BLACK HILLS CORP /SD/", "cik": "0001130464", "assigned-sic": "4911", "irs-number": "460458824", "state-of-incorporation": "SD", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "001-31303", "film-number": "08787385"}, "business-address": {"street1": "625 9TH STREET", "street2": "PO BOX 1400", "city": "RAPID CITY", "state": "SD", "zip": "57709", "phone": "6057212343"}, "mail-address": {"street1": "625 9TH STREET", "street2": "PO BOX 1400", "city": "RAPID", "state": "SD", "zip": "57709"}, "former-company": {"former-conformed-name": "BLACK HILLS HOLDING CORP", "date-changed": "20001222"}}
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
___________
FORM 8-K
____________
CURRENT REPORT
PURSUANT TO SECTION 13 OR 15(d) OF THE
SECURITIES EXCHANGE ACT OF 1934
Date of Report (Date of earliest event reported) April 29, 2008
____________
BLACK HILLS CORPORATION
(Exact name of registrant as specified in its charter)
____________
South Dakota
(State or other jurisdiction of incorporation)
001-31303
46-0458824
(Commission File Number)
(IRS Employer Identification No.)
625 Ninth Street, PO Box 1400
Rapid City, South Dakota
(Address of principal executive offices)
57709-1400
(Zip Code)
605.721.1700
(Registrant's telephone number, including area code)
Not Applicable
(Former name or former address, if changed since last report)
____________
Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (
see
General Instruction A.2. below):
Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
1
Item 1.01
Entry into a Material Definitive Agreement
On February 6, 2007, we entered into agreements with Aquila, Inc. ("Aquila") to acquire the gas utilities operated by Aquila in Colorado, Iowa, Kansas and Nebraska, and the electric utility operated by Aquila in Colorado, together with certain related assets, for $940 million in cash.  At the same time we entered into our agreements with Aquila, Aquila also entered into an agreement with Great Plains Energy Incorporated ("Great Plains") for the merger of a subsidiary of Great Plains with and into Aquila.  Each transaction is contingent on the completion of the other transaction, meaning that one transaction will not be completed unless the other transaction is completed.
The Agreement and Plan of Merger ("Merger Agreement"), the Asset Purchase Agreement ("APA") and the Partnership Interests Purchase Agreement ("PIPA"), each dated February 6, 2007, provided they may be terminated if the transactions have not been consummated by February 6, 2008 (the "Termination Date").  Each agreement further provides that if any party to the agreement determines that additional time is necessary to obtain any of the specified regulatory consents or approvals, the Termination Date may be extended from time to time by written notice, up to August 6, 2008.  Black Hills Corporation, Aquila and Great Plains previously extended the Termination Date under the agreements to May 1, 2008.
On April 29, 2008, Black Hills Corporation, Aquila and Great Plains provided notices to each other again mutually extending the Termination Date under their APA, PIPA and Merger Agreement to August 6, 2008.
Item 9.01
Financial Statements and Exhibits
(d)
Exhibits
10
Mutual Notice of Extension provided as of April 29, 2008, by and among Black Hills Corporation, Aquila, Inc., and Great Plains Energy Incorporated.
2
SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.
BLACK HILLS CORPORATION
By:
/s/ Steven J. Helmers
Steven J. Helmers
Senior Vice President
and General Counsel
Date:  April 29, 2008
3
Exhibit Index
Exhibit #
10
Mutual Notice of Extension provided as of April 29, 2008, by and among Black Hills Corporation, Aquila, Inc., and Great Plains Energy Incorporated.
4