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<SEC-DOCUMENT>0000950123-09-046178.txt : 20090925
<SEC-HEADER>0000950123-09-046178.hdr.sgml : 20090925
<ACCEPTANCE-DATETIME>20090925165937
ACCESSION NUMBER:		0000950123-09-046178
CONFORMED SUBMISSION TYPE:	SC 13D
PUBLIC DOCUMENT COUNT:		2
FILED AS OF DATE:		20090925
DATE AS OF CHANGE:		20090925
GROUP MEMBERS:		YORKTOWN  VIII ASSOCIATES LLC
GROUP MEMBERS:		YORKTOWN ENERGY PARTNERS VIII, L.P.
GROUP MEMBERS:		YORKTOWN VIII COMPANY LP

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			HALLADOR PETROLEUM CO
		CENTRAL INDEX KEY:			0000788965
		STANDARD INDUSTRIAL CLASSIFICATION:	CRUDE PETROLEUM & NATURAL GAS [1311]
		IRS NUMBER:				841014610
		STATE OF INCORPORATION:			CO
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13D
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-37955
		FILM NUMBER:		091088154

	BUSINESS ADDRESS:	
		STREET 1:		1660 LINCOLN ST STE 2700
		CITY:			DENVER
		STATE:			CO
		ZIP:			80264
		BUSINESS PHONE:		3038395505

	MAIL ADDRESS:	
		STREET 1:		1660 LINCOLN STREET
		STREET 2:		SUITE 2700
		CITY:			DENVER
		STATE:			CO
		ZIP:			80264

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	KIMBARK OIL & GAS CO /CO/
		DATE OF NAME CHANGE:	19900102

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	KIMBARK INC
		DATE OF NAME CHANGE:	19860624

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Yorktown Energy Partners VIII, L.P.
		CENTRAL INDEX KEY:			0001473116
		IRS NUMBER:				262754039
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13D

	BUSINESS ADDRESS:	
		STREET 1:		410 PARK AVENUE
		STREET 2:		19TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
		BUSINESS PHONE:		(212) 515-2100

	MAIL ADDRESS:	
		STREET 1:		410 PARK AVENUE
		STREET 2:		19TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13D
<SEQUENCE>1
<FILENAME>c90546sc13d.htm
<DESCRIPTION>SCHEDULE 13D
<TEXT>
<HTML>
<HEAD>
<TITLE>Schedule 13D</TITLE>
</HEAD>
<BODY bgcolor="#FFFFFF">
<!-- PAGEBREAK -->
<DIV style="font-family: 'Times New Roman',Times,serif; margin-left: .25in; width: 7.20in">


<DIV style="font-size: 1pt; width: 100%; border-bottom: black 2pt solid"> </DIV> <DIV style="font-size: 1pt; width: 100%; border-bottom: black 1pt solid"> </DIV> <P align="center" style="font-size: 14pt"><B>UNITED STATES<BR>
SECURITIES AND EXCHANGE COMMISSION</B>

<DIV align="center" style="font-size: 12pt"><B>Washington, D.C. 20549</B>
</DIV>

<P align="center" style="font-size: 18pt"><B>SCHEDULE 13D</B>


<P align="center" style="font-size: 12pt"><B>Under the Securities Exchange Act of 1934<BR>
(Amendment No.&nbsp;&nbsp;)*</B>


<DIV align="center">
<DIV style="font-size: 24pt; margin-top: 16pt; width: 100%; border-bottom: 1px solid #000000">Hallador Petroleum Company</DIV>
</DIV>


<DIV align="center" style="font-size: 10pt">(Name of Issuer)
</DIV>


<DIV align="center">
<DIV style="font-size: 10pt; margin-top: 16pt; width: 100%; border-bottom: 1px solid #000000">Common Stock, par value $.01 per share</DIV>
</DIV>

<DIV align="center" style="font-size: 10pt">(Title of Class of Securities)
</DIV>


<DIV align="center">
<DIV style="font-size: 10pt; margin-top: 16pt; width: 100%; border-bottom: 1px solid #000000">406092304</DIV>
</DIV>

<DIV align="center" style="font-size: 10pt">(CUSIP Number)
</DIV>


<DIV align="center">
<DIV style="font-size: 10pt; margin-top: 16pt; width: 100%; border-bottom: 1px solid #000000">Bryan H. Lawrence<BR>
Yorktown Energy Partners VIII, L.P.<BR>410 Park Avenue<BR>19th Floor<BR>New York, New York 10022<BR>
(212) 515-2100<br> <br>Copies to:<br><br> Jeffrey A. Zlotky
<br>Thompson &#38; Knight LLP<br> One Arts Plaza <br>
1722 Routh Street, Suite 1500 <br>Dallas, Texas 75201-2533 <br>(214) 969-1700<BR></DIV>
</DIV>


<DIV align="center" style="font-size: 10pt">(Name, Address and Telephone Number of Person Authorized to<BR>
Receive Notices and Communications)
</DIV>


<DIV align="center">
<DIV style="font-size: 10pt; margin-top: 16pt; width: 100%; border-bottom: 1px solid #000000">September 15, 2009</DIV>
</DIV>

<DIV align="center" style="font-size: 10pt">(Date of Event Which Requires Filing of this Statement)
</DIV>

<P align="left" style="font-size: 10pt">If the filing person has previously filed a statement on Schedule&nbsp;13G to report the acquisition that is the subject of this Schedule&nbsp;13D, and is filing this schedule because of &#167;&#167;240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. <FONT face="wingdings" size="2">&#111;</FONT>

<P align="left" style="font-size: 10pt"><B>Note: </B>Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d-7 for other parties to whom copies are to be sent.

<P align="left" style="font-size: 10pt">* The remainder of this cover page shall be filled out for a reporting person&#146;s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

<P align="left" style="font-size: 10pt">The information required on the remainder of this cover page shall not be deemed to be &#147;filed&#148; for the purpose of Section 18 of the Securities Exchange Act of 1934 (&#147;Act&#148;) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).


<DIV style="width: 100%; border-bottom: 1pt solid black; margin-top: 10pt; font-size: 1pt">&nbsp;</DIV>
<DIV style="width: 100%; border-bottom: 2pt solid black; font-size: 1pt">&nbsp;</DIV>

<P align="center" style="font-size: 10pt">
</DIV>
<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always">&nbsp;</H5><P>
<DIV style="font-family: 'Times New Roman',Times,serif; margin-left: .25in; width: 7.20in">

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
<TD width="1%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="20%">&nbsp;</TD>
<TD width="55%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="9%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="9%">&nbsp;</TD>
</TR>
<!-- End Table Head -->
<!-- Begin Table Body -->


<TR valign="bottom">
<TD valign="top" nowrap><DIV style="margin-left:0px; text-indent:-0px">CUSIP No.</DIV></TD>
<TD>&nbsp;</TD>
<TD align="center" valign="top"><DIV style="border: 1px solid #000000">406092304&nbsp;</DIV></TD>
<TD>&nbsp;</TD>
</TR>
<!-- End Table Body -->
</TABLE>
</DIV>

<P>&nbsp;<DIV style="width: 100%; border: 1px solid black"><DIV align="center">

<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="1" width="100%">
<!-- Begin Table Head --><TR style="font-size: 1px">
<TD width="5%">&nbsp;</TD>
<TD width="1%" style="border-left: 1px solid #000000">&nbsp;</TD>
<TD width="5%">&nbsp;</TD>
<TD width="5%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="83%">&nbsp;</TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom">
<TD valign="middle" align="center"><FONT style="font-size: 18pt"><B>1</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">NAMES OF REPORTING PERSONS<BR>
<BR>
YORKTOWN ENERGY PARTNERS VIII, L.P.</TD>
</TR>
<TR valign="bottom">
<TD>&nbsp;</TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>2</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)<BR><BR></TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">(a)&nbsp;&nbsp;&nbsp;<FONT face="wingdings" size="2">&#111;</FONT>&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">(b)&nbsp;&nbsp;&nbsp;<FONT face="wingdings" size="2">&#111;</FONT>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>3</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">SEC USE ONLY</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>4</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">SOURCE OF FUNDS (SEE INSTRUCTIONS)</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="11" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="11" align="left">OO</TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>5</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left"><FONT face="wingdings" size="2">&#111;</FONT></TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>6</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">CITIZENSHIP OR PLACE OF ORGANIZATION</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">Delaware
</TD>
</TR>

<TR style="font-size: 1px">
<TD colspan="3" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000; border-left: 1px solid #000000; border-right: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD align="center" colspan="3">&nbsp;</TD>
<TD valign="middle" align="center" rowspan="3" style="border-left: 1px solid #000000; border-right: 1px solid #000000"><FONT style="font-size: 18pt"><B>7</B></FONT></TD>
<TD>&nbsp;</TD>
<TD align="left">SOLE VOTING POWER</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">&nbsp;</TD>
<TD>&nbsp;</TD>
<TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">NUMBER OF</TD>
<TD>&nbsp;</TD>
<TD align="left">2,950,000</TD>
</TR>

<TR style="font-size: 1px">
<TD colspan="3">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000; border-left: 1px solid #000000; border-right: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD align="center" colspan="3">SHARES</TD>
<TD valign="middle" align="center" rowspan="3" style="border-left: 1px solid #000000; border-right: 1px solid #000000"><FONT style="font-size: 18pt"><B>8</B></FONT></TD>
<TD>&nbsp;</TD>
<TD align="left">SHARED VOTING POWER</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">BENEFICIALLY</TD>
<TD>&nbsp;</TD>
<TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">OWNED BY</TD>
<TD>&nbsp;</TD>
<TD>0</TD>
</TR>

<TR style="font-size: 1px">
<TD colspan="3">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000; border-left: 1px solid #000000; border-right: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>


<TR valign="bottom">
<TD align="center" colspan="3">EACH</TD>
<TD valign="middle" align="center" rowspan="3" style="border-left: 1px solid #000000; border-right: 1px solid #000000"><FONT style="font-size: 18pt"><B>9</B></FONT></TD>
<TD>&nbsp;</TD>
<TD align="left">SOLE DISPOSITIVE POWER</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">REPORTING</TD>
<TD>&nbsp;</TD>
<TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">PERSON</TD>
<TD>&nbsp;</TD>
<TD align="left">2,950,000</TD>
</TR>
<TR style="font-size: 1px">
<TD colspan="3">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000; border-left: 1px solid #000000; border-right: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD align="center" colspan="3">WITH</TD>
<TD valign="middle" align="center" rowspan="3" style="border-left: 1px solid #000000; border-right: 1px solid #000000"><FONT style="font-size: 18pt"><B>10</B></FONT></TD>
<TD>&nbsp;</TD>
<TD align="left">SHARED DISPOSITIVE POWER</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">&nbsp;</TD>
<TD>&nbsp;</TD>
<TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">&nbsp;</TD>
<TD>&nbsp;</TD>
<TD align="left">0</TD>
</TR>
<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>11</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">2,950,000 (1)</TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>12</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">CHECK IF THE AGGREGATE AMOUNT IN ROW (11)&nbsp;EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left"><FONT face="wingdings" size="2">&#111;</FONT>
</TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>13</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">11.1&#37;(2)</TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>14</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">PN</TD>
</TR>
<!-- End Table Body --></TABLE>
</DIV>
</DIV>

<DIV style="font-size: 10pt; margin-top: 3pt">(1) Yorktown VIII Company LP is the sole general partner of Yorktown Energy Partners VIII, L.P. Yorktown VIII Associates LLC is the sole general partner of Yorktown VIII Company LP. As a result, Yorktown VIII Associates LLC may be deemed to have the power to vote or direct the vote or to dispose or direct the disposition of the shares owned by Yorktown Energy Partners VIII, L.P. Yorktown VIII Company LP and Yorktown VIII Associates LLC disclaim beneficial ownership of the securities owned by Yorktown Energy Partners VIII, L.P. in excess of their pecuniary interests therein.
</DIV>

<DIV style="font-size: 10pt; margin-top: 3pt">(2) Based on 26,608,028 shares of common stock issued and outstanding as of September 15, 2009, as confirmed by Hallador Petroleum Company.
</DIV>

<DIV style="font-size: 10pt; margin-top: 3pt">
</DIV>

<DIV style="font-size: 10pt; margin-top: 3pt">
</DIV>


<P align="center" style="font-size: 10pt">



</DIV>
<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always">&nbsp;</H5><P>
<DIV style="font-family: 'Times New Roman',Times,serif; margin-left: .25in; width: 7.20in">

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
<TD width="1%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="20%">&nbsp;</TD>
<TD width="55%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="9%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="9%">&nbsp;</TD>
</TR>
<!-- End Table Head -->
<!-- Begin Table Body -->


<TR valign="bottom">
<TD valign="top" nowrap><DIV style="margin-left:0px; text-indent:-0px">CUSIP No.</DIV></TD>
<TD>&nbsp;</TD>
<TD align="center" valign="top"><DIV style="border: 1px solid #000000">406092304&nbsp;</DIV></TD>
<TD>&nbsp;</TD>
</TR>
<!-- End Table Body -->
</TABLE>
</DIV>

<P>&nbsp;<DIV style="width: 100%; border: 1px solid black"><DIV align="center">

<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="1" width="100%">
<!-- Begin Table Head --><TR style="font-size: 1px">
<TD width="5%">&nbsp;</TD>
<TD width="1%" style="border-left: 1px solid #000000">&nbsp;</TD>
<TD width="5%">&nbsp;</TD>
<TD width="5%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="83%">&nbsp;</TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom">
<TD valign="middle" align="center"><FONT style="font-size: 18pt"><B>1</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">NAMES OF REPORTING PERSONS<BR>
<BR>
YORKTOWN VIII COMPANY LP</TD>
</TR>
<TR valign="bottom">
<TD>&nbsp;</TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>2</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)<BR><BR></TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">(a)&nbsp;&nbsp;&nbsp;<FONT face="wingdings" size="2">&#111;</FONT>&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">(b)&nbsp;&nbsp;&nbsp;<FONT face="wingdings" size="2">&#111;</FONT>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>3</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">SEC USE ONLY</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>4</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">SOURCE OF FUNDS (SEE INSTRUCTIONS)</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="11" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="11" align="left">OO</TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>5</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left"><FONT face="wingdings" size="2">&#111;</FONT></TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>6</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">CITIZENSHIP OR PLACE OF ORGANIZATION</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">Delaware
</TD>
</TR>

<TR style="font-size: 1px">
<TD colspan="3" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000; border-left: 1px solid #000000; border-right: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD align="center" colspan="3">&nbsp;</TD>
<TD valign="middle" align="center" rowspan="3" style="border-left: 1px solid #000000; border-right: 1px solid #000000"><FONT style="font-size: 18pt"><B>7</B></FONT></TD>
<TD>&nbsp;</TD>
<TD align="left">SOLE VOTING POWER</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">&nbsp;</TD>
<TD>&nbsp;</TD>
<TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">NUMBER OF</TD>
<TD>&nbsp;</TD>
<TD align="left">2,950,000</TD>
</TR>

<TR style="font-size: 1px">
<TD colspan="3">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000; border-left: 1px solid #000000; border-right: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD align="center" colspan="3">SHARES</TD>
<TD valign="middle" align="center" rowspan="3" style="border-left: 1px solid #000000; border-right: 1px solid #000000"><FONT style="font-size: 18pt"><B>8</B></FONT></TD>
<TD>&nbsp;</TD>
<TD align="left">SHARED VOTING POWER</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">BENEFICIALLY</TD>
<TD>&nbsp;</TD>
<TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">OWNED BY</TD>
<TD>&nbsp;</TD>
<TD>0</TD>
</TR>

<TR style="font-size: 1px">
<TD colspan="3">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000; border-left: 1px solid #000000; border-right: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>


<TR valign="bottom">
<TD align="center" colspan="3">EACH</TD>
<TD valign="middle" align="center" rowspan="3" style="border-left: 1px solid #000000; border-right: 1px solid #000000"><FONT style="font-size: 18pt"><B>9</B></FONT></TD>
<TD>&nbsp;</TD>
<TD align="left">SOLE DISPOSITIVE POWER</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">REPORTING</TD>
<TD>&nbsp;</TD>
<TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">PERSON</TD>
<TD>&nbsp;</TD>
<TD align="left">2,950,000</TD>
</TR>
<TR style="font-size: 1px">
<TD colspan="3">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000; border-left: 1px solid #000000; border-right: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD align="center" colspan="3">WITH</TD>
<TD valign="middle" align="center" rowspan="3" style="border-left: 1px solid #000000; border-right: 1px solid #000000"><FONT style="font-size: 18pt"><B>10</B></FONT></TD>
<TD>&nbsp;</TD>
<TD align="left">SHARED DISPOSITIVE POWER</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">&nbsp;</TD>
<TD>&nbsp;</TD>
<TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">&nbsp;</TD>
<TD>&nbsp;</TD>
<TD align="left">0</TD>
</TR>
<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>11</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">2,950,000 (1)</TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>12</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">CHECK IF THE AGGREGATE AMOUNT IN ROW (11)&nbsp;EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left"><FONT face="wingdings" size="2">&#111;</FONT>
</TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>13</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">11.1&#37;(2)</TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>14</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">PN</TD>
</TR>
<!-- End Table Body --></TABLE>
</DIV>
</DIV>

<DIV style="font-size: 10pt; margin-top: 3pt">(1) Yorktown VIII Company LP is the sole general partner of Yorktown Energy Partners VIII, L.P. Yorktown VIII Associates LLC is the sole general partner of Yorktown VIII Company LP. As a result, Yorktown VIII Associates LLC may be deemed to have the power to vote or direct the vote or to dispose or direct the disposition of the shares owned by Yorktown Energy Partners VIII, L.P. Yorktown VIII Company LP and Yorktown VIII Associates LLC disclaim beneficial ownership of the securities owned by Yorktown Energy Partners VIII, L.P. in excess of their pecuniary interests therein.
</DIV>

<DIV style="font-size: 10pt; margin-top: 3pt">(2) Based on 26,608,028 shares of common stock issued and outstanding as of September 15, 2009, as confirmed by Hallador Petroleum Company.
</DIV>

<DIV style="font-size: 10pt; margin-top: 3pt">
</DIV>

<DIV style="font-size: 10pt; margin-top: 3pt">
</DIV>


<P align="center" style="font-size: 10pt">



</DIV>
<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always">&nbsp;</H5><P>
<DIV style="font-family: 'Times New Roman',Times,serif; margin-left: .25in; width: 7.20in">

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
<TD width="1%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="20%">&nbsp;</TD>
<TD width="55%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="9%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="9%">&nbsp;</TD>
</TR>
<!-- End Table Head -->
<!-- Begin Table Body -->


<TR valign="bottom">
<TD valign="top" nowrap><DIV style="margin-left:0px; text-indent:-0px">CUSIP No.</DIV></TD>
<TD>&nbsp;</TD>
<TD align="center" valign="top"><DIV style="border: 1px solid #000000">406092304&nbsp;</DIV></TD>
<TD>&nbsp;</TD>
</TR>
<!-- End Table Body -->
</TABLE>
</DIV>

<P>&nbsp;<DIV style="width: 100%; border: 1px solid black"><DIV align="center">

<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="1" width="100%">
<!-- Begin Table Head --><TR style="font-size: 1px">
<TD width="5%">&nbsp;</TD>
<TD width="1%" style="border-left: 1px solid #000000">&nbsp;</TD>
<TD width="5%">&nbsp;</TD>
<TD width="5%">&nbsp;</TD>
<TD width="1%">&nbsp;</TD>
<TD width="83%">&nbsp;</TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom">
<TD valign="middle" align="center"><FONT style="font-size: 18pt"><B>1</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">NAMES OF REPORTING PERSONS<BR>
<BR>
YORKTOWN  VIII ASSOCIATES LLC</TD>
</TR>
<TR valign="bottom">
<TD>&nbsp;</TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>2</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)<BR><BR></TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">(a)&nbsp;&nbsp;&nbsp;<FONT face="wingdings" size="2">&#111;</FONT>&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">(b)&nbsp;&nbsp;&nbsp;<FONT face="wingdings" size="2">&#111;</FONT>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>3</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">SEC USE ONLY</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>4</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">SOURCE OF FUNDS (SEE INSTRUCTIONS)</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="11" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="11" align="left">OO</TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>5</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left"><FONT face="wingdings" size="2">&#111;</FONT></TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>6</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">CITIZENSHIP OR PLACE OF ORGANIZATION</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">Delaware
</TD>
</TR>

<TR style="font-size: 1px">
<TD colspan="3" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000; border-left: 1px solid #000000; border-right: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD align="center" colspan="3">&nbsp;</TD>
<TD valign="middle" align="center" rowspan="3" style="border-left: 1px solid #000000; border-right: 1px solid #000000"><FONT style="font-size: 18pt"><B>7</B></FONT></TD>
<TD>&nbsp;</TD>
<TD align="left">SOLE VOTING POWER</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">&nbsp;</TD>
<TD>&nbsp;</TD>
<TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">NUMBER OF</TD>
<TD>&nbsp;</TD>
<TD align="left">2,950,000</TD>
</TR>

<TR style="font-size: 1px">
<TD colspan="3">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000; border-left: 1px solid #000000; border-right: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD align="center" colspan="3">SHARES</TD>
<TD valign="middle" align="center" rowspan="3" style="border-left: 1px solid #000000; border-right: 1px solid #000000"><FONT style="font-size: 18pt"><B>8</B></FONT></TD>
<TD>&nbsp;</TD>
<TD align="left">SHARED VOTING POWER</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">BENEFICIALLY</TD>
<TD>&nbsp;</TD>
<TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">OWNED BY</TD>
<TD>&nbsp;</TD>
<TD>0</TD>
</TR>

<TR style="font-size: 1px">
<TD colspan="3">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000; border-left: 1px solid #000000; border-right: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>


<TR valign="bottom">
<TD align="center" colspan="3">EACH</TD>
<TD valign="middle" align="center" rowspan="3" style="border-left: 1px solid #000000; border-right: 1px solid #000000"><FONT style="font-size: 18pt"><B>9</B></FONT></TD>
<TD>&nbsp;</TD>
<TD align="left">SOLE DISPOSITIVE POWER</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">REPORTING</TD>
<TD>&nbsp;</TD>
<TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">PERSON</TD>
<TD>&nbsp;</TD>
<TD align="left">2,950,000</TD>
</TR>
<TR style="font-size: 1px">
<TD colspan="3">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000; border-left: 1px solid #000000; border-right: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
<TD align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD align="center" colspan="3">WITH</TD>
<TD valign="middle" align="center" rowspan="3" style="border-left: 1px solid #000000; border-right: 1px solid #000000"><FONT style="font-size: 18pt"><B>10</B></FONT></TD>
<TD>&nbsp;</TD>
<TD align="left">SHARED DISPOSITIVE POWER</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">&nbsp;</TD>
<TD>&nbsp;</TD>
<TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD align="center" colspan="3">&nbsp;</TD>
<TD>&nbsp;</TD>
<TD align="left">0</TD>
</TR>
<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>11</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">2,950,000 (1)</TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>12</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">CHECK IF THE AGGREGATE AMOUNT IN ROW (11)&nbsp;EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left"><FONT face="wingdings" size="2">&#111;</FONT>
</TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>13</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">11.1&#37;(2)</TD>
</TR>

<TR style="font-size: 1px">
<TD style="border-top: 1px solid #000000">&nbsp;</TD>
<TD style="border-left: 1px solid #000000; border-top: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left" style="border-top: 1px solid #000000">&nbsp;</TD>
</TR>

<TR valign="bottom">
<TD valign="middle" align="center" rowspan="3"><FONT style="font-size: 18pt"><B>14</B></FONT></TD>
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">&nbsp;</TD>
</TR>
<TR valign="bottom">
<TD style="border-left: 1px solid #000000">&nbsp;</TD>
<TD colspan="4" align="left">OO</TD>
</TR>
<!-- End Table Body --></TABLE>
</DIV>
</DIV>

<DIV style="font-size: 10pt; margin-top: 3pt">(1) Yorktown VIII Company LP is the sole general partner of Yorktown Energy Partners VIII, L.P. Yorktown VIII Associates LLC is the sole general partner of Yorktown VIII Company LP. As a result, Yorktown VIII Associates LLC may be deemed to have the power to vote or direct the vote or to dispose or direct the disposition of the shares owned by Yorktown Energy Partners VIII, L.P. Yorktown VIII Company LP and Yorktown VIII Associates LLC disclaim beneficial ownership of the securities owned by Yorktown Energy Partners VIII, L.P. in excess of their pecuniary interests therein.
</DIV>

<DIV style="font-size: 10pt; margin-top: 3pt">(2) Based on 26,608,028 shares of common stock issued and outstanding as of September 15, 2009, as confirmed by Hallador Petroleum Company.
</DIV>

<DIV style="font-size: 10pt; margin-top: 3pt">
</DIV>

<DIV style="font-size: 10pt; margin-top: 3pt">
</DIV>


<P align="center" style="font-size: 10pt">



</DIV>
<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always">&nbsp;</H5><P>
<DIV style="font-family: 'Times New Roman',Times,serif; margin-left: .25in; width: 7.20in">

<DIV align="justify" style="font-size: 10pt; margin-top: 10pt"><B>Item&nbsp;1. Security and Issuer.</B>
</DIV>


<DIV align="justify" style="font-size: 10pt; margin-top: 10pt; text-indent: 4%">This Schedule&nbsp;13D relates to the common stock, par value $.01 per share (the &#147;Common Stock&#148;),
of Hallador Petroleum Company (the &#147;Company&#148;) whose principal executive offices are located at 1660
Lincoln Street, Suite&nbsp;2700, Denver, Colorado 80264.
</DIV>

<DIV align="justify" style="font-size: 10pt; margin-top: 10pt"><B>Item&nbsp;2. Identity and Background.</B>
</DIV>


<DIV align="justify" style="font-size: 10pt; margin-top: 10pt; text-indent: 4%">This statement is filed by Yorktown Energy Partners VIII, L.P., a Delaware limited partnership
(&#147;Yorktown&#148;), Yorktown VIII Company LP, a Delaware limited partnership (&#147;Yorktown Company&#148;) and
Yorktown VIII Associates LLC, a Delaware limited liability company (&#147;Yorktown Associates&#148;). The
principal office and business address of Yorktown, Yorktown Company and Yorktown Associates is 410
Park Avenue, 19th Floor, New York, New York 10022. The principal business of Yorktown is investing
in equity securities of energy companies. The principal business of Yorktown Company is managing
Yorktown. The principal business of Yorktown Associates is managing Yorktown Company.
</DIV>

<DIV align="justify" style="font-size: 10pt; margin-top: 10pt; text-indent: 4%">Yorktown, Yorktown Company and Yorktown Associates have not, during the last five years, been
convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors).
</DIV>

<DIV align="justify" style="font-size: 10pt; margin-top: 10pt; text-indent: 4%">Yorktown, Yorktown Company and Yorktown Associates have not, during the last five years, been
a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as
a result of such proceeding was or is subject to a judgment, decree or final order enjoining future
violations of, or prohibiting or mandating activities subject to, federal or state securities laws
or finding any violation with respect to such laws.
</DIV>

<DIV align="justify" style="font-size: 10pt; margin-top: 10pt"><B>Item&nbsp;3. Source and Amount of Funds or Other Consideration.</B>
</DIV>


<DIV align="justify" style="font-size: 10pt; margin-top: 10pt; text-indent: 4%">Yorktown used $17,700,000 of partnership funds to purchase 2,950,000 shares of Common Stock on
September&nbsp;15, 2009.
</DIV>

<DIV align="justify" style="font-size: 10pt; margin-top: 10pt"><B>Item&nbsp;4. Purpose of Transaction.</B>
</DIV>


<DIV align="justify" style="font-size: 10pt; margin-top: 10pt; text-indent: 4%">Yorktown acquired its 2,950,000 shares of Common Stock for investment purposes. As of the
date hereof, Yorktown, Yorktown Company and Yorktown Associates have not formulated any specific
plans or proposals which relate to or would result in: (a)&nbsp;the acquisition by any person of
additional securities of the Company or the disposition of securities of the Company; (b)&nbsp;an
extraordinary corporate transaction, such as a merger, reorganization or liquidation involving the
Company or any of its subsidiaries; (c)&nbsp;a sale or transfer of a material amount of assets of the
Company or any of its subsidiaries; (d)&nbsp;any change in the present board of directors or management
of the Company, including any plans or proposals to change the number or term of directors or to
fill any existing vacancies on the board of the Company; (e)&nbsp;any material change in the present
capitalization or dividend policy of the Company; (f)&nbsp;any other material change in the Company&#146;s
business or corporate structure; (g)&nbsp;changes in the Company&#146;s charter, bylaws or instruments
corresponding thereto or other actions which may impede the acquisition of control of the Company
by any person; (h)&nbsp;causing a class of securities of the Company to be delisted from a national
securities exchange or to cease to be authorized to
be quoted in an inter-dealer quotation system of a registered national securities association; (i)
causing a class of equity securities of the Company to become eligible for termination of
registration pursuant to Section&nbsp;12(g)(4) of the Securities Exchange Act of 1934, as amended; or
(j)&nbsp;any action similar to any of those enumerated above.
</DIV>

<DIV align="justify" style="font-size: 10pt; margin-top: 10pt"><B>Item&nbsp;5. Interest in Securities of the Issuer.</B>
</DIV>


<DIV style="margin-top: 10pt">
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">
<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="4%" style="background: transparent">&nbsp;</TD>
    <TD width="3%" nowrap align="left">(a)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><DIV style="text-align: justify">As of September&nbsp;24, 2009, Yorktown, Yorktown Company and Yorktown Associates
beneficially owned 2,950,000 shares of Common Stock, representing 11.1% of the
Company&#146;s outstanding shares of common stock (based on 26,608,028 shares of Common
Stock issued and outstanding as of September&nbsp;15, 2009, as confirmed by Hallador
Petroleum Company).</DIV></TD>
</TR>

</TABLE>
</DIV>
<P align="center" style="font-size: 10pt">&nbsp;

<P align="center" style="font-size: 10pt"><!-- Folio -->&nbsp;<!-- /Folio -->
</DIV>

<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always">&nbsp;</H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif; margin-left: .25in; width: 7.20in">

<DIV style="margin-top: 10pt"><TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">


</TABLE>
</DIV>

<DIV style="margin-top: 10pt">
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">
<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="4%" style="background: transparent">&nbsp;</TD>
    <TD width="3%" nowrap align="left">(b)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><DIV style="text-align: justify">Yorktown VIII Company LP is the sole general partner of Yorktown Energy
Partners VIII, L.P. Yorktown VIII Associates LLC is the sole general partner of
Yorktown VIII Company LP. Yorktown Associates has the sole power to cause Yorktown
Company to cause Yorktown to vote or direct the vote or to dispose or direct the
disposition of the shares owned by Yorktown.</DIV></TD>
</TR>

<TR style="font-size: 8pt">
    <TD>&nbsp;</TD>
</TR> <TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="4%" style="background: transparent">&nbsp;</TD>
    <TD width="3%" nowrap align="left">(c)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><DIV style="text-align: justify">On September&nbsp;15, 2009, Yorktown acquired from the Company 2,950,000 shares of
Common Stock for $6.00 per share for an aggregate price of $17,700,000 through a
private placement exempt from the registration requirements of the Securities Act of
1933, as amended.</DIV></TD>
</TR>

<TR style="font-size: 8pt">
    <TD>&nbsp;</TD>
</TR> <TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="4%" style="background: transparent">&nbsp;</TD>
    <TD width="3%" nowrap align="left">(d)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><DIV style="text-align: justify">No person other than Yorktown has the right to receive or the power to direct
the receipt of dividends from, or the proceeds from the sale of, the shares of Common
Stock reported on this Schedule&nbsp;13D.</DIV></TD>
</TR>

<TR style="font-size: 8pt">
    <TD>&nbsp;</TD>
</TR> <TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="4%" style="background: transparent">&nbsp;</TD>
    <TD width="3%" nowrap align="left">(e)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><DIV style="text-align: justify">Inapplicable.</DIV></TD>
</TR>

</TABLE>
</DIV>

<DIV align="justify" style="font-size: 10pt; margin-top: 10pt"><B>Item&nbsp;6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer.</B>
</DIV>



<DIV align="justify" style="font-size: 10pt; margin-top: 10pt; margin-left: 4%">None.
</DIV>

<DIV align="justify" style="font-size: 10pt; margin-top: 10pt"><B>Item&nbsp;7. Material to Be Filed as Exhibits.</B>
</DIV>



<DIV align="justify" style="font-size: 10pt; margin-top: 10pt; margin-left: 4%">Exhibit&nbsp;1&nbsp;&nbsp;&nbsp;&#151;&nbsp;&nbsp;&nbsp;Joint Filing Agreement dated September&nbsp;25, 2009
</DIV>
<P align="center" style="font-size: 10pt">&nbsp;

<P align="center" style="font-size: 10pt"><!-- Folio -->&nbsp;<!-- /Folio -->
</DIV>

<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always">&nbsp;</H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif; margin-left: .25in; width: 7.20in">

<DIV align="center" style="font-size: 10pt; margin-top: 10pt">SIGNATURES
</DIV>


<DIV align="justify" style="font-size: 10pt; margin-top: 10pt; text-indent: 4%">After reasonable inquiry and to the best of my knowledge and belief, I certify that the
information set forth in this statement is true, complete and correct.
</DIV>

<DIV align="justify" style="font-size: 10pt; margin-top: 10pt">Date: September&nbsp;25, 2009
</DIV>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head --><TR valign="bottom">
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="35%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="62%">&nbsp;</TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom">
    <TD nowrap colspan="3" valign="top" align="left">YORKTOWN ENERGY PARTNERS VIII, L.P.</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">By:
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Yorktown VIII Company LP,</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">its general partner</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">By:
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Yorktown VIII Associates LLC,</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">its general partner</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">By:
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">/s/ Bryan H. Lawrence
<DIV style="font-size: 1pt; border-top: 1px solid #000000">&nbsp;</DIV>
Bryan H. Lawrence, Member
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD colspan="3" valign="top" align="left">YORKTOWN VIII COMPANY LP</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">By:
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Yorktown VIII Associates LLC,</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">its general partner</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">By:
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">/s/ Bryan H. Lawrence
<DIV style="font-size: 1pt; border-top: 1px solid #000000">&nbsp;</DIV>
Bryan H. Lawrence, Member
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD colspan="3" valign="top" align="left">YORKTOWN VIII ASSOCIATES LLC</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">By:
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">/s/ Bryan H. Lawrence
<DIV style="font-size: 1pt; border-top: 1px solid #000000">&nbsp;</DIV>
Bryan H. Lawrence, Member
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;&nbsp;</TD>
</TR>
<!-- End Table Body --></TABLE>
</DIV>


<P align="center" style="font-size: 10pt">&nbsp;

<P align="center" style="font-size: 10pt"><!-- Folio -->&nbsp;<!-- /Folio -->
</DIV>

<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always">&nbsp;</H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif; margin-left: .25in; width: 7.20in">

<DIV align="center" style="font-size: 10pt; margin-top: 10pt">EXHIBIT INDEX
</DIV>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head --><TR valign="bottom">
    <TD width="5%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="86%">&nbsp;</TD>
</TR>
<TR style="font-size: 10pt" valign="bottom">
    <TD nowrap align="left" style="border-bottom: 1px solid #000000"><B>Exhibit No.</B></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="left" style="border-bottom: 1px solid #000000"><B>Description</B></TD>
</TR>


<!-- End Table Head -->
<!-- Begin Table Body -->
<TR>
<TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">Exhibit&nbsp;1
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&#151;
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Joint Filing Agreement dated
September&nbsp;25, 2009</TD>
</TR>
<!-- End Table Body --></TABLE>
</DIV>


<P align="center" style="font-size: 10pt">&nbsp;

<P align="center" style="font-size: 10pt"><!-- Folio -->&nbsp;<!-- /Folio -->
</DIV>

</BODY>
</HTML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-99.1
<SEQUENCE>2
<FILENAME>c90546exv99w1.htm
<DESCRIPTION>EXHIBIT 1
<TEXT>
<HTML>
<HEAD>
<TITLE>Exhibit 1</TITLE>
</HEAD>
<BODY bgcolor="#FFFFFF">
<!-- PAGEBREAK -->

<DIV style="font-family: 'Times New Roman',Times,serif; margin-left: .25in; width: 7.20in">

<DIV align="right" style="font-size: 10pt; margin-top: 10pt">EXHIBIT 1
</DIV>


<DIV align="center" style="font-size: 10pt; margin-top: 10pt">JOINT FILING AGREEMENT
</DIV>


<DIV align="justify" style="font-size: 10pt; margin-top: 10pt; text-indent: 4%">In accordance with Rule&nbsp;13d-1(k) promulgated under the Securities Exchange Act of 1934, as
amended, the undersigned persons hereby agree to the joint filing on behalf of each of them of a
statement on Schedule&nbsp;13D (including amendments thereto) with respect to the common stock of
HALLADOR PETROLEUM COMPANY and further agree that this Joint Filing Agreement be included as an
Exhibit to such joint filing. In evidence thereof each of the undersigned, being duly authorized,
hereby execute this Agreement on the date set forth below.
</DIV>

<DIV align="justify" style="font-size: 10pt; margin-top: 10pt">Date: September&nbsp;25, 2009
</DIV>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head --><TR valign="bottom">
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="35%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="62%">&nbsp;</TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom">
    <TD nowrap colspan="3" valign="top" align="left">YORKTOWN ENERGY PARTNERS VIII, L.P.</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">By:
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Yorktown VIII Company LP,</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">its general partner</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">By:
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Yorktown VIII Associates LLC,</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">its general partner</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">By:
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">/s/ Bryan H. Lawrence
<DIV style="font-size: 1pt; border-top: 1px solid #000000">&nbsp;</DIV>
Bryan H. Lawrence, Member
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD colspan="3" valign="top" align="left">YORKTOWN VIII COMPANY LP</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">By:
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Yorktown VIII Associates LLC,</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">its general partner</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">By:
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">/s/ Bryan H. Lawrence
<DIV style="font-size: 1pt; border-top: 1px solid #000000">&nbsp;</DIV>
Bryan H. Lawrence, Member
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD colspan="3" valign="top" align="left">YORKTOWN VIII ASSOCIATES LLC</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom" style="padding-top: 1px">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">By:
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">/s/ Bryan H. Lawrence
<DIV style="font-size: 1pt; border-top: 1px solid #000000">&nbsp;</DIV>
Bryan H. Lawrence, Member
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;&nbsp;</TD>
</TR>
<!-- End Table Body --></TABLE>
</DIV>



<P align="center" style="font-size: 10pt">&nbsp;

<P align="center" style="font-size: 10pt"><!-- Folio -->&nbsp;<!-- /Folio -->
</DIV>



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