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<SEC-DOCUMENT>0001193125-10-195124.txt : 20101018
<SEC-HEADER>0001193125-10-195124.hdr.sgml : 20101018
<ACCEPTANCE-DATETIME>20100823182929
<PRIVATE-TO-PUBLIC>
ACCESSION NUMBER:		0001193125-10-195124
CONFORMED SUBMISSION TYPE:	CORRESP
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20100823

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ADA-ES INC
		CENTRAL INDEX KEY:			0001223112
		STANDARD INDUSTRIAL CLASSIFICATION:	MISCELLANEOUS CHEMICAL PRODUCTS [2890]
		IRS NUMBER:				841457335
		STATE OF INCORPORATION:			CO
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		CORRESP

	MAIL ADDRESS:	
		STREET 1:		8100 SOUTHPARK WAY B
		CITY:			LITTLETON
		STATE:			CO
		ZIP:			80120
</SEC-HEADER>
<DOCUMENT>
<TYPE>CORRESP
<SEQUENCE>1
<FILENAME>filename1.htm
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<HTML><HEAD>
<TITLE>Correspondence Letter</TITLE>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2">August&nbsp;23, 2010 </FONT></P>
<P STYLE="margin-top:12px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B><I><U>VIA EDGAR and FEDERAL EXPRESS </U></I></B></FONT></P>
<P STYLE="margin-top:12px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Pamela Long, Assistant Director </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Division of
Corporation Finance </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">United States Securities and Exchange Commission </FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">100 F Street, N.E. </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Washington, D.C. 20549-7010
</FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Re:</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2">ADA-ES, Inc.</FONT></TD></TR>
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<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2">Amendment No. 1 to Registration Statement on Form S-3</FONT></TD></TR>
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<TD VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2">Originally Filed May 28, 2010</FONT></TD></TR>
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<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2"><U>SEC File No. 333-167188</U></FONT></TD></TR></TABLE> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Dear Ms.&nbsp;Long:
</FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">On behalf of ADA-ES, Inc. (&#147;we&#148; or the &#147;Company&#148;), we respond as follows to your facsimile and
attachments dated June&nbsp;18, 2010 (the &#147;Comment Letter&#148;) relating to the above-captioned registration statement on Form S-3. Captions and page references herein correspond to those set forth in Amendment No.&nbsp;1 to the registration
statement (&#147;Amendment No.&nbsp;1&#148; or the &#147;prospectus&#148;), a copy of which has been marked against the changes from the original filing of the Registration Statement, as filed on May&nbsp;28, 2010. </FONT></P>
<P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">Please note that the numbered responses below correspond to the numbered comments in the Comment Letter. </FONT></P>
<P STYLE="margin-top:18px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2"><U>Comments and Responses</U>: </FONT></P> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TR>
<TD WIDTH="4%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">1.</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">We have filed a post-effective amendment to the previous registration statement (SEC File No.&nbsp;333-119795) that included the 118,614 shares of ADA-ES Common Stock
that were issued to Arch Coal, Inc. in 2003, and that were originally registered therein. That post-effective amendment was filed on July&nbsp;2, 2010, and was declared effective on July&nbsp;7, 2010. Consequently, the 118,614 shares are no longer
registered in that offering and will be reregistered for sale in this registration statement. The description of the 2003 private placement in which the shares were originally registered, a reference to the registration statement in which the shares
were originally registered, together with a description of the deregistration of the shares from registration under that registration statement has been added to the second paragraph of the section of the prospectus entitled &#147;Private
Placements.&#148; See page 1 of Amendment No. 1 to the registration statement. </FONT></TD></TR></TABLE> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TD WIDTH="4%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">2.</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Filed with Amendment No.&nbsp;1 to the registration statement is a revised legal opinion that covers all of the shares being registered in the registration statement,
including the 118,614 shares of Common Stock originally issued to Arch Coal in 2003. See Exhibit 5.1 to the registration statement. </FONT></TD></TR></TABLE>

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 <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Pamela Long, Assistant Director </FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Securities&nbsp;&amp; Exchange Commission </FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">August&nbsp;23, 2010 </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Page 2 </FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">I believe that this responds to all of the Staff&#146;s comments. Please do not hesitate
to contact me if you have any further questions of comments. I can be reached at telephone 303-734-1727. </FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P><DIV ALIGN="right">
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<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Sincerely,</FONT></TD></TR>
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<TD HEIGHT="16"></TD></TR>
<TR>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">ADA-ES Inc.</FONT></TD></TR>
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<TD HEIGHT="16"></TD></TR>
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<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Mark H. McKinnies</FONT></P></TD></TR>
<TR>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Mark H. McKinnies,</FONT></TD></TR>
<TR>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Senior Vice President&nbsp;&amp; Chief Financial Officer</FONT></TD></TR></TABLE></DIV>
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