Exhibit 31.1

Certification
of Chief Executive Officer of ADA-ES, Inc. Pursuant to  Rules 13a-14(a) and 15d-14(a) of
the Securities Exchange Act of 1934, as  Amended

I, Michael  D.
Durham, President and Chief Executive Officer of ADA-ES, Inc. (the
"registrant") certify that:

1.   I have
reviewed this Annual Report on  Form 10-K of ADA-ES, Inc.;

2.   Based on my
knowledge, this report does  not contain any untrue statement of a material  fact or omit
to state a material  fact necessary to make the statements made, in light of  the
circumstances under  which such statements were made, not misleading with respect to  the
period  covered by this report;

3.   Based on my
knowledge, the financial  statements, and other financial information  included in this
report, fairly  present in all material respects the financial  condition, results of
operations  and cash flows of the registrant as of, and for, the  periods presented in
this  report;

4.   The
registrants other certifying  officer and I are responsible for establishing  and
maintaining disclosure  controls and procedures (as defined in Exchange Act Rules
13a-15(e) and  15d-15(e)) and internal control over financial reporting (as defined in
Exchange  Act Rules 13a-15(f) and 15d-15(f)) for the registrant and  have:

(a)   Designed
such  disclosure controls  and procedures, or caused such disclosure controls  and
procedures to be designed under  our supervision, to ensure that material  information
relating to the registrant,  including its consolidated  subsidiaries, is  made known to
us by others within those  entities,  particularly during the period in  which this
report is being  prepared;

(b)   Designed
such  internal control over financial reporting, or caused such internal control  over
financial reporting to be designed under our supervision, to provide  reasonable
assurance regarding the reliability of financial reporting and  the preparation of
financial statements for external purposes in  accordance with generally accepted
accounting  principles;

(c)   
Evaluated the  effectiveness of  the registrant's disclosure controls and procedures and
presented in this report our  conclusions about the effectiveness of the  disclosure
controls and procedures, as of the  end of the period covered by  this report based on
such evaluation;  and

(d)   
Disclosed in this  report any  change in the registrant's internal control over financial
reporting that occurred  during the registrant's most recent fiscal quarter  (the
registrants fourth fiscal  quarter in the case of an annual report)  that has
materially affected, or is reasonably  likely to materially  affect, the registrants
internal control over financial  reporting;  and

5.   The
registrant's other certifying  officer and I have disclosed, based on our most recent
evaluation of internal  control over financial reporting, to the registrant's auditors
and the audit  committee of the registrants board of directors (or persons
performing the  equivalent functions):

(a)   
All significant  deficiencies and  material weaknesses in the design or operation of
internal control over financial  reporting which are reasonably likely to  adversely
affect the registrant's ability to  record, process, summarize  and report financial
information;  and

(b)   
Any fraud, whether  or not  material, that involves management or other employees who
have a  significant role in the  registrant's internal control over financial  reporting.

Date:  March
27, 2007

/s/  Michael
D. DurhamName:  Michael D.  DurhamTitle:  President and Chief Executive
Officer