Exhibit 10.4
                                             Assignment and Assumption Agreement

                            ASSIGNMENT AND ASSUMPTION
                            -------------------------

     THIS ASSIGNMENT, ASSUMTION AND RELEASE AGREEMENT ("Agreement") is made and
entered into by and between Norit America Inc., having its principal place of
business at 5775 Peachtree Dunwoody Road, Suite C - 250, Atlanta, Georgia 30342
(hereinafter referred to as "Norit"), Earth Sciences, Inc. and its wholly-owned
subsidiary, ADA Environmental Solutions LLC, having their principal places of
business at 8100 South Park Way, Unit B, Littleton, Colorado 80120 (hereinafter
referred to as "ESI" and "ADA", respectively).

WHEREAS, Norit, ESI and ADA have entered into a Market Development Agreement
(the "MDA") and pursuant to the MDA have been collaborating to develop the
market for the use of powdered activated carbon for the reduction of mercury
emissions by North American coal-fired utilities and,

WHEREAS, ESI has authorized the spin-off of ADA to its shareholder (the
"Spin-Off") to create a separate company to pursue the development and marketing
of environmental technologies including activities under the MDA and

WHEREAS, ESI and ADA are desirous of ESI assigning to ADA and ADA assuming all
of ESI's rights and obligations under the MDA.

NOW, THEREFORE, in consideration of the premises, the mutual promises and
agreements contained herein, and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties hereto
agree as follows:

1. Assignment of ESI Rights to ADA: ESI, subject only to the distribution of
ADA-ES, Inc. stock to the shareholders of ESI, assigns to ADA all of its right,
title and interest in and to the MDA, and any technology, information and/or
intellectual property developed thereunder, to ADA. Such assignment is without
any limitation whatsoever.

2. Assumption by ADA: ADA agrees to assume all the rights and obligations of ESI
under the MDA, without limitation.

3. Norit Consent: Pursuant to the Terms and Conditions of MDS (paragraph 10),
Norit consents to this assignment and assumption.

4. ADA Indemnification: ADA agrees to indemnify and hold Norit harmless from all
claims, losses, costs and expenses that Norit may incur as a result of the above
assignment and assumption. This indemnification includes the payment of all
reasonable attorney's fees and out-of-pocket costs Norit may incur in enforcing
this indemnification against ADA.

5. Assignment and Assumption Subject to the Spin-Off: The assignment by ESI, the
assumption by ADA and the consent by Norit set forth above are all subject to
the consummation of the Spin-Off. If the Spin-Off does not occur, this Agreement
shall be null and void, and of no effect whatsoever.

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6. Applicable Law, Arbitration: The parties agree that the substantive laws of
the State of Georgia, to the exclusion of the laws of any other jurisdiction,
shall be applicable to this Agreement, its construction, interpretation, and
effect. Any controversy or claim arising out of or relating to this Agreement,
or its breach, or as to arbitrability, shall be settled by arbitration, using
one neutral arbitrator, in Atlanta, Georgia in accordance with the governing
rules of the American Arbitration Association. Judgment upon the award rendered
by the arbitrator may be entered in any court of competent jurisdiction.

7. Confidentiality, Non-Diversion, etc.: ESI agrees to continue to be bound by:
a) the mutual Confidentiality and Non-Disclosure Agreement between ESI, ADA and
Norit, dated on or about the date of the MDA, and any extensions thereto, and b)
paragraphs 2(d) and 2(l) and 14 and 16 of the Terms and Conditions of the MDA.
ESI further agrees not to do anything against Norit's interest that it could not
have otherwise done under the MDA.


Consented to:


    "Norit"                                 "ESI"
Norit America Inc.                          Earth Sciences, Inc.

By:___________________________              By:___________________________

Title:________________________              Title:_________________________

Date:_________________________              Date:_________________________


                                            "ADA"
                                            ADA Environmental Solutions, LLC

                                            By:___________________________

                                            Title:_________________________

                                            Date:_________________________


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