EXHIBIT 10.22

July 29, 2013

Dear Luis:

Ashland Inc. ("Ashland") considers the services you provide in your current role
leading the Ashland Water Technologies business unit (“AWT”), which is operated
by our wholly owned subsidiary Hercules Inc. (“Hercules”), to be essential to
AWT’s continuing operations. As Ashland evaluates strategic options for AWT,
including the potential for a change in ownership of AWT, whether through joint
venture, sale or other partial or complete divestiture (the “Transaction”),
Ashland would like to extend the following offer to you, in order to encourage
your continued employment during this period. Your acceptance of this offer (the
“Letter Agreement”) will rescind and replace any other written or verbal
agreements in place between you and Hercules and/or Ashland concerning your
continued employment with Hercules.

Subject to the conditions provided in this Letter Agreement, in the event you
remain employed through your Stay Date, as defined below, then Hercules will
provide you with a lump sum payment (“Retention Bonus”) equal to $400,000, less
applicable withholdings. Your Retention Bonus will be paid within 15 days of
your Stay Date.

For purposes of this Letter Agreement, your Stay Date shall be the earlier of:

i)
the date on which the potential Transaction closes;

ii)
the date on which a decision is made not to proceed with the potential
Transaction, and to continue to operate AWT under its current ownership;

iii)
the date your active employment is terminated by Hercules without cause; or

iv)
March 31, 2014.

During the term of this Letter Agreement, you will continue to receive
compensation at a rate at least equivalent to your level of base pay in effect
at the time this Letter Agreement was executed, and you will also continue to be
eligible to participate in those compensation and benefit programs offered to
regular, full-time employees of Hercules within your salary band.
 
You understand and agree that the Retention Bonus provided for under this Letter
Agreement will be made in accordance with any applicable requirements of
Internal Revenue Code §409A.

In the event your employment with Hercules terminates as a result of the
Transaction, then you may also be eligible for severance benefits from Hercules,
and nothing in this Letter Agreement will impair your right to receive such
benefits under any severance pay plan or program that would otherwise apply to
you.
    
You agree that you will keep the terms of this Letter Agreement completely
confidential, and that you will not hereafter disclose any information
concerning this agreement to anyone except your immediate family, financial
advisor and/or attorney; provided, that they agree in advance of said disclosure
to keep this information confidential and not disclose it to others.

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You further understand that this agreement will immediately terminate (an “Early
Termination”), and Hercules will be relieved of any obligation to provide the
Retention Bonus to you if any of the following occurs prior to your Stay Date:

i)
you voluntarily terminate your employment with Hercules;

ii)
you violate the confidentiality provisions contained herein;

iii)
Hercules terminates your employment for cause; For the purposes of this letter,
termination for cause will arise if you: (a) substantially fail to perform your
duties with Hercules, unless such failure is due to your incapacity as a result
of physical or mental illness; or (b) you engage in willful misconduct or gross
negligence in performing your duties;

iv)
in the event of your death. Provided, however, that Hercules will not be
relieved of any obligations under its employee benefits plans which arise due to
your death.

This Letter Agreement shall terminate on the earlier of your Stay Date or the
date on which an Early Termination occurs. Provided, however, that the
confidentiality provisions of this Letter Agreement and any obligations on the
part of Hercules or Ashland arising under this Letter Agreement during its term,
or triggered under this Letter Agreement on the date of its termination, shall
survive the termination of this Letter Agreement.

This Letter Agreement does not, in any way, constitute a contract or agreement
guaranteeing your continued employment. Hercules reserves the right to terminate
your employment at any time, with or without cause.

If you agree with the foregoing, please sign and date each original of this
Letter Agreement in the space provided for your signature, and return one
original to me prior to August 9, 2013. You may retain a copy for your records.

Should you have any questions, please feel free to contact me.

Sincerely yours,
                            
/s/ Susan B. Esler
Susan B. Esler
                            
Agreed to and accepted
this 29th day of July, 2013.

/s/ Luis Fernandez-Moreno
Luis Fernandez-Moreno

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