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Exhibit 10.1

FIRST AMENDMENT TO RESIN PURCHASE AGREEMENT

THIS FIRST AMENDMENT TO RESIN PURCHASE AGREEMENT (“First Amendment”) is made and
entered into as of the 17th day of August 2005, effective as of the 15th day of
July 2005 (the “Effective Date”), by and between AOC, LLC (“Seller”) and
INSITUFORM TECHNOLOGIES, INC. (“Buyer”).
 
Recitals of Fact

Seller and Buyer have entered into that certain Resin Purchase Agreement (the
“Agreement”), dated March 29, 2005, concerning the sale by Seller and the
purchase by Buyer of certain resins for use in Buyer’s manufacturing process.

The parties have agreed to modify the Agreement in certain respects, and the
parties desire to set forth such agreement in writing.

NOW, THEREFORE, for good and valuable considerations, the receipt and
sufficiency of which are hereby acknowledged, the parties hereby agree as
follows:
 
1.       As of the Effective Date, Section 2 of the Agreement is amended by
adding the following sentence to the end of Section 2.2:

Notwithstanding the foregoing, Seller agrees to sell and deliver, and Buyer
agrees to purchase and accept, during each Contract Year of the term hereof, for
internal consumption and not for resale, one hundred percent (100%) of Products
required by Buyer and Third Party Designees to fulfill commercial Insituform
product installation work in [REDACTED] (each, a “Committed Location”).
 
2.       As of the Effective Date, Section 6 of the Agreement is amended by
adding the following:
 
6.6    Freight to Committed Locations. Seller and Buyer agree that the freight
costs for the shipment of Products required by Buyer and Third Party Designees
to fulfill commercial Insituform product installation work at the Committed
Locations shall be calculated as follows:

 
a.
For the period from July 15, 2005 through July 14, 2006, the freight cost per
pound of Product to a Committed Location shall equal (A) the then Current
Freight Cost (as hereinafter defined) per pound of Product to such Committed
Location using Traditional Routing (as hereinafter defined) less (B) twenty-five
percent (25%) of the Freight Savings (as hereinafter defined).

 
b.
For the period from July 15, 2006 through July 14, 2007, the freight cost per
pound of Product to a Committed Location shall equal (A) the then Current
Freight Cost per pound of Product to such Committed Location using Traditional
Routing less (B) fifty percent (50%) of the Freight Savings.

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c.
For the period from July 15, 2007 through December 31, 2007, the freight cost
per pound of Product to a Committed Location shall equal (A) the then Current
Freight Cost per pound of Product to such Committed Location using Traditional
Routing less (B) seventy-five percent (75%) of the Freight Savings.

 
d.
If and in the event this Agreement remains in effect after December 31, 2007,
for the period from January 1, 2008 through July 14, 2008, the freight cost per
pound of Product to a Committed Location shall equal (A) the then Current
Freight Cost per pound of Product to such Committed Location using Traditional
Routing less (B) seventy-five percent (75%) of the Freight Savings. For periods
beginning on or after July 15, 2008, the freight cost per pound of Product to a
Committed Location shall equal the then Current Freight Cost per pound of
Product from the Seller’s Collierville, Tennessee facility to a respective
Committed Location (or from such other Seller facility that may be closer to the
Committed Location, whichever is less).

For purposes of this Section 6.6, Freight Savings shall mean and be equal to (A)
the then Current Freight Cost per pound of Product to a Committed Location from
Seller’s facility using Traditional Routing less (B) the then Current Freight
Cost per pound of Product to the same Committed Location from the Seller’s
Collierville, Tennessee facility; provided, however, in the event the Freight
Savings calculated in accordance with this sentence is an amount less than zero,
the Freight Savings shall be zero.

Current Freight Cost shall mean the then current freight cost per pound of
Product to ship the purchased Product from the Seller’s designated facility
using Traditional Routing or from Seller’s Collierville, Tennessee facility, as
the case may be, to the Committed Location, such freight cost as determined by
the most recent quarterly price quote received from Seller’s then current
carrier, said quote being updated each quarter.

Traditional Routing shall be defined as follows:

 
a.
For [REDACTED] the traditional route is from (1) Seller’s Lakeland, Florida
facility to (2) the respective Committed Location.

 
b.
For [REDACTED] the traditional route is from (1) Seller’s Collierville,
Tennessee facility to (2) Seller’s chill and fill subcontractor in Saint Louis,
Missouri to (3) [REDACTED].

 
3.
[REDACTED].

4.    Except as modified and amended hereby, the Agreement shall remain in full
force and effect.

5.    This First Amendment may be executed in a number of identical counterparts
which, taken together, shall constitute collectively one (1) agreement.

[SIGNATURE PAGE FOLLOWS]

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SIGNATURE PAGE
TO
FIRST AMENDMENT TO RESIN PURCHASE AGREEMENT

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IN WITNESS WHEREOF, the parties have caused this First Amendment to be executed
by their duly authorized representatives as of the day and year first above
written.

 
INSITUFORM TECHNOLOGIES, INC.
         
By:    /s/ David F. Morris                                                
 
Title:      Vice President                                                   
 
Name:    David F. Morris                                                
         
AOC, LLC
         
By:   /s/ John A. Roesle                                                  
 
Title:     Vice President                                                    
 
Name:   John A. Roesle