OMNI ENERGY SERVICES CORP. SECOND AMENDMENT AND WAIVER TO LOAN AGREEMENT

Exhibit 10.1

O MNI E NERGY S ERVICES C ORP .

S ECOND A MENDMENT AND W AIVER TO L OAN A GREEMENT

This Second Amendment and Waiver to Loan Agreement (the “Amendment” ) is entered into as of August 28, 2008, by and among O MNI E NERGY S ERVICES C ORP ., a Louisiana corporation (“ OMNI” ), each Subsidiary Borrower of OMNI party hereto (collectively, the “Subsidiary Borrowers” and OMNI and the Subsidiary Borrowers are collectively referred to as “ Borrowers ” and are each a “Borrower” ), the other Credit Parties signatory hereto, the Requisite Lenders signatory hereto, and Fifth Third Bank, an Ohio banking corporation, as Agent (the “Agent ).

P RELIMINARY S TATEMENTS

A. The Borrowers, the other Credit Parties party thereto, the Lenders party thereto and Fifth Third Bank, an Ohio banking corporation, as Agent are party to a certain Amended and Restated Loan and Security Agreement, dated as of April 23, 2008 (as previously amended, and it may be further amended, modified or supplemented from time to time, the “Loan Agreement” ). All capitalized terms used herein without definition shall have the same meanings herein as such terms have in the Loan Agreement.

B. The Borrowers, the other Credit Parties, the Requisite Lenders and Fifth Third Bank, as Agent, have agreed to amend the Loan Agreement, and waive certain provisions thereunder, pursuant to the terms and conditions set forth in this Amendment.

N OW , T HEREFORE , for good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, the parties hereto agree as follows:

S ECTION  1. W AIVERS .

The Borrowers have informed the Agent that:

(a) on or before December 31, 2008, OMNI may issue capital stock and receive cash proceeds as consideration therefore in an amount not to exceed $6,000,000 (any such amount received, the “Cash Equity Proceeds” );

(b) the following lien exists against the Headquarters Property (the “Existing Violation” ): a Junior Mortgage granted by OMNI in favor of Advantage Capital Partners V Limited Partnership, Advantage Capital Partners VI Limited Partnership, Advantage Capital Partners VII Limited Partnership, Advantage Capital Partners VIII Limited Partnership and Advantage Capital Partners XI Limited Partnership (formerly known as Advantage Capital Technology Fund, L.L.C.), dated August 17, 2000, and recorded with the Clerk of Court of Lafayette Parish, Louisiana on August 23, 2000, as File No. 00-032110 (the “Advantage Mortgage” ); and

(c) OMNI intends to sell the real property it owns in Abbeville, Vermilion Parish, Louisiana (the “Abbeville Sale” ).

The Borrowers have requested that the Agent (i) waive compliance with Section 2(d)(iv)(B) of the Loan Agreement solely with respect to the Cash Equity Proceeds that OMNI uses to purchase fractionation tanks, (ii) waive compliance with paragraph 7 of the Post-Closing Letter prior to the Second Amendment Effective Date (the “Delivery Violation” ), (iii) waive compliance with Section 13(d) of the Loan Agreement and paragraph 7 of the Post-Closing Letter solely with respect to the Abbeville Sale and the real property which is the subject thereof (the “Abbeville Violation” ), (iv) waive compliance with Section 13(c) of the Loan Agreement solely with respect to the Advantage Mortgage prior to the Second Amendment Effective Date (collectively with the Existing Violation, the Delivery Violation and the Abbeville Violation, the “Violations” ), and (iii) waive any Event of Default arising solely from the Violations.

Upon satisfaction of the conditions precedent set forth in Section 3 hereof (and with respect to the Abbeville Violation only, subject to the payment by OMNI to the Agent of the net cash proceeds from the Abbeville Sale for repayment of the Revolving Loans, the Lender and the Agent hereby waive the Violations and each and every Event of Default arising solely from the Violations. The Credit Parties acknowledge that the waivers under this Section 1 are specifically limited to the Violations and each and every Event of Default arising solely from the Violations. Except as specifically amended and waived hereby, all of the terms and conditions of the Loan Agreement shall stand and remain in full force and effect.

S ECTION  2. A MENDMENTS TO L OAN A GREEMENT AND P OST C LOSING L ETTER .

Upon satisfaction of the conditions precedent set forth in Section 3 hereof, the Loan Agreement and Post Closing Letter shall be and hereby are amended as follows:

Section 2.1. Amended Definitions. The definitions of “Capital Expenditures” , “ Commitment”, “Excess Availability”, “Maximum Loan Limit” and “Permitted Liens” set forth in Section 1 of the Loan Agreement are hereby amended and restated in their entirety to read as follows:

“Capital Expenditures” shall mean with respect to any period, the aggregate of all expenditures (whether paid in cash or accrued as liabilities and including expenditures for capitalized lease obligations) by Borrowers and their Subsidiaries during such period that are required by generally accepted accounting principles, consistently applied, to be included in or reflected by the property, plant and equipment or similar fixed asset accounts (or intangible accounts subject to amortization) (collectively, “Fixed Assets” ) on the balance sheet of Borrowers and their Subsidiaries, less the net cash proceeds of the Borrowers and their Subsidiaries received during such period from the sale of any Fixed Assets that are replaced with similar like-kind Fixed Assets within thirty (30) days of the date of such sale, net of reasonable

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direct costs and taxes paid as a direct result of such sale; provided that, notwithstanding the foregoing, Capital Expenditures shall not include expenditures of Cash Equity Proceeds, as defined in the Second Amendment, by the Borrowers for the purchase of fractionation tanks. (For purposes of clarity, in no event shall Eligible Inventory constitute Fixed Assets under this definition.)

“Commitment” shall mean, for purposes of this Agreement and of certain of the Subordination Agreements, any obligations of a lender to from time to time advance funds under this Agreement or an Other Agreement or to from time to time issue or provide assistance or other credit enhancements in connection with the issuance of a Letter of Credit or the making of a Swing Loan under this Agreement.

“Excess Availability” shall mean, as of any date of determination by Agent, the lesser of (i) the Maximum Revolving Loan Limit less the sum of the outstanding Revolving Loans, Swing Loans and Letter of Credit Obligations and (ii) the Revolving Loan Limit less the sum of the outstanding Revolving Loans, Swing Loans and Letter of Credit Obligations, in each case as of the close of business on such date and assuming, for purposes of calculation, that all accounts payable which remain unpaid more than sixty (60) days after the agreed upon due date between OMNI and the vendor, all taxes due and payable as of the close of business on such date are treated as additional Revolving Loans outstanding on such date.

“ Maximum Loan Limit ” shall mean Seventy-Five Million and No/100 Dollars ($75,000,000).

“Permitted Liens” shall mean (i) statutory liens of landlords, carriers, warehousemen, processors, mechanics, materialmen or suppliers incurred in the ordinary course of business and securing amounts not yet due or declared to be due by the claimant thereunder or amounts which are being contested in good faith and by appropriate proceedings and for which the applicable Credit Party has maintained adequate reserves; (ii) liens and security interests in favor of Agent; (iii) zoning restrictions and easements, licenses, covenants and other restrictions affecting the use of real property that do not individually or in the aggregate have a material adverse effect on a Credit Party’s ability to use such real property for its intended purpose in connection with such Credit Party’s business; (iv) liens in connection with purchase money indebtedness and capitalized leases otherwise permitted pursuant to this Agreement, provided, that such liens attach only to the assets

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the purchase of which was financed by such purchase money indebtedness or which is the subject of such capitalized leases; (v) liens and security interests in favor of a Subordinated Lender so long as such liens and security interests are fully subordinated pursuant to the applicable Subordination Agreement to the liens and security interests in favor of Agent; (vi) liens set forth on Schedule 1 hereto; (vii) liens specifically permitted by Agent in writing; (viii) involuntary liens securing amounts less than $100,000 and which are released or for which a bond acceptable to Agent in its Permitted Discretion has been posted within ten (10) days of its creation; (ix) the judgment lien against Trussco, Inc. in favor of Dunhill Resources Inc. for the amount of $15,708, as evidenced by the abstract of judgment filed in Lafayette Parish, Louisiana on November 15, 2005, but only to the extent that the holder of such judgment has not commenced the execution or enforcement of such judgment and (x) the Advantage Mortgage, as defined in the Second Amendment, to the extent it encumbers the Headquarters Property ( provided that the existence of such judgment as a Permitted Lien under this paragraph shall not prevent Agent from establishing reserves from time to time under this Agreement against the Revolving Loan Limit on account of such judgment).

Section 2.2. Amended Definition. The pricing grid in the definition of “Applicable Margin” in Section 1 of the Loan Agreement is hereby amended and restated in its entirety to read as follows:

Section 2.3. Additional Definitions. Section 1 of the Loan Agreement is hereby amended by interesting the following defined terms in their appropriate alphabetical locations:

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“Advantage Litigation” shall mean the lawsuit described in part 2 of Schedule 11(g) hereof and all related legal proceedings.

“Agent’s Quoted Rate” shall have the meaning specified in subsection 2(h)(ii) hereof.

“Second Amendment” shall mean that Second Amendment and Waiver to Loan Agreement dated as of August 28, 2008, by and among the Borrowers, the other Credit Parties signatory thereto and Fifth Third Bank, an Ohio banking corporation, as Lender and Agent.

“Second Amendment Effective Date” shall mean August      , 2008.

“Swing Line” shall mean, the credit facility for making Swing Loans described in subsection 2(h) hereof.

“Swing Loan” and “Swing Loans” shall each have the meaning specified in subsection 2(h)(i) hereof.

“Term A Loan Limit” means eighty percent (80%) of the net orderly liquidation value of the Equipment of the Credit Parties as expressed in the most recent machinery and equipment appraisals of such Equipment performed by an appraiser or appraisers selected by the Borrowers and acceptable to the Agent in its sole discretion; provided that, the aggregate net orderly liquidation value of such Equipment as expressed in such appraisals shall be reduced dollar for dollar by the net orderly liquidation value of any Equipment sold by a Credit Party after the date of the most recent appraisal of the Equipment owned by such Credit Party and shall be increased dollar for dollar by the purchase price of any Equipment acquired by a Credit Party after the most recent appraisal of the Equipment owned by such Credit Party.

Section 2.4. Revolving Loans. The first and second paragraphs of subsection 2(a) of the Loan Agreement are hereby amended and restated in their entirety to read as follows:

(a) Revolving Loans . Subject to the terms and conditions of this Agreement and the Other Agreements, each Lender, severally and not jointly, agrees to make its Pro Rata Share of revolving loans and advances (the “Revolving Loans” ) requested by each Borrower and approved by Agent in its Permitted Discretion, up to such Lender’s Revolving Loan Commitment so long as after giving effect to such Revolving Loans, the sum of the aggregate unpaid principal balance of the Revolving Loans, Swing Loans and

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the Letter of Credit Obligations does not exceed an amount up to the sum of the following sublimits (the “Revolving Loan Limit” ):

(i) up to eighty-five percent (85%) of the face amount (less maximum discounts, credits and allowances which may be taken by or granted to Account Debtors in connection therewith in the ordinary course of such Borrower’s business) of Borrowers’ Eligible Accounts; plus

(ii) up to the lesser of (x) fifty percent (50%) of the lower of cost or market value of Industrial Lift’s Eligible Inventory and (y) $1,000,000; plus

(iii) up to the lesser of (x) thirty percent (30%) of the lower of cost or market value of Borrowers’ Eligible Spare Parts Inventory and (y) $250,000; minus

(iv) Availability Reserve and such other reserves as Agent elects, in its Permitted Discretion, to establish from time to time;

provided , that the Revolving Loan Limit shall in no event exceed Twenty-Five Million and No/100 Dollars ($25,000,000) (such result being the “Maximum Revolving Loan Limit” ).

The aggregate unpaid principal balance of the Revolving Loans shall not at any time exceed the lesser of the (i) Revolving Loan Limit minus the sum of (x) the Letter of Credit Obligations and (y) the unpaid principal balance of the Swing Loans and (ii) the Maximum Revolving Loan Limit minus the sum of (x) the Letter of Credit Obligations and (y) the unpaid principal balance of the Swing Loans. If at any time the outstanding Revolving Loans exceed either the Revolving Loan Limit or the Maximum Revolving Loan Limit, in each case minus the sum of (x) the Letter of Credit Obligations and (y) the unpaid principal balance of the Swing Loans, Borrowers shall immediately, and without the necessity of demand by Agent, pay to Agent such amount as may be necessary to eliminate such excess and Agent shall apply such payment to the Revolving Loans and Swing Loans in such order as Agent shall determine in its sole discretion with any remaining balance to be held by Agent as security for the Letter of Credit Obligations; provided that Agent may, in its sole discretion, permit such excess (the “Interim Advance” ) to remain outstanding and continue to advance Revolving Loans to Borrowers on behalf of Lenders without the consent of any Lender for a period of up to thirty (30) calendar days, so long as (i) the amount of the Interim

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Advances does not exceed at any time Two Million and No/100 Dollars ($2,000,000), (ii) the aggregate outstanding principal balance of the Revolving Loans does not exceed the Maximum Revolving Loan Limit minus the sum of (x) the Letter of Credit Obligations and (y) the unpaid principal balance of the Swing Loans, and (iii) Agent has not been notified by Requisite Lenders to cease making such Revolving Loans. If the Interim Advance is not repaid in full within thirty (30) calendar days of the initial occurrence of the Interim Advance, no future advances may be made to Borrowers without the consent of all Lenders until the Interim Advance is repaid in full.

Section 2.5. Sale of Assets. Subsection 2(d)(iv)(A) of the Loan Agreement is hereby amended and restated in its entirety to read as follows:

(A) Sales of Assets . Upon receipt of the proceeds of the sale or other disposition of any real property, Equipment or Inventory exceeding $100,000 per item, or if any real property, Inventory or Equipment is damaged, destroyed or taken by condemnation in whole or in part, the proceeds thereof (net of the reasonable costs and fees incurred in a sale or other disposition) shall be paid by such Credit Parties to Agent, for the benefit of Agent and Lenders, as a mandatory prepayment of the Term A Loans, such payment to be applied against the remaining installments of principal in the inverse order of their maturities until such Term A Loans, are repaid in full, and then against the other Liabilities, as determined by Agent, in its sole discretion; provided that, notwithstanding the foregoing, the proceeds of the Abbeville Sale, as defined in the Second Amendment, net of the reasonable costs and fees incurred in the sale, shall be paid to the Agent, for the benefit of the Lenders, to be applied as a mandatory prepayment of the Revolving Loans. Notwithstanding the foregoing, with respect to all proceeds from sales or other dispositions of Equipment that do not exceed $500,000 in the aggregate in any Fiscal Year, Credit Parties shall deliver such proceeds to Agent and concurrently therewith deliver to Agent written notice and evidence detailing the nature of such proceeds, and upon receipt of such proceeds, Agent shall first apply such proceeds against the outstanding Revolving Loans until paid in full and then to the Swing Loans until paid in full and thereafter, if Borrowers do not replace such Equipment with similar Equipment having equal or greater market value (as determined by Agent) than the Equipment sold or otherwise d