--------------------------------------------------------------------------------

 
Exhibit 10.20     Eighteenth Amendment to Loan and Security Agreement between
Tengasco, Inc. as borrower and Prosperity Bank as Lender dated March 28, 2016

EIGHTEENTH AMENDMENT TO LOAN AND SECURITY AGREEMENT

This Eighteenth Amendment to Loan and Security Agreement (this “Amendment”) is
made and entered into as of March 28, 2016 (“Effective Date”), by and between
PROSPERITY BANK, a Texas state banking association, successor by merger to The
F&M Bank & Trust Company (“Lender”), acting as a lender on its own behalf, as
Agent under the Loan Agreement (as defined below), and as collateral agent on
behalf of CARGILL, INCORPORATED, a Delaware corporation (“Cargill”) as a Hedge
Provider, and TENGASCO, INC., a Delaware corporation (“Borrower”), TENNESSEE
LAND & MINERAL CORPORATION (“TLMC”), TENGASCO PIPELINE CORPORATION (“TPC”) and
MANUFACTURED METHANE CORPORATION (“MMC”) (each of TLMC, TPC, and MMC are a
“Guarantor” and collectively “Guarantors”) (collectively referred to herein as
the “Parties”).

RECITALS

A.          Borrower and Lender’s predecessor-in-interest, Citibank, N.A., a
national banking association formerly known as Citibank Texas, N.A., as Agent
and as a Bank (“Citibank”), (which was succeeded by Sovereign Bank (“Sovereign”)
and Lender) previously entered into that certain Loan and Security Agreement
dated effective June 29, 2006, (as assigned, assumed, amended, supplemented, or
restated to the date hereof, the “Loan Agreement”); whereby the Banks party to
the Credit Agreement agreed to extend a Line of Credit to Borrower equal to the
Commitment Amount, pursuant to the terms and conditions set forth in the Loan
Agreement (the “Loan”);

B.          To evidence the Loan, Borrower executed and delivered to Citibank
that certain Promissory Note dated June 29, 2006 (as amended and replaced the
“Note”), payable to the order of Citibank in the original principal sum of Fifty
Million and No/100 Dollars ($50,000,000), bearing interest and being payable as
therein provided, and such Note has been (i) assigned to Sovereign by that
certain Assignment of Note and Liens, dated as of December 17, 2007, by and
between Citibank (as assignor) and Sovereign (as assignee) and (ii) further
assigned to Lender by that certain Assignment of Note and Liens dated as of July
30, 2010, by and between Sovereign (as assignor) and Lender (as assignee); and

C.          The Parties now desire to further amend the Loan Agreement to
decrease the current Commitment Amount and Revolving Credit Borrowing Base and
to extend the Maturity Date, as herein set forth.

NOW, THEREFORE, for and in consideration of the mutual covenants and agreements
set forth herein, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Parties hereby agree as
follows:

--------------------------------------------------------------------------------

ARTICLE I
CAPITALIZED TERMS; DEFINITIONS

Section 1.01          Definitions.  Capitalized terms used in this Amendment, to
the extent not otherwise defined herein, shall have the same definitions
assigned to such terms in the Loan Agreement, as amended hereby. To the extent
applicable, the term “Lender” as used in this Amendment shall also refer to
Lender in its capacity as Agent and as a Bank under the Loan Agreement.

ARTICLE II
AMENDMENTS TO THE LOAN AGREEMENT

Section 2.01          Section 1.15 of the Loan Agreement (Commitment Amount). As
of the Effective Date, and subject to the conditions precedent required by the
provisions of Article III of this Amendment, Section 1.15 of the Loan Agreement
is deleted in its entirety and replaced with the following:

“1.15.     Commitment Amount shall mean, as of the Seventeenth
Amendment          Effective Date, Three Million One Hundred Eighty-Six Thousand
Dollars          ($3,186,000.00), or such other amount as agreed to in writing
by Borrower, Banks, and          Agent, but in no event in excess of the lesser
of (a) the Maximum Line of Credit Amount of (b) the Revolving Credit Borrowing
Base, as adjusted and redetermined from time to time pursuant to the provisions
of Article III.”

Section 2.02          Section 1.45.7 of the Loan Agreement (Eighteenth Amendment
Effective Date). As of the Effective Date, and subject to the conditions
precedent required by the provisions of Article III of this Amendment, Section
1.45.8 is added to the Loan Agreement to read as follows:

“1.45.8   Eighteenth Amendment Effective Date shall mean the Effective Date of
that certain Eighteenth Amendment to Loan and Security Agreement amending
the          Agreement.”

Section 2.03          Section 1.52 of the Loan Agreement (Maturity Date). As of
the Effective Date, and subject to the conditions precedent required by the
provisions of Article III of this Amendment, Section 1.52 of the Loan Agreement
is deleted in its entirety and replaced with the following:

“1.52      Maturity Date shall mean, unless a Note is sooner accelerated
pursuant to Section 10.2 hereof, January 30, 2018.”

Section 2.04          Section 3.1 of the Loan Agreement (Borrowing Base). As of
the Effective Date, and subject to the conditions precedent required by the
provisions of Article III of this Amendment, Section 3.1 of the Loan Agreement
is hereby amended by deleting the last sentence at the end of Section 3.1 and
replacing it with the following:

“Until further determination by Lender pursuant to the semiannual determinations
or otherwise pursuant to the terms hereof, Lender and Borrower agree and
stipulate that the Revolving Credit Borrowing Base as of the Eighteenth
Amendment Effective Date shall be $3,186,000.”

Section 2.05          Section 8.2 of the Loan Agreement (Leverage Ratio).  As of
the Effective Date and subject to the conditions precedent required by the
provisions of Article III of this Amendment, Section 8.2 of the Loan Agreement
is hereby deleted in its entirety and replaced with the following:

“8.2 Debt to Tangible Net Worth.  Borrower shall not permit the ratio of Debt to
Tangible Net Worth to exceed 1.0 to 1.0.  As used herein, ‘Tangible Net Worth’
shall mean Borrower’s total equity less intangible assets as of the last day of
each fiscal quarter of Borrower.”

--------------------------------------------------------------------------------

ARTICLE III
CONDITIONS PRECEDENT

Section 3.01          Conditions Precedent. When all of the following conditions
precedent have been fulfilled to the satisfaction of Lender, this Amendment
shall become effective:

(a)          The representations and warranties contained herein and in each of
the other Loan documents shall be true and correct as of the date hereof as if
made on the date hereof;

(b)          No Default or Event of Default shall have occurred and be
continuing;

(c)          Borrower and each Guarantor shall have executed and delivered this
Amendment and such other documents and agreements as Lender may reasonably
request;

(d)          All corporate proceedings taken in connection with the transactions
contemplated by this Amendment and all documents, instruments, and other legal
matters incident thereto shall be satisfactory to Lender and its legal counsel
in their sole discretion;

(e)          Lender shall have received such other documents, instruments, or
agreements as Lender shall reasonably request in connection with the execution
of this Amendment; and

(f)           Borrower shall pay the legal fees and expenses of Lender’s counsel
in connection with the preparation, negotiation, and execution of this
Amendment.

(g)          Lender shall have received a current Reserve Report covering the
Mortgage Properties and any other oil and gas properties owned by Borrower.

(h)          Borrower shall pay to Lender an extension fee of $10,000.00.

ARTICLE IV
WAIVER AND CONDITION SUBSEQUENT

Section 4.01          Waiver of Interest Coverage Ratio Default.  Borrower
failed to maintain the required Interest Coverage Ratio for the Applicable
Period ending December 31, 2015, and will fail to maintain such required
Interest Coverage Ratio for the Applicable Period ending March 30, 2016.  Lender
hereby waives the Events of Default resulting from such failure for the above
referenced Applicable Periods.  Lender hereby waives compliance with the
Interest Coverage Ratio covenant set forth in Section 8.3 of the Loan Agreement
for all future Applicable Periods through the Maturity Date.

Section 4.02          Condition Subsequent.  Not later than ninety (90) days
after the Effective Date of this Amendment, Borrower shall enter into Hedge
Transactions in good faith above break even.

ARTICLE V
RATIFICATIONS, REPRESENTATIONS, AND WARRANTIES

Section 5.01          Ratifications by Borrower. The terms and provisions set
forth in this Amendment shall modify and supersede all inconsistent terms and
provisions set forth in the Loan Agreement and, except as expressly modified and
superceded by this Amendment, the terms and provisions of the Loan Agreement are
ratified and confirmed and shall continue in full force and effect. The Loan
Agreement as amended by this Amendment shall continue to be legal, valid,
binding, and enforceable in accordance with its terms. Borrower acknowledges and
agrees that there are no claims or offsets against, or defenses or counterclaims
to, the terms and provisions of the Loan Agreement or any Note or the
indebtedness, obligations, and liabilities of Borrower to Lender or the liens
and security interests securing such indebtedness (including without limitation
any defenses or offsets resulting from or arising out of breach of contract or
duty, the amounts of interest charged, collected or received heretofore on any
Note or other indebtedness, or breach of any commitments or promises of any
type).

--------------------------------------------------------------------------------

Section 5.02          Renewal and Extension of Security Interests and Liens. 
Each of Borrower and Guarantors hereby renews, affirms, and ratifies all
security interests and liens created and granted by it to secure the
indebtedness, obligations and liabilities of Borrower and Guarantors to Lender.
Each of Borrower and Guarantors agrees that this Amendment shall in no manner
affect or impair the liens and security interests securing such indebtedness,
obligations, and liabilities, and that such liens and security interests shall
not in any manner be waived, the purposes of this Amendment begin to modify the
Loan Agreement as herein provided, and to carry forward all liens and security
interests securing the indebtedness, obligations and liabilities of Borrower and
Guarantors to Lender, which security interests and liens are acknowledged by
Borrower and Guarantors to be valid and subsisting. Further, Borrower and
Guarantors hereby covenant and agree that Lender may, without the signature of
Borrower, file UCC Financing Statements in any jurisdiction to perfect any
security interest now or hereafter granted to Lender.

Section 5.03          Representations and Warranties.  Borrower represents and
warrants to Lender as follows: (i) the execution, delivery, and performance of
this Amendment and any and all documents, agreements, and instruments executed
and/or delivered in connection herewith have been authorized by all requisite
corporate action on the part of Borrower and will not violate the Articles of
Incorporation or bylaws of Borrower or any agreement to which Borrower is a
party; (ii) the representations and warranties contained in the Loan Agreement
as amended hereby and in each of such other documents, agreements, and
instruments are true and correct on and as of the date hereof as though made on
and as of the date hereof; (iii) except as disclosed to Lender, no default or
Event of Default under the Loan Agreement has occurred and is continuing, and
(iv) except as disclosed to Lender, Borrower is in full compliance with all
covenants and agreements contained in the Loan Agreement, as amended hereby.

ARTICLE VI
MISCELLANEOUS

Section 6.01          Survival of Representations and Warranties.  All
representations and warranties made in the Loan Agreement or any other
documents, agreements, or instruments executed in connection therewith, shall
survive the execution and delivery of this Amendment, and no investigation by
Lender or any closing shall affect such representations and warranties or the
right of Lender to rely thereon.

Section 6.02          Reference to Loan Agreement.  Each of the Loan Documents
and the Loan Agreement and any and all other agreements, documents, or
instruments now or hereafter executed and delivered pursuant to the terms hereof
or pursuant to the terms of the Loan Agreement as amended hereby, are hereby
amended so that any reference in such documents, agreements, and instruments to
the Loan Agreement shall mean a reference to the Loan Agreement as amended
hereby.

Section 6.03          Severability.  Any provision of this Amendment held by a
court of competent jurisdiction to be invalid or unenforceable shall not impair
or invalidate the remainder of this Amendment and the effect thereof shall be
confined to the provision so held to be invalid or unenforceable.

Section 6.04          APPLICABLE LAW. THIS AMENDMENT SHALL BE DEEMED TO HAVE
BEEN MADE AND TO BE PERFORM ABLE IN AND SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF TEXAS.

Section 6.05          Successors and Assigns.  This Amendment is binding upon
and shall inure to the benefit of the Parties and their respective successors,
assigns, heirs, executors, and legal representatives, except that none of the
Parties other than Lender may assign or transfer any of its rights or
obligations hereunder without the prior written consent of Lender.

Section 6.06          Counterparts.  This Amendment may be executed in one or
more counterparts, each of which when so executed shall be deemed to be an
original, but all of which, when taken together, shall constitute one and the
same instrument.

Section 6.07          Effect of Waiver.  No consent or waiver, express or
implied, by Lender to or for any breach of or deviation from any covenant,
condition, or duty by Borrower, shall be deemed a consent to or waiver of any
other breach of the same or any other covenant, condition, or duty.

Section 6.08          Headings. The headings, captions, and arrangements used in
this Amendment are for convenience only and shall not affect the interpretation
of this Amendment.

--------------------------------------------------------------------------------

Section 6.09          Conflicting Provisions.  If any provision of the Loan
Agreement as amended hereby conflicts with any provision of any other Loan
Document, the provision in the Loan Agreement shall control.

Section 6.10          RELEASE. FOR AND IN CONSIDERATION OF THIS AMENDMENT AND
OTHER GOOD AND VALUABLE CONSIDERATION, THE RECEIPT AND SUFFICIENCY OF WHICH ARE
HEREBY ACKNOWLEDGED, BORROWER HEREBY VOLUNTARILY AND KNOWINGLY RELEASES AND
FOREVER DISCHARGES LENDER, ITS AGENTS, EMPLOYEES, SUCCESSORS, AND ASSIGNS, FROM
ALL POSSIBLE CLAIMS, DEMANDS, ACTIONS, CAUSES OF ACTION, DAMAGES, COSTS,
EXPENSES, AND LIABILITIES WHATSOEVER, KNOWN OR UNKNOWN, ANTICIPATED OR
UNANTICIPATED, SUSPECTED OR UNSUSPECTED, FIXED, CONTINGENT, OR CONDITIONAL, AT
LAW OR IN EQUITY, ORIGINATING IN WHOLE OR IN PART ON OR BEFORE THE DATE THIS
AMENDMENT IS EXECUTED, WHICH BORROWER MAY NOW OR HEREAFTER HAVE AGAINST LENDER,
ITS AGENTS, EMPLOYEES, SUCCESSORS AND ASSIGNS, IF ANY, AND IRRESPECTIVE OF
WHETHER ANY SUCH CLAIMS ARISE OUT OF (I) CONTRACT, TORT, VIOLATION OF LAW OR
REGULATIONS, OR OTHERWISE, (II) ANY LOAN, (III) ANY CONTRACTING FOR, CHARGING,
TAKING, RESERVING, COLLECTING, OR RECEIVING INTEREST IN EXCESS OF THE HIGHEST
LAWFUL RATE APPLICABLE, (IV) THE EXERCISE OF ANY RIGHTS AND REMEDIES UNDER THIS
AMENDMENT, THE LOAN AGREEMENT OR THE OTHER LOAN DOCUMENTS, OR (V) THE
NEGOTIATION, EXECUTION, OR DELIVERY OF THIS AMENDMENT, THE LOAN AGREEMENT, OR
ANY OTHER LOAN DOCUMENTS.

Section 6.11          ENTIRE AGREEMENT. THIS AMENDMENT, THE LOAN AGREEMENT AS
AMENDED HEREBY, AND ALL OTHER LOAN DOCUMENTS EXECUTED AND DELIVERED IN
CONNECTION WITH AND PURSUANT TO THIS AMENDMENT AND THE LOAN AGREEMENT, REPRESENT
THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE
OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE
ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.

Section 6.12          Legal Fees and Expenses. Notwithstanding anything
contained in the Loan Agreement, as amended, to the contrary, Borrower shall pay
all costs, fees, and expenses (including legal fees and expenses) incurred by
Lender arising out of or in connection with (i) the Loan Agreement, this
Amendment, and the Loan, (ii) the negotiation, preparation, execution, delivery,
and enforcement of the Loan Agreement, as amended, and (iii) the collection of
the Loan. Borrower hereby authorizes Lender to deduct from Borrower’s accounts
maintained with Lender, the amount of any costs, fees, and expenses owed by
Borrower when due.

[Signatures on following pages.]

--------------------------------------------------------------------------------

 
IN WITNESS WHEREOF, Borrower and Lender have caused this Amendment to be
executed as on the day and date first above written.

 
LENDER:
       
Prosperity Bank, successor by merger to The F&M Bank & Trust Company, in  its
capacity as Agent, as a Bank, and as Collateral Agent
             
By:
/s/ Alan Greenfield
   
     Alan Greenfield,
   
     Senior Vice President
             
BORROWER:
       
Tengasco, Inc., a Delaware corporation
             
By:
/s/ Michael J. Rugen
   
      Michael J. Rugen
   
      Chief Executive Officer

--------------------------------------------------------------------------------

Acknowledged and Accepted this 28th day
of March, 2016, by the following Loan Parties:

Tennessee Land & Mineral Corporation,
a Tennessee corporation

By: /s/ Michael J. Rugen
            Michael J. Rugen
            President

Tengasco Pipeline Corporation,
a Tennessee corporation

By: /s/ Michael J. Rugen
            Michael J. Rugen
            President

Manufactured Methane Corporation,
a Tennessee corporation

By: /s/ Michael J. Rugen
            Michael J. Rugen
            Vice-President
 
 

--------------------------------------------------------------------------------