SecProbe.io

December 28, 2010
 David Emery Chief Executive Officer Black Hills Corporation 625 Ninth Street
Rapid City, South Dakota 57701

Re: Black Hills Corporation
Form 10-K for the Fiscal Year Ended December 31, 2009 Filed February 26, 2010 File No. 1-31303

Dear Mr. Emery:
We have reviewed your filing and have the following comments.  In some of our
comments, we may ask you to provide us with  information so we may better understand your
disclosure.
 Please respond to this letter within te n business days by providing the requested
information, or by advising us when you will provide the requested response.  If you do not believe our comments apply to your facts and circ umstances please tell us  why in your response.
 After reviewing the information you provide in response to these comments, we may
have additional comments.  Form 10-K for the Fiscal Year Ended December 31, 2009

 Items 1 and 2.  Business and Properties, page 10

 Oil and Gas Segment, page 34

 Summary Oil and Gas Reserve Data, page 35

 1. Item 1202(a)(7) of Regulation S-K states “Discl ose and describe the internal controls the
registrant uses in its reserves estimation effort .  In addition, disclose the qualifications of
the technical person primarily responsible fo r overseeing the preparation of the reserves
estimates and, if the registrant represents that a third party conducted a reserves audit, disclose the qualifications of  the technical person primarily  responsible for overseeing
such reserves audit.”  Please expand your discussion concerning internal controls and
describe the qualifications of the in -house technical person responsible for
overseeing/liaising with your third party engineer.

David Emery
Black Hills Corporation December 28, 2010 Page 2  Acreage, page 38

 2. We note the disclosure of 261 thousand net unde veloped acres (64% of the total) to your
ownership.  Please expand the presentation of  your undeveloped acreage to discuss the
near term expiration of any material unde veloped acreage as contemplated in Item
1208(b) of Regulation S-K.
 Items 7 and 7A.  Management's Discussion and An alysis of Financial Condition and Results of
Operations and Quantitative And Qualitative Disclosures About Market Risk, page 68
 Oil and Gas, page 88

 2. Please expand your discussion here to disclose  the information pertaining to your proved
undeveloped reserves as requi red by Item 1203 of Regulation S-K.  Note that changes
due to conversion to proved developed are required by 1203(b) as well as those due to
revisions, acquisition/dive stiture, drilling, and improved recovery.
 3. Please expand your discussion to include th e information pertaining to your product
delivery commitments, if any, as specified in  Item 1207 of Regulation S-K.  If you have
none, please so state.

Item 8.  Financial Statements and Supplementary Data, page 127

 Notes to Consolidated Financial Statements, page 136

 Note 1.  Business Description and Summary of  Significant Accounting Policies, page 136

 Legal Costs, page 142

4. We note that you record litigation settlem ent accruals net of probable insurance
recoveries.  Please tell us how you meet the ri ght of set-off criteria in ASC 210-20-45-1.
 Note 21.  Oil and Gas Reserves and Rela ted Financial Data (Unaudited), page 201

 5. We note that you do not disclose informa tion about management’s evaluation of
capitalized exploratory well costs.  Please tell us what consideration you gave to
providing the disclosures re quired by ASC 932-235-50-16.
 Standardized Measure of Discounted Future Net Cash Flows, page 205

 6. It appears you have included future revenue from the Newcastle Gas Processing Plant in
the future cash inflows of the standardized m easure.  Please tell us if these revenues are
derived solely from processing gas produc tion volumes in which you have a revenue
interest.  If they are not, explain your reasons for claimi ng such third party processing
revenues.  We may have further comment.

David Emery
Black Hills Corporation December 28, 2010 Page 3  7. Please tell us the portion of your proved liq uid reserves that are NGLs and the NGL
prices you used in proved reserve estimati on.  Explain the reason you did not disclose
NGL reserves separately from crude oil.
 8. We note the omission of the line item “Previ ously estimated development costs incurred
during the period” in the principal changes to the standardized measure as required by
FASB ASC subparagraph 932-10-65 -1.  Please revise your presentation to comply with
ASC 932.
 Exhibit 99

 9. We note the omission of items prescribed by Item 1202(a)(8) of Regul ation S-K.  Please
procure a third party reserv e report that includes:

 (i) The purpose for which the report was prepared and for whom it was prepared;
 (ii) The date on which the report was completed;
 (iv) Discussion of the sources of  production and pressure data;
 (v) Adjusted average product prices (after  application of differentials for quality,
transportation, etc.) including NGLs a nd discussion of COPAS charges;
 (vi) A discussion of the possibl e effects of regulati on on the ability of the registrant to
recover the estimated reserves;
 (viii) A statement that the third party ha s used all methods and procedures as it
considered necessary under the circum stances to prepare the report; and
 (x) The third party’s responsible technical person’s qualifications.
 We urge all persons who are responsible for th e accuracy and adequacy of the disclosure
in the filing to be certain that the filing include s the information the Securities Exchange Act of
1934 and all applicable Exchange Act rules requir e.  Since the company and its management are
in possession of all facts relating to a company’s disclosure, they are responsible for the accuracy
and adequacy of the disclosures they have made.
In responding to our comments, please provi de a written statement from the company
acknowledging that:
 the company is responsible for the adequacy an d accuracy of the disclo sure in the filing;

 staff comments or changes to disclosure in response to staff comments do not foreclose
the Commission from taking any action with respect to the filing; and

 the company may not assert staff comments as  a defense in any proceeding initiated by
the Commission or any person under the federal securities laws of the United States.

In addition, please be advise d that the Division of Enfo rcement has access to all
information you provide to the sta ff of the Division of Corporati on Finance in our review of your
filings or in response to our  comments on your filings.

David Emery
Black Hills Corporation December 28, 2010 Page 4

     You may contact Anthony Watson, Staff Accountant, at (202) 551-3318 if you have
questions regarding comments on the financial statem ents and related matters.   Please contact me
at (202) 551-3344 with a ny other questions.
          S i n c e r e l y ,
William Thompson
        A c c o u n t i n g  B r a n c h  C h i e f