Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

¨ Rule 13d-1(b)
x Rule 13d-1(c)
¨ Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

x Rule 13d-1(b) only for Kinderhook Partners, LLC
¨ Rule 13d-1(c)
¨ Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

Item 1(a). Name of Issuer: Heritage-Crystal Clean, Inc.

Item 1(b). Address of Issuer’s Principal Executive Offices:

2175 Point Boulevard, Suite 375

Elgin, Il 60123

Item 2(b). Address of Principal Business Office or, if none, Residence:

(for all reporting persons)

2 Executive Drive, Suite 585

Fort Lee, New Jersey 07024

Item 2(d). Title of Class of Securities: Common Stock, par value $0.01

Item 2(e). CUSIP Number: 42726M106

Item 3. If this statement is filed pursuant to Rules 13d-1(b), or 13d-2(b) or (c), check whether the person filing is a:

If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution: _________________

Item 4. Ownership:

Provide the following information regarding the aggregate number and percentage of class of securities of the issuer identified in Item 1.

Ownership as of January 7, 2013 is incorporated herein by reference from items (5) – (9) and (11) of the cover pages of this Schedule 13G.

Item 5. Ownership of Five Percent or Less of a Class:

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than 5 percent of the class of securities, check the following [  ].

Item 6. Ownership of More than Five Percent on Behalf of Another Person:

Kinderhook Partners, LLC (the “Investment Adviser”) serves as the investment adviser to Kinderhook, LP (the “Partnership”) and is responsible for making investment decisions on the Partnership’s behalf. Kinderhook GP, LLC (the “General Partner”) serves as the general partner to the Partnership. Messrs. Tushar Shah and Stephen Clearman serve as the General Partner’s and Investment Adviser’s co-managing members and as a result, Mr. Clearman and Mr. Shah may be deemed to control such entities. Accordingly, Mr. Clearman and Mr. Shah may be deemed to have a beneficial interest in the shares of Common Stock by virtue of their indirect control of the Partnership’s, General Partner’s, and Investment Adviser’s power to vote and/or dispose of the shares of Common Stock. Mr. Clearman and Mr. Shah disclaim beneficial ownership of the shares of Common Stock except to the extent of their pecuniary interest, if any, therein.

Kinderhook, LP specifically disclaims beneficial ownership in the shares of Common Stock reported herein except to the extent of its pecuniary interest therein, if any.

Kinderhook GP, LLC specifically disclaims beneficial ownership in the shares of Common Stock reported herein except to the extent of its pecuniary interest therein, if any.

Kinderhook Partners, LLC specifically disclaims beneficial ownership in the shares of Common Stock reported herein except to the extent of its pecuniary interest therein, if any.

Item 7. Identification and Classification of the Subsidiary which Acquired the Security Being Reported on by the Parent Holding Company or Control Person:

Not Applicable

Item 8. Identification and Classification of Members of the Group:

Not Applicable

Item 9. Notice of Dissolution of Group:

Not Applicable

Item 10. Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

SIGNATURE

After reasonable inquiry and to the best of its knowledge and belief, I certify (the undersigned certifies) that the information set forth in this statement is true, complete and correct.

Item 10. Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

SIGNATURE

After reasonable inquiry and to the best of its knowledge and belief, I certify (the undersigned certifies) that the information set forth in this statement is true, complete and correct.