EXHIBIT 99.1


                            EXPLANATION OF RESPONSES:

(1)  This Form 4 is being filed by (i) Portcullis Partners,  LP, a Texas limited
partnership ("Portcullis Partners"),  (ii) Portcullis G.P., LLC, a Texas limited
liability company  ("Portcullis GP"), and William V. Morgan, an individual ("Mr.
Morgan"  and  collectively  with  Portcullis  GP and  Portcullis  Partners,  the
"Reporting Persons").

On May 28, 2006, Richard D. Kinder (Mr. Kinder"), the Chairman of the Board and
Chief Executive Officer of Kinder Morgan, Inc. (the "Issuer"), together with GS
Capital Partners V Fund, L.P. ("Goldman"), AIG Global Asset Management Holdings
Corp. ("AIG"), Carlyle Partners IV, L.P. ("Carlyle"), and Carlyle/Riverstone
Energy Partners III, L.P. ("Carlyle/Riverstone" and, together with Goldman, AIG
and Carlyle, their respective affiliates, or investment funds managed by
Goldman, AIG, Carlyle and Carlyle/Riverstone, or their respective affiliates,
the "Sponsors") submitted to the Board of Directors of the Issuer a proposal
(the "Proposal") to acquire all of the outstanding common stock, par value $5.00
per share, of the Issuer ("KMI Common Stock"), other than certain shares of KMI
Common Stock held by Mr. Kinder, the Sponsors and certain other specified
persons participating in the Proposal, at a purchase price of $100 per share of
KMI Common Stock. The Reporting Persons are participants in the Proposal. As a
result of the Proposal, the Reporting Persons and the other persons
participating in the Proposal may be deemed to constitute a "group", within the
meaning of Section 13(d)(3) of the Securities Exchange Act of 1934, as amended
(the "Exchange Act"), that beneficially owns more than 10% of the outstanding
shares of the KMI Common Stock.

By reason of the provisions of Rule 16a-1 of the Exchange Act, the Reporting
Persons may be deemed to be the beneficial owners of any securities that may be
deemed to be beneficially owned by Mr. Kinder, the Sponsors and the other
persons participating in the Proposal. Each of the Reporting Persons disclaims
beneficial ownership of all shares of KMI Common Stock, except for the 916,000
shares of KMI Common Stock described in this Form 4. Except with respect to the
916,000 shares of KMI Common Stock described in this Form 4, this Form 4 shall
not be deemed an admission that any Reporting Person is a beneficial owner of
any shares of KMI Common Stock for purposes of Section 16 of the Exchange Act or
for any other purpose or that any Reporting Person has an obligation to file
this Form 4.