POWER OF ATTORNEY						Exhibit 24

	The undersigned hereby makes, constitutes and appoints each of Susan S.
Lindberg,
Robert N. Fitzgerald and William H. Gault, signing singly, as the undersigned's
true and lawful
attorney-in-fact, with full power and authority as hereinafter described on
behalf of and in the
name, place and stead of the undersigned to:

	(1)	prepare, execute, acknowledge in the undersigned's name and on the
undersigned's behalf, and submit to the U.S. Securities and Exchange Commission
(the "SEC") a
Form ID, including any amendments thereto, and any other documents necessary or
appropriate
to obtain codes and passwords enabling the undersigned to make electronic
filings with the SEC
of reports required by Section 16 of the Securities Exchange Act of 1934 and the
rules and
regulations promulgated thereunder, as amended from time to time (the "Exchange
Act"), or any
rule or regulation of the SEC;

	(2)	prepare, execute, acknowledge, deliver and file Forms 3, 4 and 5 or such
other
forms, including any amendments thereto, as may be required by Section 16 of the
Exchange Act
with respect to the securities of SemGroup Corporation, a Delaware corporation
(the
"Company"), with the SEC and the Company;

	(3)	seek or obtain, as the undersigned's representative and on the
undersigned's
behalf, information on transactions in the Company's securities from any third
party, including
brokers, employee benefit plan administrators and trustees, and the undersigned
hereby
authorizes any such person to release any such information to the undersigned
and approves and
ratifies any such release of information; and

	(4)	perform any and all other acts which in the discretion of such
attorney-in-fact are
determined to be necessary or desirable for and on behalf of the undersigned in
connection with
the foregoing.

The undersigned acknowledges that:

	(1)	this Power of Attorney authorizes, but does not require, each such
attorney-in-fact
to act in his or her discretion on information provided to such attorney-in-fact
without
independent verification of such information;

	(2)	any documents prepared and/or executed by each such attorney-in-fact on
behalf
of the undersigned pursuant to this Power of Attorney will be in such form and
will contain such
information and disclosure as such attorney-in-fact, in his or her discretion,
deems necessary or
desirable;

	(3)	neither the Company nor such attorneys-in-fact assume(s) (i) any liability
for the
undersigned's responsibility to comply with the requirements of the Exchange
Act, (ii) any
liability of the undersigned for any failure to comply with such requirements,
or (iii) any
obligation or liability of the undersigned for profit disgorgement under Section
16(b) of the
Exchange Act; and

	(4)	this Power of Attorney does not relieve the undersigned from responsibility
for
compliance with the undersigned's obligations under the Exchange Act, including
without
limitation the reporting requirements under Section 16 of the Exchange Act.

	The undersigned hereby gives and grants to each such attorney-in-fact full
power and
authority to do and perform all and every act and thing whatsoever requisite,
necessary or
appropriate to be done in and about the foregoing matters as fully to all
intents and purposes as
the undersigned might or could do if present, hereby ratifying all that such
attorney-in-fact of, for
and on behalf of the undersigned, shall lawfully do or cause to be done by
virtue of this Power of
Attorney.

	This Power of Attorney shall remain in full force and effect until revoked by
the
undersigned in a signed writing delivered to such attorneys-in-fact.

	IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of this 22nd day of June, 2017.

/s/ William J. McAdam
William J. McAdam


STATE OF OKLAHOMA	)
			) ss.
COUNTY OF TULSA		)

On this 22nd day of June, in the year 2017, before me, the undersigned, a Notary
Public in and
for said state, personally appeared William J. McAdam, personally known to me or
proved to me
on the basis of satisfactory evidence to be the person whose name is subscribed
to the within
instrument and acknowledged to me that he/she executed the same in his/her
capacity, and that
by his/her signature on the instrument, the person or the entity upon behalf of
which the person
acted, executed the instrument.

(SEAL)

						/s/ Elayna M. Conner
						Notary Public

						My Commission Expires: 2/22/2018