Northern Natural Gas Company Northern Lights 2019 ... Postings/08...Northern Natural Gas Company...

Northern Natural Gas Company

Northern Lights 2019/Rochester Expansion Projects Docket No CP18-534-000

Response to Condition 5 Typical ROW Drawings

February 27, 2019

CO

NS

TR

UC

TIO

N R

.O

.W

.

CO

NS

TR

UC

TIO

N R

.O

.W

.

UNDISTURBED

SUBSOIL

SUBSOIL

50'-0"

WORKING SIDE

ORIGINAL GRADE

UNDISTURBED

SUBSOIL

12"

TOPSOIL

(MAXIMUM)

50'-0"

PROJECT PERMANENT R.O.W. WIDTH

25'-0"

EXISTING PERMANENT R.O.W. WIDTH

DITCH

SPOIL

STORAGE

TOPSOIL

STORAGE

AS APPLICABLE

25'-0"

TEMPORARY R.O.W. WIDTH

75'-0"

CONSTRUCTION RIGHT-OF-WAY

CP

IP

E S

TR

IN

G

25'-0"

SPOIL SIDE

CE

XIS

TIN

G 8

"

CP

RO

PO

SE

D 8

"

4'-0"

DEPTH OF COVER

(MIN.)

3'-0"

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND

REF DWG P3-1, P3-2, P3-3, P3-4, P3-5, P3-6, P3-10, P3-11, P3-12


Cre

scin

i, A

le

xa

nd

er

2/1

5/2

01

9 3

:4

8 P

MM

:\N

NG

2

01

9 N

L E

XP

AN

SIO

N P

RO

JE

CT

\8

_R

W C

ON

FIG

UR

AT

IO

N\A

LE

XA

ND

RIA

\R

OW

1

N

PROJECT NO.

FAC. CODE: REL. W.O.

DATEBY

DWG. NO.

CONST. YR

STATUS

PRELIM

BID

CONST.

SCALE:

DATE

CHECKED

BY

APPROVED

BY

FILE NO.:

ASBUILT

DESIGN

DRAWN

PL#

DATE

STA#

orthern

atural Gas

PROPOSED 8"

ALEXANDRIA BL LOOP EXTENSION

CONSTRUCTION R.O.W

SEC. 36, T129N, R30W

MORRISON COUNTY, MINNESOTA

01124367

ROW1

F

ON HOLD N/A

MNB72901

N/A

2019

RAC 3/8/18

AC 3/8/18

ROW1

NTS

NO.

REVISION - DESCRIPTION CHK'DDATE APP'DBY

F FILED WITH FERC AC 02/15/19 RAC GC

N/A

FILED WITH FERCANY CHANGES FROM WHAT ISSHOWN MUST BE IDENTIFIED

AND REVIEWED BYREGULATORY BEFORE

IMPLEMENTATION

APPROXIMATE LOCATIONS OF THE RIGHT-OF-WAY:

1. REF MP 0.0 - REF MP 13.3 (WEST LAY)

2. REF MP 13.4 - REF MP 13.55 (EAST LAY)


4. REF MP 14.0 - REF MP 14.52 (NORTHWEST LAY)


NOTE:

CONTRACTOR TO DISCUSS SOIL HANDLING AND STORAGE PLAN WITH

CLIENT PRIOR TO CONSTRUCTION. ANY ADDITIONAL WORKSPACE OR

CONCERNS RELATED TO CONSTRUCTION ROW SHALL BE ADDRESSED

PRE-CONSTRUCTION.

http://home.nngco.com/BRANCHLINE+Safety/Manuals/Vol+III/8700.asphttp://home.nngco.com/BRANCHLINE+Safety/Manuals/Vol+III/8700.asphttp://home.nngco.com/BRANCHLINE+Safety/Manuals/Vol+III/8700.asphttp://home.nngco.com/BRANCHLINE+Safety/Manuals/Vol+III/8700.asp

CO

NS

TR

UC

TIO

N R

.O

.W

.

CO

NS

TR

UC

TIO

N R

.O

.W

.

UNDISTURBED

SUBSOIL

SUBSOIL

50'-0"

WORKING SIDE

ORIGINAL GRADE

UNDISTURBED

SUBSOIL

12"

TOPSOIL

(MAXIMUM)

50'-0"


TOPSOIL

STORAGE

AS APPLICABLE

25'-0"


75'-0"


25'-0"

SPOIL SIDE

CP

RO

PO

SE

D 8"

DITCH

SPOIL

STORAGE

CP

IP

E S

TR

IN

G

4'-0"

DEPTH OF COVER

(MIN.)

3'-0"

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND

REF DWG P3-3, P3-6, P3-7, P3-8


Cre

scin

i, A

le

xa

nd

er

2/1

5/2

01

9 3

:4

8 P

MM

:\N

NG

2

01

9 N

L E

XP

AN

SIO

N P

RO

JE

CT

\8

_R

W C

ON

FIG

UR

AT

IO

N\A

LE

XA

ND

RIA

\R

OW

2

N

PROJECT NO.


DATEBY

DWG. NO.

CONST. YR

STATUS

PRELIM

BID

CONST.

SCALE:

DATE

CHECKED

BY

APPROVED

BY

FILE NO.:

ASBUILT

DESIGN

DRAWN

PL#

DATE

STA#

orthern

atural Gas

PROPOSED 8"

ALEXANDRIA BL LOOP EXTENSION

CONSTRUCTION R.O.W

SEC. 30, T140N, R32W

MORRISON COUNTY, MINNESOTA

01124367

ROW2

F

ON HOLD N/A

MNB72901

N/A

2019

RAC 3/8/18

AC 3/8/18

ROW2

NTS

NO.



N/A



IMPLEMENTATION




3. REF MP 15.2 - REF MP 16.1 (SOUTHEAST LAY)

NOTE:




PRE-CONSTRUCTION.


CO

NS

TR

UC

TIO

N R

.O

.W

.

CO

NS

TR

UC

TIO

N R

.O

.W

.

UNDISTURBED

SUBSOIL

SUBSOIL

50'-0"

WORKING SIDE

ORIGINAL GRADE

UNDISTURBED

SUBSOIL

12"

TOPSOIL

(MAXIMUM)

50'-0"


25'-0"


DITCH

SPOIL

STORAGE

TOPSOIL

STORAGE

AS APPLICABLE

25'-0"


75'-0"


EX

IS

TIN

G 3"

PR

OP

OS

ED

6"

PIP

E S

TR

IN

G

25'-0"

SPOIL SIDE

3'-0"

4'-0"

DEPTH OF COVER

(MIN.)

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND

REF DWG P3-1 TO P3-5


Wong, A

lice

2/15/2019 3:44 P

MM

:\N

NG

2019 N

L E

XP

AN

SIO

N P

RO

JE

CT

\8_R

W C

ON

FIG

UR

AT

IO

N\N

EW

P

RA

GU

E\R

OW

1

DATEBYSTATUS

PRELIM

BID

CONST.

DATE

CHECKED

BY

APPROVED

orthern

atural Gas

F

NO.



N/A




1. REF MP 0.0 - REF MP 0.1 (SOUTHWEST LAY)

2. REF MP 0.1 - REF MP 0.8 (NORTHEAST LAY)


NOTE:




PRE-CONSTRUCTION.

CO

NS

TR

UC

TIO

N R

.O

.W

.

CO

NS

TR

UC

TIO

N R

.O

.W

.

UNDISTURBED

SUBSOIL

SUBSOIL

50'-0"

WORKING SIDE

ORIGINAL GRADE

UNDISTURBED

SUBSOIL

12"

TOPSOIL

(MAXIMUM)

50'-0"


25'-0"


TOPSOIL

STORAGE

AS APPLICABLE

25'-0"


75'-0"


CE

XIS

TIN

G 3"

CP

RO

PO

SE

D 6"

CP

IP

E S

TR

IN

G

25'-0"

SPOIL SIDE

3'-0"

6'-0"

DEPTH OF COVER

(MIN.)

30'-0"

EXTRA TEMPORARY R.O.W. WIDTH

DITCH

SPOIL

STORAGE

DITCH

SPOIL

STORAGE

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND

REF DWG P3-3, P3-4


Me

rie

l, Je

ffre

y2

/2

0/2

01

9 1

1:2

4 A

MM

:\N

NG

2

01

9 N

L E

XP

AN

SIO

N P

RO

JE

CT

\8

_R

W C

ON

FIG

UR

AT

IO

N\N

EW

P

RA

GU

E\R

OW

2

N

PROJECT NO.


DATEBY

DWG. NO.

CONST. YR

STATUS

PRELIM

BID

CONST.

SCALE:

DATE

CHECKED

BY

APPROVED

BY

FILE NO.:

ASBUILT

DESIGN

DRAWN

PL#

DATE

STA#

orthern

atural Gas

PROPOSED 6"

NEW PRAGUE BRANCH LINE LOOP

CONSTRUCTION R.O.W

SEC. 5, T112N, R23W

LE SUEUR COUNTY, MINNESOTA

01124416

ROW2

F

ON HOLD N/A

MNB84501

N/A

2019

RAC 03/09/18

AC 03/09/18

ROW2

NTS

NO.



N/A



IMPLEMENTATION




NOTE:




PRE-CONSTRUCTION.

CO

NS

TR

UC

TIO

N R

.O

.W

.

CO

NS

TR

UC

TIO

N R

.O

.W

.

UNDISTURBED

SUBSOIL

SUBSOIL

50'-0"

WORKING SIDE

ORIGINAL GRADE

UNDISTURBED

SUBSOIL

12"

TOPSOIL

(MAXIMUM)

50'-0"


25'-0"


75'-0"


CE

XIS

TIN

G 3"

CP

RO

PO

SE

D 6"

25'-0"

SPOIL SIDE

25'-0"


3'-0"

6'-0"

DEPTH OF COVER

(MIN.)

TOPSOIL

STORAGE

AS APPLICABLE

CP

IP

E S

TR

IN

G

30'-0"


DITCH

SPOIL

STORAGE

15'-0"

DITCH

SPOIL

STORAGE

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND

REF DWG P3-3


Me

rie

l, Je

ffre

y2

/2

0/2

01

9 1

1:3

5 A

MM

:\N

NG

2

01

9 N

L E

XP

AN

SIO

N P

RO

JE

CT

\8

_R

W C

ON

FIG

UR

AT

IO

N\N

EW

P

RA

GU

E\R

OW

3

N

PROJECT NO.


DATEBY

DWG. NO.

CONST. YR

STATUS

PRELIM

BID

CONST.

SCALE:

DATE

CHECKED

BY

APPROVED

BY

FILE NO.:

ASBUILT

DESIGN

DRAWN

PL#

DATE

STA#

orthern

atural Gas

PROPOSED 6"

NEW PRAGUE BRANCH LINE LOOP

CONSTRUCTION R.O.W

SEC. 5, T112N, R23W

LE SUEUR COUNTY, MINNESOTA

01124416

ROW3

F

ON HOLD N/A

MNB84501

N/A

2019

RAC 03/09/18

AC 03/09/18

ROW3

NTS

NO.



N/A



IMPLEMENTATION



NOTE:




PRE-CONSTRUCTION.

CO

NS

TR

UC

TIO

N R

.O

.W

.

CO

NS

TR

UC

TIO

N R

.O

.W

.

CP

RO

PO

SE

D 16"

CP

IP

E S

TR

IN

G

SUBSOIL

60'-0"

WORKING SIDE

90'-0"


30'-0"

SPOIL SIDE

4'-0"

5'-0"

TEMPORARY

R.O.W WIDTH

35'-0"

TEMPORARY R.O.W WIDTH

50'-0"

PROJECT PERMANENT R.O.W WIDTH

4'-0"

DEPTH OF COVER

(MIN.)

DITCH

SPOIL

STORAGE

UNDISTURBED

SUBSOIL

TOPSOIL

STORAGE

AS APPLICABLE

UNDISTURBED

SUBSOIL

12"

TOPSOIL

(MAXIMUM)

ORIGINAL GRADE

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND

REF DWG P3-1 TO P3-13, P3-16 TO P3-33


Cre

scin

i, A

le

xa

nd

er

2/1

9/2

01

9 1

1:4

2 A

MM

:\N

NG

2

01

9 N

L E

XP

AN

SIO

N P

RO

JE

CT

\8

_R

W C

ON

FIG

UR

AT

IO

N\R

OC

HE

ST

ER

\R

OW

1

NO.


F FILED WITH FERC AC 02/19/19 TH GC

N

PROJECT NO.


DATEBY

DWG. NO.

CONST. YR

STATUS

PRELIM

BID

CONST.

SCALE:

DATE

CHECKED

BY

APPROVED

BY

FILE NO.:

ASBUILT

DESIGN

DRAWN

PL#

DATE

STA#

orthern

atural Gas

PROPOSED 16"

ROCHESTER GREENFIELD LATERAL

CONSTRUCTION R.O.W

SEC. 33, T105N, R15W

OLMSTED COUNTY, MINNESOTA

01120771

ROW1

F

ON HOLD N/A

MNB89701

N/A

2019

TH 03/08/18

AC 03/08/18

ROW1

AS SHOWN



IMPLEMENTATION


1. REF MP 0.0 - REF MP 1.4 (NORTH LAY)



4. REF MP 2.7 - REF MP 4.85 (SOUTH LAY)





CO

NS

TR

UC

TIO

N R

.O

.W

.

CO

NS

TR

UC

TIO

N R

.O

.W

.

CP

RO

PO

SE

D 16"

CP

IP

E S

TR

IN

G

SUBSOIL

50'-0"

WORKING SIDE

75'-0"


25'-0"

SPOIL SIDE

50'-0"


25'-0"

TEMPORARY

R.O.W WIDTH

12"

TOPSOIL

(MAXIMUM)

4'-0"4'-0"

4'-0"

DEPTH OF COVER

(MIN.)

UNDISTURBED

SUBSOIL

TOPSOIL

STORAGE

AS APPLICABLE

DITCH

SPOIL

STORAGE

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND

REF DWG P3-4, P3-5


Cre

scin

i, A

le

xa

nd

er

2/1

8/2

01

9 1

2:1

0 P

MM

:\N

NG

2

01

9 N

L E

XP

AN

SIO

N P

RO

JE

CT

\8

_R

W C

ON

FIG

UR

AT

IO

N\R

OC

HE

ST

ER

\R

OW

2

NO.



N

PROJECT NO.


DATEBY

DWG. NO.

CONST. YR

STATUS

PRELIM

BID

CONST.

SCALE:

DATE

CHECKED

BY

APPROVED

BY

FILE NO.:

ASBUILT

DESIGN

DRAWN

PL#

DATE

STA#

orthern

atural Gas

PROPOSED 16"


CONSTRUCTION R.O.W

SEC. 33, T105N, R15W


01120771

ROW2

F

ON HOLD N/A

MNB89701

N/A

2019

TH 03/08/18

AC 03/08/18

ROW2

AS SHOWN



IMPLEMENTATION




NOTE:




PRE-CONSTRUCTION.


CO

NS

TR

UC

TIO

N R

.O

.W

.

CO

NS

TR

UC

TIO

N R

.O

.W

.

CP

RO

PO

SE

D 16"

CP

IP

E S

TR

IN

G

SUBSOIL

60'-0"

WORKING SIDE

90'-0"


30'-0"

SPOIL SIDE

4'-0"

5'-0"

TEMPORARY

R.O.W WIDTH

35'-0"

TEMPORARY R.O.W WIDTH

50'-0"


DITCH

SPOIL

STORAGE

UNDISTURBED

SUBSOIL

TOPSOIL

STORAGE

AS APPLICABLE

UNDISTURBED

SUBSOIL

12"

TOPSOIL

(MAXIMUM)

ORIGINAL GRADE

30'-0"


6'-0"

DEPTH OF COVER

(MIN)

DITCH

SPOIL

STORAGE

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND



Me

rie

l, Je

ffre

y2

/2

0/2

01

9 1

1:2

8 A

MM

:\N

NG

2

01

9 N

L E

XP

AN

SIO

N P

RO

JE

CT

\8

_R

W C

ON

FIG

UR

AT

IO

N\R

OC

HE

ST

ER

\R

OW

3

NO.



N

PROJECT NO.


DATEBY

DWG. NO.

CONST. YR

STATUS

PRELIM

BID

CONST.

SCALE:

DATE

CHECKED

BY

APPROVED

BY

FILE NO.:

ASBUILT

DESIGN

DRAWN

PL#

DATE

STA#

orthern

atural Gas

PROPOSED 16"


CONSTRUCTION R.O.W

SEC. 15, T105N, R15W


01120771

ROW3

F

ON HOLD N/A

MNB89701

N/A

2019

TH 03/08/18

AC 03/08/18

ROW3

AS SHOWN



IMPLEMENTATION




CO

NS

TR

UC

TIO

N R

.O

.W

.

CO

NS

TR

UC

TIO

N R

.O

.W

.

UNDISTURBED

SUBSOIL

CP

RO

PO

SE

D 24"

CP

IP

E S

TR

IN

G

SUBSOIL

DITCH

SPOIL

STORAGE

65'-0"

WORKING SIDE

100'-0"


35'-0"

SPOIL SIDE

TOPSOIL

STORAGE

AS APPLICABLE

UNDISTURBED

SUBSOIL

12"

TOPSOIL

(MAXIMUM)

4'-0"

10'-0"

TEMPORARY

R.O.W WIDTH

ORIGINAL GRADE

40'-0"


50'-0"


4'-0"

DEPTH OF COVER

(MIN.)

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND

REF DWG P3-1 TO P3-4, P3-9, P3-12 TO P3-21, P3-23 TO P3-27


Cre

scin

i, A

le

xa

nd

er

2/1

9/2

01

9 1

0:2

9 A

MM

:\N

NG

2

01

9 N

L E

XP

AN

SIO

N P

RO

JE

CT

\8

_R

W C

ON

FIG

UR

AT

IO

N\R

OC

KF

OR

D\R

OW

1

NO.



N

PROJECT NO.


DATEBY

DWG. NO.

CONST. YR

STATUS

PRELIM

BID

CONST.

SCALE:

DATE

CHECKED

BY

APPROVED

BY

FILE NO.:

ASBUILT

DESIGN

DRAWN

PL#

DATE

STA#

orthern

atural Gas

PROPOSED 24"

ROCKFORD TO BUFFALO GREENFIELD LATERAL

CONSTRUCTION R.O.W

SEC. 31, T119N, R25W

HENNEPIN & WRIGHT COUNTY, MINNESOTA

01124336

ROW1

F

ON HOLD N/A

MNB89601

N/A

2019

RAC 03/08/18

AC 03/08/18

ROW1

AS SHOWN

N/A



IMPLEMENTATION














CO

NS

TR

UC

TIO

N R

.O

.W

.

CO

NS

TR

UC

TIO

N R

.O

.W

.

UNDISTURBED

SUBSOIL

CP

RO

PO

SE

D 2

4"

CP

IP

E S

TR

IN

G

SUBSOIL

DITCH

SPOIL

STORAGE

75'-0"

WORKING SIDE

100'-0"


25'-0"

SPOIL SIDE

TOPSOIL

STORAGE

AS APPLICABLE

UNDISTURBED

SUBSOIL

12"

TOPSOIL

(MAXIMUM)

4'-0"

50'-0"


ORIGINAL GRADE

50'-0"


4'-0"

DEPTH OF COVER

(MIN.)

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND

REF DWG P3-4 TO P3-8, P3-10 TO P3-12


Cre

scin

i, A

le

xa

nd

er

2/1

9/2

01

9 1

0:3

3 A

MM

:\N

NG

2

01

9 N

L E

XP

AN

SIO

N P

RO

JE

CT

\8

_R

W C

ON

FIG

UR

AT

IO

N\R

OC

KF

OR

D\R

OW

2

NO.



N

PROJECT NO.


DATEBY

DWG. NO.

CONST. YR

STATUS

PRELIM

BID

CONST.

SCALE:

DATE

CHECKED

BY

APPROVED

BY

FILE NO.:

ASBUILT

DESIGN

DRAWN

PL#

DATE

STA#

orthern

atural Gas

PROPOSED 24"


CONSTRUCTION R.O.W

SEC. 30, T119N, R25W


01124336

ROW2

F

ON HOLD N/A

MNB89601

N/A

2019

RAC 03/08/18

AC 03/08/18

ROW2

AS SHOWN

N/A



IMPLEMENTATION

APPROXIMATE LOCATIONS OF THE RIGHT- OF- WAY:




CO

NS

TR

UC

TIO

N R

.O

.W

.

CO

NS

TR

UC

TIO

N R

.O

.W

.

UNDISTURBED

SUBSOIL

CP

RO

PO

SE

D 24"

CP

IP

E S

TR

IN

G

SUBSOIL

DITCH

SPOIL

STORAGE

70'-0"

WORKING SIDE

100'-0"


30'-0"

SPOIL SIDE

TOPSOIL

STORAGE

AS APPLICABLE

UNDISTURBED

SUBSOIL

12"

TOPSOIL

(MAXIMUM)

5'-0"

TEMPORARY

R.O.W WIDTH

50'-0"


ORIGINAL GRADE

45'-0"


4'-0"

4'-0"

DEPTH OF COVER

(MIN.)

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND

REF DWG P3-1, P3-9 TO P3-10, P3-22, P3-23


Cre

scin

i, A

le

xa

nd

er

2/1

9/2

01

9 1

0:3

4 A

MM

:\N

NG

2

01

9 N

L E

XP

AN

SIO

N P

RO

JE

CT

\8

_R

W C

ON

FIG

UR

AT

IO

N\R

OC

KF

OR

D\R

OW

3

NO.



N

PROJECT NO.


DATEBY

DWG. NO.

CONST. YR

STATUS

PRELIM

BID

CONST.

SCALE:

DATE

CHECKED

BY

APPROVED

BY

FILE NO.:

ASBUILT

DESIGN

DRAWN

PL#

DATE

STA#

orthern

atural Gas

PROPOSED 24"


CONSTRUCTION R.O.W

SEC. 31, T119N, R25W


01124336

ROW3

F

ON HOLD N/A

MNB89601

N/A

2019

RAC 03/08/18

AC 03/08/18

ROW3

AS SHOWN

N/A



IMPLEMENTATION






CO

NS

TR

UC

TIO

N R

.O

.W

.

CO

NS

TR

UC

TIO

N R

.O

.W

.

UNDISTURBED

SUBSOIL

CP

RO

PO

SE

D 24"

CP

IP

E S

TR

IN

G

SUBSOIL

DITCH

SPOIL

STORAGE

40'-0"

WORKING SIDE

75'-0"


35'-0"

SPOIL SIDE

UNDISTURBED

SUBSOIL

12"

TOPSOIL

(MAXIMUM)

4'-0"

10'-0"

TEMPORARY

R.O.W WIDTH

50'-0"

PROJECT PERMANENT

R.O.W WIDTH

ORIGINAL GRADE

15'-0"


TOPSOIL

STORAGE

AS APPLICABLE

4'-0"

DEPTH OF COVER

(MIN.)

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND

REF DWG P3-12, P3-13, P3-15 TO P3-17


Cre

scin

i, A

le

xa

nd

er

2/1

9/2

01

9 1

0:3

4 A

MM

:\N

NG

2

01

9 N

L E

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_R

W C

ON

FIG

UR

AT

IO

N\R

OC

KF

OR

D\R

OW

4

NO.



N

PROJECT NO.


DATEBY

DWG. NO.

CONST. YR

STATUS

PRELIM

BID

CONST.

SCALE:

DATE

CHECKED

BY

APPROVED

BY

FILE NO.:

ASBUILT

DESIGN

DRAWN

PL#

DATE

STA#

orthern

atural Gas

PROPOSED 24"


CONSTRUCTION R.O.W

SEC. 14, T119N, R25W


01124336

ROW4

F

ON HOLD N/A

MNB89601

N/A

2019

RAC 03/08/18

AC 03/08/18

ROW2

AS SHOWN

N/A



IMPLEMENTATION







NOTE:




PRE-CONSTRUCTION.


CO

NS

TR

UC

TIO

N R

.O

.W

.

CO

NS

TR

UC

TIO

N R

.O

.W

.

UNDISTURBED

SUBSOIL

CP

RO

PO

SE

D 24"

CP

IP

E S

TR

IN

G

SUBSOIL

DITCH

SPOIL

STORAGE

65'-0"

WORKING SIDE

100'-0"


35'-0"

SPOIL SIDE

TOPSOIL

STORAGE

AS APPLICABLE

UNDISTURBED

SUBSOIL

12"

TOPSOIL

(MAXIMUM)

4'-0"

10'-0"

TEMPORARY

R.O.W WIDTH

50'-0"


ORIGINAL GRADE

40'-0"


4'-0"

DEPTH OF COVER

(MIN.)

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND

REF DWG P3-1, P3-4, P3-6


Wo

ng

, A

lice

2/1

5/2

01

9 3

:5

2 P

MM

:\N

NG

2

01

9 N

L E

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N P

RO

JE

CT

\8

_R

W C

ON

FIG

UR

AT

IO

N\W

IL

MA

R\R

OW

1

NO.





IMPLEMENTATION

N

PROJECT NO.


DATEBY

DWG. NO.

CONST. YR

STATUS

PRELIM

BID

CONST.

SCALE:

DATE

CHECKED

BY

APPROVED

BY

FILE NO.:

ASBUILT

DESIGN

DRAWN

PL#

DATE

STA#

orthern

atural Gas

PROPOSED 24"

WILMAR C-LINE EXTENSION

CONSTRUCTION R.O.W

SEC. 13, T115N, R25W

CARVER COUNTY, MINNESOTA

01124417

ROW1

F

ON HOLD N/A

MNB75601

N/A

2019

RAC 03/08/18

AC 03/08/18

ROW1

NTS

N/A






CO

NS

TR

UC

TIO

N R

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CO

NS

TR

UC

TIO

N R

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UNDISTURBED

SUBSOIL

CP

RO

PO

SE

D 24"

CP

IP

E S

TR

IN

G

SUBSOIL

DITCH

SPOIL

STORAGE

70'-0"

WORKING SIDE

100'-0"


30'-0"

SPOIL SIDE

TOPSOIL

STORAGE

AS APPLICABLE

UNDISTURBED

SUBSOIL

12"

TOPSOIL

(MAXIMUM)

10'-0"

TEMPORARY

R.O.W WIDTH

50'-0"


ORIGINAL GRADE

NORTH SOUTH

40'-0"


4'-0"

4'-0"

DEPTH OF COVER

(MIN.)

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND

REF DWG P3-2, P3-3


Wo

ng

, A

lice

2/1

5/2

01

9 3

:5

3 P

MM

:\N

NG

2

01

9 N

L E

XP

AN

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N P

RO

JE

CT

\8

_R

W C

ON

FIG

UR

AT

IO

N\W

IL

MA

R\R

OW

2

NO.





IMPLEMENTATION

N

PROJECT NO.


DATEBY

DWG. NO.

CONST. YR

STATUS

PRELIM

BID

CONST.

SCALE:

DATE

CHECKED

BY

APPROVED

BY

FILE NO.:

ASBUILT

DESIGN

DRAWN

PL#

DATE

STA#

orthern

atural Gas

PROPOSED 24"


CONSTRUCTION R.O.W

SEC. 23, T115N, R25W


01124417

ROW2

F

ON HOLD N/A

MNB75601

N/A

2019

RAC 03/08/18

AC 03/08/18

ROW2

NTS

N/A




CO

NS

TR

UC

TIO

N R

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.

CO

NS

TR

UC

TIO

N R

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.

UNDISTURBED

SUBSOIL

CP

RO

PO

SE

D 24"

CP

IP

E S

TR

IN

G

SUBSOIL

DITCH

SPOIL

STORAGE

65'-0"

WORKING SIDE

100'-0"


35'-0"

SPOIL SIDE

TOPSOIL

STORAGE

AS APPLICABLE

UNDISTURBED

SUBSOIL

12"

TOPSOIL

(MAXIMUM)

10'-0"

TEMPORARY

R.O.W WIDTH

25'-0"

PROJECT PERMANENT

R.O.W WIDTH

ORIGINAL GRADE

35'-0"

EXISTING PERMANENT R.O.W WIDTH

CE

XIS

TIN

G 12"

40'-0"


4'-0"

4'-0"

DEPTH OF COVER

(MIN.)

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND



Wo

ng

, A

lice

2/1

5/2

01

9 3

:5

4 P

MM

:\N

NG

2

01

9 N

L E

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AN

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N P

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CT

\8

_R

W C

ON

FIG

UR

AT

IO

N\W

IL

MA

R\R

OW

3

NO.





IMPLEMENTATION

N

PROJECT NO.


DATEBY

DWG. NO.

CONST. YR

STATUS

PRELIM

BID

CONST.

SCALE:

DATE

CHECKED

BY

APPROVED

BY

FILE NO.:

ASBUILT

DESIGN

DRAWN

PL#

DATE

STA#

orthern

atural Gas

PROPOSED 24"


CONSTRUCTION R.O.W

SEC. 14, T115N, R25W


01124417

ROW3

F

ON HOLD N/A

MNB75601

N/A

2019

RAC 03/08/18

AC 03/08/18

ROW3

NTS

N/A





CO

NS

TR

UC

TIO

N R

.O

.W

.

CO

NS

TR

UC

TIO

N R

.O

.W

.

UNDISTURBED

SUBSOIL

CP

RO

PO

SE

D 24"

CP

IP

E S

TR

IN

G

SUBSOIL

DITCH

SPOIL

STORAGE

40'-0"

WORKING SIDE

75'-0"


35'-0"

SPOIL SIDE

UNDISTURBED

SUBSOIL

12"

TOPSOIL

(MAXIMUM)

10'-0"

TEMPORARY

R.O.W WIDTH

50'-0"

PROJECT PERMANENT

R.O.W WIDTH

ORIGINAL GRADE

15'-0"


TOPSOIL

STORAGE

AS APPLICABLE

4'-0"

4'-0"

DEPTH OF COVER

(MIN.)

SCALE: 1/4" = 1'-0"

48" 24" 0 4'-0" 8'-0"

TOPSOIL

SUBSOIL

LEGEND

REF DWG P3-7


Wo

ng

, A

lice

2/1

5/2

01

9 3

:5

5 P

MM

:\N

NG

2

01

9 N

L E

XP

AN

SIO

N P

RO

JE

CT

\8

_R

W C

ON

FIG

UR

AT

IO

N\W

IL

MA

R\R

OW

4

NO.





IMPLEMENTATION

N

PROJECT NO.


DATEBY

DWG. NO.

CONST. YR

STATUS

PRELIM

BID

CONST.

SCALE:

DATE

CHECKED

BY

APPROVED

BY

FILE NO.:

ASBUILT

DESIGN

DRAWN

PL#

DATE

STA#

orthern

atural Gas

PROPOSED 24"


CONSTRUCTION R.O.W

SEC. 15, T115N, R25W


01124417

ROW4

F

ON HOLD N/A

MNB75601

N/A

2019

RAC 03/08/18

AC 03/08/18

ROW4

NTS

N/A



NOTE:




PRE-CONSTRUCTION.


Northern Natural Gas Company

Northern Lights 2019/Rochester Expansion Projects

Docket No CP18-534-000

Response to Conditions HDD Feasibility Studies

February 27, 2019

Document Number 193705887ED-RPT0001

Horizontal Directional Drill Feasibility Report Northern Natural Gas Company

Northern Lights 2019 Project - Alexandria Branch Line Loop Extension

Stantec Project: 193705887 Northern Natural Gas Project: 01124367

Rev. Date Desc By Checked Approved Client

0 18-Sep-2018 Issued for FERC TH RC GC

1 15-Feb-2019 Issued for FERC TH RC GC

HDD Feasibility Report

Project Identifier: 193705887 Document No: 193705887ED-RPT0001

Project Title: Northern Lights 2019 Project - Alexandria BL Loop Extension Revision: 1

ii

DISCLAIMER Stantec Consulting Ltd. has prepared this document for the sole use of Northern Natural Gas (Northern). The information within this document reflects Stantec’s best judgment on the data available at the time of preparation. Any third-party use of this information, dependence upon, or decisions made based on this information is the sole responsibility of such third-party. Stantec accepts no responsibility for loss or damages, if any, suffered by any third-party as a result of decisions made or actions based on the information contained herein.




iii

Table of Contents

1.0 PROJECT DESCRIPTION ............................................................................................. 1

2.0 PURPOSE AND SCOPE ................................................................................................ 1

3.0 DESIGN PARAMETERS ................................................................................................ 1

4.0 GEOTECHNICAL CONDITIONS .................................................................................... 3

5.0 CROSSING DESIGN SUMMARY .................................................................................. 3

6.0 INSTALLATION AND OPERATING STRESS (HDD ONLY) .......................................... 7

7.0 HYDRO-FRACTURE ASSESSMENT (HDD ONLY) ....................................................... 7

8.0 CONCLUSION & RECOMMENDATIONS .....................................................................11




1

1.0 Project Description Northern Natural Gas Company (Northern) proposes to construct and operate a 4.3-mile extension of the existing Alexandria branch line loop (MNB72902). The proposed loop extension will generally parallel the existing 8-inch-diameter MNB72901 Alexandria branch line. The loop extension will be constructed as two segments. The Project will consist of construction of: (1) approximately 1.0 mile of 8-inch-diameter pipeline extension beginning at milepost (MP) 12.50 of the MNB72901 branch line and extending to the termination point just east of the Mississippi River, and (2) approximately 3.3 miles of 8-inch-diameter pipeline extension beginning on the west side of the Mississippi River and extending to where it will tie into the 8-inch-diameter MNB72901 branch line near MP 16.81, immediately west of 100th Avenue, Morrison County, Minnesota. Northern plans to construct the Project in accordance with Section 7 of the Natural Gas Act, as amended, and Part 157 of the Federal Energy Regulatory Commission’s Regulations. The planned activities described above are herein referred to as the Alexandria branch line loop extension (Project).

2.0 Purpose and Scope A total of 11 horizontal directional drills (HDD) crossings are proposed for the Project. Nine HDDs were designed as site-specific crossings. This report summarizes the feasibility of the HDD design, addressing anticipated installation loads, installation and operating stresses, comparison of modelled formation limiting pressure vs drilling annular pressure, and potential mitigation measures for these nine crossings.

The remaining two HDDs are proposed as typical HDD. These typical HDDs cross roads, have shorter lengths (200-660 feet), and are generally completed within one week. The typical HDDs are considered feasible and are not discussed further. The road-crossing HDDs have a typical profile, which is depicted in drawing ABL-TYP-01.

Not all utility locations and depths were verified at the time of this report. Once all utilities are verified, the bore profiles, entry/exit locations and workspaces may require modification.

3.0 Design Parameters The design methodology is in accordance with the following standards and guidelines:

- DOT Regulations 49 CFR Part 192

- ASME B31.8 (2016)

- “Installation of Pipelines by Horizontal Directional Drilling – An Engineering Design Guide” PRCI PR-227-9424 (2008)




2

- “Pipeline Design for Installation by Horizontal Directional Drilling” ASCE MOP 108 (2014)

General crossing design parameters are provided in Table 1 below.

Table 1 – Crossing Design Parameters

Parameter Unit Alexandria

Service Natural Gas

Maximum Allowable Operating Pressure psi 1050

Maximum Design Temperature °F 100

HDD Restraint Temperature °F 40

Pipe OD in 8.625

Pipe WT in 0.25

Pipe Grade ksi X42

Density of Drilling Mud ppg 9.5

Coefficient of Friction (Pipe to Soil) 0.3

Coefficient of Friction (Pipe to Rollers) 0.1

Coefficient of Fluidic Drag psi 0.025

Ground profiles are based on civil survey data.




3

4.0 Geotechnical Conditions Based on preliminary crossing profiles, a geotechnical investigation consisting of 13 soil borings was planned. The results of the geotechnical field and laboratory programs are provided in “Geotechnical Data Report – Northern Lights 2019 Expansion-Alexandria Loop, Little Falls, Minnesota,” Terracon Consultants, April 11, 2018 (Project MP185036A).

The borings generally encountered topsoil underlain by sandy lean clays; however, some layers of poorly graded sand also were encountered within the clays. One instance of a poorly graded gravel layer was seen in the most eastern bore.

Groundwater was observed at varying depths at the times the borings were performed and, where observed, was likely perched within water-bearing soils bound by clay layers. The soil borings were not left open long enough for hydrostatic groundwater levels to equilibrate and additional testing or observations would be required to evaluate long term groundwater levels. Seasonal and annual fluctuations of groundwater should also be anticipated.

Subsurface conditions are briefly summarized in Table 2 below, focusing on qualitative features relevant to the feasibility of HDD construction. Evaluation of formation-limiting pressure is based on simplified stratigraphies and what are considered to be conservative parameters for the soil properties for characteristic soils. See section 7 below.

5.0 Crossing Design Summary Summaries of each crossing design and bore profile are provided in Table 2 below.




4

Table 2 – Crossing Design and Bore Profile Summaries

Crossing Identification

(Drawing Number)

Approximate Crossing

Distance (ft)

Features Avoided

by Crossing

Notes on Crossing

Alignment, Profile and Workspace

Notes on Drilling/ Boring and Pullback Operations

Unfactored Pull Force & Anticipated

Drill Rig Size (for site layout and drill

parameter assumptions)

Relevant Soil Borings & Notes on Geotechnical

Conditions

ABL-P4-1 (HDD) 388 Wetland

Alignment is straight and workspace is considered adequate.

One pullback section is expected.

Without Buoyancy Control: 6,143 lbs Assumed Rig Size: 100, 000 lbs

Boring Log No.13 The principal strata encountered were poorly graded sand and sandy lean clay. A 5ft layer of poorly graded gravel was also encountered. The area is small and is not expected to lead to issues regarding drillability.

ABL-P4-2 (HDD) 1,265

123rd St and Wetland



Without Buoyancy Control: 18,046 lbs Assumed Rig Size: 100,000 lbs

Boring Log No.11/No.12 The principal strata encountered were sandy lean clay, poorly graded sand, and clayey sand.

ABL-P4-3 (HDD) 564

Driveway on private property




Boring Log No.10 The principal strata encountered were poorly graded sand and sandy lean clay.




5


(Drawing Number)


Distance (ft)

Features Avoided

by Crossing

Notes on Crossing







Conditions

ABL-P4-4 (HDD) 828

Great River Road and wooded lot




Boring Log No.9 The principal strata encountered were poorly graded sand and clayey sand.

ABL-P4-5 (HDD) 768

125th St and Pike Hills Drive




Boring Log No.8 The principal strata encountered were poorly graded sand and silty sand.

ABL-P4-8 (HDD) 1,878 Wetland

Alignment is straight and workspace is considered adequate



Boring Log No.6/No.7 The principal strata encountered were sandy lean clay and poorly graded sand.

ABL-TYP-01 (TYPICAL

HDD) 127 130th St This is considered a typical crossing.

ABL-P4-10 (HDD) 1,056 Wetlands




Boring Log No.5/No.6 The principal strata encountered were sandy lean clay, clayey sand, and poorly graded sand.




6


(Drawing Number)


Distance (ft)

Features Avoided

by Crossing

Notes on Crossing







Conditions

ABL-P4-11 (HDD) 4,610

Wetlands and private driveway


Four pullback sections are expected.


Boring Log No.3/No.4/No.5 The principal strata encountered were sandy lean clay, lean clay, silty sand, clayey sand, and poorly graded sand.

ABL-P4-12 (HDD) 1,684 Wetlands

Alignment is slightly curved and workspace is considered adequate

Two pullback sections are expected.


Boring Log No.1/No.2 The principal strata encountered were sandy lean clay, clayey sand and poorly graded gravel with silty clay and sand.

ABL-TYP-01 (TYPICAL

HDD) 180 100th Ave This is considered a typical crossing.




7

6.0 Installation and Operating Stress (HDD only) Installation and operating stresses were evaluated for the drills, based on the proposed bore profile. All acceptability requirements for stress, per ASME B31.8 and PRCI PR-227-9424, are satisfied.

Table 3 below provides the maximum installation and operating stresses.

Table 2 – Maximum Installation and Operating Stress

Crossing Maximum Installation Stress (Unity Check based on API

allowable – See Notes 1 & 2)

Maximum Operating Stress (Unity Check based on PRCI shear

stress allowable of 45% SMYS)

ABL-P4-1 0.45 0.98

ABL-P4-2 0.52 0.98

ABL-P4-3 0.46 0.98

ABL-P4-4 0.48 0.98

ABL-P4-5 0.48 0.98

ABL-P4-8 0.56 0.98

ABL-P4-10 0.50 0.98

ABL-P4-11 0.79 0.98

ABL-P4-12 0.58 0.98 Notes:

1. A tensile stress limit of 60% of SMYS (Specified Minimum Yield Strength) (based on API RP 2A-WSD R2014) is used instead of 90% of SMYS (as per PRCI PR-227-9424 2008.)

2. The maximum recommended pull force for the NPS 8 pipe specification is 150,000 lbs. In the case of the product pipe being stuck during pullback, more detailed evaluation may be required to determine limits for maximum pull force, maximum hammering loads and hammering duration.

7.0 Hydro-fracture Assessment (HDD only) Hydro-fracture assessments are based on comparing the modelled maximum formation limiting pressure with the minimum drilling fluid annular pressure.

The maximum formation limiting pressure was modelled based on industry accepted cavity expansion, “Delft,” method. Soils were treated as:




8

- Purely cohesive with undrained shear strength based on correlations of SPT-N values with unconfined compressive strength. The correlated unconfined compressive strength is divided by two for the corresponding shear strength.

The minimum total annular pressure consists of components for static head and frictional losses in the bore. Parameters for the pilot bore diameter and drill rod size were assumed based on expected drill rig sizes. Parameters for drilling fluid density, viscosity and yield point were assumed based on typical values.

Table 4 below provides a summary of the hydro-fracture assessment, including the minimum factor of safety within the central length of the drill and potential mitigation options. Table 4 – Summary of Hydro-Fracture Assessment

Crossing Minimum Factor of Safety

(Formation Limiting Pressure / Total Annular Pressure)

Issues and Mitigation Options (See Note 1)

ABL-P4-1

4.60 (in the middle of the drill alignment) 1.27 (farmland 40 ft before the exit, 60 ft outside of the wetland buffer.)

As modelled, there is a risk of inadvertent returns in the last 50 ft on the exit (west) side. Only one geotechnical borehole was drilled, and it is near the entry (east) side. The annular pressure model assumes that the poorly graded sand at the exit is loose like it is at the entry.

ABL-P4-2 2.17 (outside the wetland around 689+60) As modelled, there is a risk of inadvertent returns in the last 80 ft on the exit (east) side.

ABL-P4-3 2.93 (far from driveway around 706+87) As modelled, there is a risk of inadvertent returns in the last 30 ft on the exit (west) side.

ABL-P4-4 6.32 (around 720+05)

This drill is up a hill. The elevation gain between the exit point and the bottom of the drill is 55 ft. For the last 50 ft of this drill, cuttings are returned primarily by gravity, rather than drilling fluid pressure. Fluid management should account for anticipated flows due to drilling up the hill. Only one geotechnical borehole was drilled, and it is near the entry (east) side. The annular pressure model assumes the soil information at the top of the hill.

ABL-P4-5 3.22 (95 ft from the exit)

This drill is up a hill. The elevation gain between the exit point and the bottom of the drill is 46 ft. For the last 150 ft of this drill, cuttings are returned primarily by gravity, rather than drilling fluid pressure. Fluid management should account for anticipated flows due to drilling up the hill.




9




Only one geotechnical borehole was drilled, and it is near the entry (east) side. The annular pressure model assumes the soil information at the top of the hill.

ABL-P4-8

2.40 (in the middle of the drill alignment) 1.23 (50 ft before the road, around 771+50)

As modelled, there is a high risk of inadvertent returns in the last 290 ft on the exit (east) side. Road is located at the edge of the high risk area. Mitigation may include partially tripping the drill pipe to clean/condition the bore prior to drilling the last 330 ft of the drill at reduced pressures. A relief well could be drilled near the road to alleviate the risk of a release damaging the road. Geotechnical boreholes used to facilitate this design did not reach the required depth for this HDD. Deeper soil borings required for more accurate information on the soil conditions.

ABL-P4-10

3.06 (in the middle of the drill alignment) 1.28 (inside the wetland around 800+91)

As modelled, there is a risk of inadvertent returns in the last 70 ft on the exit (west) side. Mitigation may include partially tripping the drill pipe to clean/condition the bore prior to drilling the last 120 ft of the drill at reduced pressures.

ABL-P4-11 1.49 (2156 ft before the exit around 831+84, start of medium risk area)

As modelled, there is a high risk of inadvertent returns in the last 1150 ft on the exit (west) side, which is within the wetland. Mitigation may include drilling from both the entry side and the exit side and intersecting in the middle. As half the drill has a medium to high risk of inadvertent returns, and there are wetlands throughout.

ABL-P4-12

1.86 (in the middle of the drill alignment) 1.37 (260 ft from the exit)

As modelled, there is a high risk of inadvertent returns in the last 200 ft on the exit (east) side. Mitigation may include partially tripping the drill pipe to clean/condition the bore prior to drilling the last 300 ft of the drill at reduced pressures.

Notes: 1. General mitigation measures include: - Deeper entry/exit pits. - Manage drilling fluids by maintaining drilling fluid density and sand content, and

balancing flow rates and drilling speed.




10




- Adjust fluid composition with changing soil conditions, considering the use of additives for lost circulation, viscosifiers, flocculants or coagulants.

- Reduce pumping for the last portion of the pilot drill, relying on tripping of the drill rod and minimal mud circulation to clean the pilot hole.

- Use conductor casing to stabilize the borehole for a portion of the straight tangent of the bore profile at the entry and/or exit. Conductor casing shall be sized based on the final reaming pass.

Factors of safety greater than 1.5 are considered to have a low risk for inadvertent returns with a competent standard of care. Factors of safety between 1.25 and 1.5 are considered to be medium risk, but manageable with attention to matching drilling production with fluid management. Factors of safety less than 1.25 are considered to be high risk and suggest re-evaluation of the bore profile but are still manageable by an experienced HDD Contractor with appropriate mitigation measures.

The minimum total annular pressure is based on assumed drilling parameters and should be re-evaluated based on the HDD Contractor’s execution plan.




11

8.0 Conclusion & Recommendations All of the proposed crossings in the Project are considered feasible:

- Based on the subsurface investigation, the HDD bore profiles are expected to be drilled through formations that are suitable for HDD. The only area of concern is with drill P4-1, which involves bending through 5 ft of poorly graded gravel. P4-5 and P4-8 have been modified since the original soil borings were proposed. As such additional/deeper soil borings would be required to more accurately determine the formations that would likely be encountered during drilling.

- The crossings are considered to be feasible in terms of surface constraints and workspace for operations at the entry/exit locations and pullback section.

- The specified HDD crossing pipe satisfies acceptability requirements for installation and operating stresses.

- As modelled, the hydro-fracture assessments indicate the crossings have low to medium risk of inadvertent returns within the central length of the drills and high risk of inadvertent returns towards the exit. Despite these risks, the crossings are considered to be feasible, and mitigation measures have been suggested to address the risks. The suggested mitigation measures are proven and within the capabilities of experienced HDD contractors. P4-11 has a medium to high risk of inadvertent returns throughout the second half of the drill so an intersect method is recommended.

General recommendations for the operator in preparation for construction include:

1. Allowing adequate time for regulatory and permitting requirements;

2. Ensuring that HDD Contractor execution plans reflect practical implementations of the HDD design, and re-evaluation of hydro-fracture assessments based on the HDD Contractor’s execution and fluid management plans;

3. Ensuring clear understanding of the roles of the Pipeline Contractor, HDD Contractor, Environmental inspector, HDD construction inspector and other Company representatives with respect to safety and mitigation/response plans.



Northern Lights 2019 Project - New Prague Branch Line Loop



1 15-Feb-2019 IFR TH RC GC



Project Title: Northern Lights 2019 Project - New Prague Branch Line Loop Revision: 1





Table of Contents






6.0 INSTALLATION AND OPERATING STRESS (HDD ONLY) .......................................... 8

7.0 HYDRO-FRACTURE ASSESSMENT (HDD ONLY) ....................................................... 8





1.0 Project Description Northern Natural Gas Company (Northern) proposes to construct and operate an approximately 1.6 mile, 6-inch-diameter pipeline loop MNB84501 paralleling the existing MNB84501 3-inch-diameter New Prague branch line. The proposed loop will take-off from the existing 4-inch-diameter MNB84401 Belle Plaine branch line at a point in Section 5, T112N, R23W, Le Sueur County, Minnesota. The downstream tie-in will be located at Northern’s existing New Prague MN #1 TBS in Section 4, T112N, R23W, Le Sueur County, Minnesota, where the new loop will tie into the existing New Prague branch line. Northern plans to construct the Project in accordance with the section 7 of the Natural Gas Act, as amended, and Part 157 of the Federal Energy Regulatory Commission’s Regulations. The planned activities described above are herein referred to as the New Prague Branch Line Loop (Project).

2.0 Purpose and Scope Two locations are proposed for Horizontal Directional Drilling (HDD) installation of the pipeline. This report summarizes the feasibility of the HDD design, addressing anticipated installation loads, installation and operating stresses, comparison of modelled formation limiting pressure vs drilling annular pressure, and potential mitigation measures for these two crossings.




- ASME B31.8 (2016)



General crossing design parameters are provided in Table 1 below.




Table 1 – Crossing Design Parameters

Parameter Unit Alexandria

Service Natural Gas




Pipe OD in 6.625

Pipe WT in 0.28

Pipe Grade ksi B




Coefficient of Fluidic Drag psi 0.025

Notes:

Ground profiles are based on survey.




4.0 Geotechnical Conditions A geotechnical investigation consisting of four soil borings were completed. The results of the geotechnical field and laboratory programs are provided in “Geotechnical Data Report – New Prague Line, New Prague, Minnesota,” Terracon Consultants, January 15, 2019 (Project MP185036D).

The borings generally encountered topsoil underlain by medium stiff to stiff sandy lean clays, however, one layer of lean to fat clay was also encountered.

Groundwater was observed at varying depths at the times the borings were performed and, where observed, was likely perched within water bearing soils bound by clay layers. The soil borings were not left open long enough for hydrostatic groundwater levels to equilibrate and additional testing or observations would be required to evaluate long term groundwater levels. Seasonal and annual fluctuations of groundwater should also be anticipated.

Subsurface conditions are briefly summarized in Table 2 below, focusing on qualitative features relevant to the feasibility of HDD construction. Evaluation of formation limiting pressure is based on simplified stratigraphies and what are considered to be conservative parameters for the soil properties for characteristic soils, see section 7 below.

5.0 Crossing Design Summary Summaries of each crossing design and HDD profile are provided in Table 2 below.




Table 2 – Crossing Design and Bore Profile Summaries


(Drawing Number)


Distance (ft) Features Avoided by

Crossing Notes on Crossing Alignment, Profile

and Workspace Notes on Drilling/Boring and Pullback

Operations

Unfactored Pull Force & Anticipated Drill Rig Size (for site layout and drill parameter assumptions)

Relevant Soil Borings & Notes on Geotechnical Conditions

NPB-P4-1 (HDD) 290 Driveway

Alignment is straight and workspace is considered adequate. One pullback section is expected.


Boring Log No. B-1/B-2 The principal strata encountered was medium stiff to stiff sandy lean clay.

NPB-P4-2 (HDD) 641 Wetland & City Road 143

Alignment is straight and workspace is considered adequate. One pullback section is expected.


Boring Log No. B-3/B-4 The principal strata encountered were soft to stiff sandy lean clay and lean to fat clay.




6.0 Installation and Operating Stress (HDD only) Installation and operating stresses were evaluated for the drills, based on the proposed bore profile. All acceptability requirements for stress, per ASME B31.8 and PRCI PR-227-9424 are satisfied.

Table 3 below provides the maximum installation and operating stresses.

Table 3 – Maximum Installation and Operating Stress

Crossing Maximum Installation Stress (Unity Check based on API

allowable – See Notes 1 & 2)

Maximum Operating Stress (Unity Check based on PRCI shear

stress allowable of 45% SMYS)

P4-1 0.37 0.90

P4-2 0.39 0.90 Notes:

1. A tensile stress limit of 60% of SMYS (based on API RP 2A-WSD R2014) is used instead of 90% of SMYS (as per PRCI PR-227-9424 2008.)

2. The maximum recommended pull force for the NPS 6 pipe specification is 100,000 lbs. In the case of the product pipe being stuck during pullback, more detailed evaluation may be required to determine limits for maximum pull force, maximum hammering loads and hammering duration.

7.0 Hydro-fracture Assessment (HDD only) Hydro-fracture assessments are based on comparing the modelled maximum formation limiting pressure with the minimum drilling fluid annular pressure.

The maximum formation limiting pressure was modelled based on industry accepted cavity expansion, “Delft”, method. Soils were treated as:

- Purely cohesive with undrained shear strength based on correlations for of SPT-N values with unconfined compressive strength. The correlated unconfined compressive strength is divided by two for the corresponding shear strength.

The minimum total annular pressure consists of components for static head and frictional losses in the bore. Parameters for the pilot bore diameter and drill rod size were assumed based on expected drill rig sizes. Parameters for drilling fluid density, viscosity and yield point were assumed based on typical values.

Table 4 below provides a summary of the hydro-fracture assessment, including the minimum factor of safety within the central length of the drill and potential mitigation options.




Table 4 – Summary of Hydro-fracture Assessment




P4-1 1.58 (45 ft from the exit side) As modelled, there is a high risk of inadvertent returns in the last 15 ft on the exit (east) side. The high risk is small and within our workspace.

P4-2

2.92 (middle of the drill alignment) 1.23 (80 ft from the exit side)

As modelled, there is a high risk of inadvertent returns in the last 90 ft on the exit (west) side. The high risk area is approximately 30 ft outside the tree line of the invasive species area. Mitigation may include partially tripping the drill pipe to clean/condition the bore prior to drilling the last 120 ft of the drill at reduced pressures.

Notes: 1. General mitigation measures include: - Deeper entry/exit pits. - Manage drilling fluids by maintaining drilling fluid density and sand content, and

balancing flow rates and drilling speed. - Adjust fluid composition with changing soil conditions, considering the use of additives

for lost circulation, viscosifiers, flocculants or coagulants. - Reduce pumping for the last portion of the pilot drill, relying on tripping of the drill rod

and minimal mud circulation to clean the pilot hole. - Use conductor casing to stabilize the borehole for a portion of the straight tangent of

the bore profile at the entry and/or exit. Conductor casing shall be sized based on the final reaming pass.

Factors of safety greater than 1.5 are considered to have a low risk for inadvertent returns with a competent standard of care. Factors of safety between 1.25 and 1.5 are considered to be medium risk, but manageable with attention to matching drilling production with fluid management. Factors of safety less than 1.25 are considered to be high risk and suggest re-evaluation of the bore profile, but are still manageable by an experienced HDD Contractor with appropriate mitigation measures.

The minimum total annular pressure is based on assumed drilling parameters, and should be re-evaluated based on the HDD Contractor’s execution plan.




8.0 Conclusion & Recommendations All of the proposed crossings in the New Prague Branch Line Loop Project are considered feasible:

- Based on the subsurface investigation, the HDD bore profiles are expected to be drilled through formations that are suitable for HDD. The geotechnical investigation included two soil boreholes for each HDD. These soil boreholes terminated at the appropriate depth and should give a good approximation of the subsurface formations.

- The crossings are considered to be feasible in terms of surface constraints and workspace for operations at the entry/exit locations and pullback section.

- The specified HDD crossing pipe satisfies acceptability requirements for installation and operating stresses.

- As modelled, the hydro-fracture assessments indicate the crossings have low to medium risk of inadvertent returns within the central length of the drills and high risk of inadvertent returns towards the exit. Despite these risks, the crossings are considered to be feasible, and mitigation measures have been suggested to address the risks. The suggested mitigation measures are proven and within the capabilities of experienced HDD contractors.

General recommendations in preparation for construction include:

1. Allowing adequate time for regulatory and permitting requirements;

2. Ensuring that HDD Contractor execution plans reflect practical implementations of the HDD design. Re-evaluation of hydro-fracture assessments based on the HDD Contractor’s execution and fluid management plans;

3. Ensuring clear understanding of the roles of the Pipeline Contractor, HDD Contractor, Environmental inspector, HDD construction inspector and other Company representatives with respect to safety and mitigation/response plans.



Rochester 2019 Expansion Project Rochester Greenfield Lateral



A 4-Oct-2018 IFR TH RC GC B 19-Feb-2019 IFR TH RC GC



Project Title: Rochester 2019 Expansion Project - Rochester Greenfield Lateral

Revision: B

ii





Revision: B

iii

Table of Contents






6.0 INSTALLATION AND OPERATING STRESS (HDD ONLY) .........................................10

7.0 HYDRO-FRACTURE ASSESSMENT (HDD ONLY) ......................................................11





Revision: B

1

1.0 Project Description Northern Natural Gas Company (Northern) proposes to construct and operate approximately 12.6-mile, 16-inch-diameter greenfield branch line which will commence 0.25 mile south of County Road 6 SW and immediately east of 95th Avenue SW in Section 3, Township 104 North, Range 15 West (T104N, R15W), Olmsted County, Minnesota. The proposed branch line will take-off from Northern’s existing 16-inch-diameter MNB73201 La Crosse branch line and 12-inch-diameter MNB73202 La Crosse branch line loop and extend to a new Rochester TBS in Section 14, T106N, R15W, near the northwest corner of County Road 25 SW and 70th Avenue SW in Olmsted County, Minnesota. Northern plans to construct the Project in accordance with the section 7 of the Natural Gas Act, as amended, and Part 157 of the Federal Energy Regulatory Commission’s Regulations. The planned activities described above are herein referred to as the Rochester Greenfield Lateral (Project).

2.0 Purpose and Scope A total of 22 horizontal directional drills (HDD) are proposed for the Project. 13 of the HDDs are designed as site-specific crossings. This report summarizes the feasibility of the HDD design, addressing anticipated installation loads, installation and operating stresses, comparison of modelled formation limiting pressure vs drilling annular pressure, and potential mitigation measures for these 13 crossings.

The remaining nine HDDs are proposed as typical HDDs. These typical HDDs cross roads or small wetlands, have shorter lengths (200-660 feet), and are generally completed within one week. The typical HDDs are considered feasible and are not discussed further. The road-crossing HDDs have a typical profile, which is depicted in drawing RGL-TYP-01.




- ASME B31.8 (2016)






Revision: B

2

General crossing design parameters are provided in

Table 1 below.

Table 1 - Crossing Design Parameters

Parameter Unit Rochester

Service Natural Gas




Pipe OD in 16

Pipe WT in 0.375

Pipe Grade ksi X52




Coefficient of

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