jordan_Outsourcing_book_temp.qxd 06/11/2009 10:46 Page 62
Well Blowout Rates in California Oil and Gas District 4 – Update and Trends
Table 1: Summary of Well Blowout Risks for California Oil and Gas District 4, 1991–2005
Consequences
Blowout During/From Probability Affecting Public Causing Worker Casualty Affecting Environment Duration
Minimum Median Maximum
Well construction – 1 in 2,500 wells 10% (oil- 15% (fatality, severe 20% (>25 30 minutes 18 hours 6 months
non-thermal fields misted houses) burns, concussion) acres affected)
Well construction – 1 in 1,700 wells 0% 10% (foot burn) 20% (<25 20 minutes 6 hours 43 hours
thermal fields acres affected)
Non-thermal 1 in 60,000 0% 0% 0% 3 hours >1 day
production wells well-years
Thermally enhanced 1 in 20,000 20% 0% 60% (~25 4.25 hours 6 hours 12 hours
production wells well-years (evacuation) acres affected)
Steam injection wells 1 in 10,000 0% 0% 80% (primarily earth <5 minutes 2 hours 5 days
well-years displacement – 1/3 to
400 cubic yards)
Shut-in/idle and plugged 1 in 140,000 0% 0% 25% (displacement of up 20 minutes 3 hours 5 hours
and abandoned wells well-years to 1,200 cubic yards of earth)
Figure 3: Updated Timeline of the Total Number of Well Figure 4: Number of Well Blowouts Relative to Activity Through
Blowouts in District 4 Time in California Oil and Gas District 4
18 18
16 16
70,000
14
14
Inactive wells
35,000
12
12
0
40,000
10
10
Fluid volume 20,000
8
(MMbbl at wellhead condition)
8
0
Blowouts/year
50,000
6
Blowouts/year
6
Active wells
25,000
4
4
0
2
7,000
2 3,500
0
1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
Well construction events
0
0
1991–2005 2006–2008
1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005
Total annual
Annual Moving quadrennial average
Total quadrennial average
Modified from Jordan and Benson, 2009.
6
Modified from Jordan and Benson, 2009.
6
Figure 5: Total Number of Well Blowouts and Blowouts from Figure 6: Total Number of Well Blowouts and Blowouts During
Steam-injection Wells in District 4 Over Time Well Construction in District 4 Over Time
18 18
16 16
14 14
12
12
10
10
8
8
Blowouts/year
6 Blowouts/year
6
4
4
2
2
0
1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 0
1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005
Total annual Steam injection annual Total annual Well construction
Total quadrennial average Steam injection quadrennial average Total quadrennial average Well construction quadrennial average
Modified from Jordan and Benson, 2009.
6
Modified from Jordan and Benson, 2009.
6
construction declined from about three to one per year over the operation – one each from a steam injector and thermal production
same time period. All six blowouts from 2006–2008 could be fully well. One blowout occurred from an inactive well. The relative
categorised with the available information. Three blowouts occurred proportions of post-2005 blowout types are similar to the proportions
during well construction. Two blowouts occurred from wells in of blowouts from 1991–2005, except for the lack of blowouts during
EXPLORATION & PRODUCTION – VOLUME 7 ISSUE 2
62
Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92  |  Page 93  |  Page 94  |  Page 95  |  Page 96  |  Page 97  |  Page 98  |  Page 99  |  Page 100  |  Page 101  |  Page 102  |  Page 103  |  Page 104  |  Page 105  |  Page 106  |  Page 107  |  Page 108  |  Page 109  |  Page 110  |  Page 111  |  Page 112  |  Page 113  |  Page 114  |  Page 115  |  Page 116  |  Page 117  |  Page 118  |  Page 119  |  Page 120  |  Page 121  |  Page 122  |  Page 123  |  Page 124  |  Page 125  |  Page 126  |  Page 127  |  Page 128  |  Page 129  |  Page 130  |  Page 131  |  Page 132  |  Page 133  |  Page 134  |  Page 135  |  Page 136  |  Page 137  |  Page 138  |  Page 139  |  Page 140  |  Page 141  |  Page 142  |  Page 143  |  Page 144  |  Page 145  |  Page 146  |  Page 147  |  Page 148  |  Page 149  |  Page 150  |  Page 151  |  Page 152  |  Page 153  |  Page 154  |  Page 155  |  Page 156  |  Page 157  |  Page 158  |  Page 159  |  Page 160  |  Page 161  |  Page 162  |  Page 163  |  Page 164