(this week's news from the oil patch, with a particular focus on how what we've learned affects a nuclear power plant in Northeast Ohio...)
it appears that the ongoing drop of rigs drilling for oil is finally affecting output, as US production of oil fell for the 2nd week in a row in the week ending April 17th, slipping to 9,366,000 barrels a day from 9,384,000 barrels a day the prior week, matching our output in the 1st week of March...while our daily production has plateaud over the past 6 weeks, it's still been running 14.3% more than the same period last year... even with that higher production, our crude oil imports have been little changed; according to the weekly Petroleum Status Report (62 pp pdf), U.S. crude oil imports averaged about 7.8 million barrels per day in the week ending April 17th, which was 617,000 barrels per day higher than the prior week...over the four weeks ending April 17th, our crude oil imports averaged over 7.6 million barrels per day, 0.9% above the same four-week period last year...so, with our imports of oil relatively unchanged, our higher field production leaves us with more oil than we can use, meaning still more is being put into storage...in the week ending the 17th, U.S. commercial crude oil inventories increased by 5.3 million barrels to a new record of 489.0 million barrels, 23.0% higher than the 397.7 barrels we had stored in the same week last year..
in the week just ended, Baker Hughes reported that US oil patch operators shut down 31 more drilling rigs, leaving 703, while gas operators added 8, bring their total to 225, while the count of miscellaneous rigs increased by 1 to 4...this left 932 drilling rigs operating in the US as of April 24th, which was down from 1861 rigs running in the same week last year, with 831 fewer oil rigs, 98 fewer gas rigs, and miscellaneous rigs unchanged from a year ago...of those left operating this past week, 895 were based on land, which was down by 22 from last week, 3 were on inland waters, which was down from 4 last week, while offshore rigs increased by 1 to 34...the count of horizontal rigs was down by 21 to 720 while the count of vertical rigs dropped by 1 to 121...the greatest reduction of rigs was again in the Permian basin of west Texas and eastern New Mexico, where 12 more rigs were shut down this week, still leaving the area with 246 rigs at week end, while the Eagle Ford of southeast Texas saw another 8 rigs taken out of service...elsewhere, the Williston Basin in North Dakota saw a reduction of 5 rigs, Oklahoma saw 3 fewer rigs, while Louisiana added two...meanwhile, the rig counts for both the Marcellus and the Utica were unchanged, as operators shut down a rig in West Virginia and restarted one in Pennsylvania, leaving Ohio unchanged from last week with 25 rigs still running..
news on new studies on the seismic hazards associated with fracking dominated my news feeds this week, with two releases on state level induced quaking on Tuesday and a major USGS tome released Thursday generating web wide coverage....the major state release, from the Oklahoma department of Energy and the Environment, was actually just an official confirmation of what everyone in Oklahoma knew but had been denying, in that they admitted that the recent 600-fold increase in earthquakes in the state, with some damaging quakes as large as 5.7 and 5.3, was in fact being caused by the injection of oil and gas wastewater into underground formations...now, that this is the case is not new, in that roughly two-dozen peer-reviewed, published papers had concluded that the Oklahoma disposal wells and quakes were connected, but Oklahoma regulators, controlled by the oil industry, had been denying it up until this week, with State Seismologist Austin Holland silenced under pressure from the industry...so it will be interesting to see if they act on what they know before serious damage or fatalities occur...
north of the Oklahoma border, Kansas had been experiencing 17 quakes a month during 2014, an increase from none at all in 2012, and the Kansas Geological Survey linked a rather severe swarm, including a 4.1, to brine injection wells earlier this year....by the middle of March, Kansas regulators imposed sharp restrictions on the state's wastewater injection wells in response to the increase in earthquakes, citing an "immediate danger" to public safety as the reason for limiting the pressure that could be used and the volumes of liquid that could be injected.into the state’s injection wells...so far, since the time the regulations went into effect on March 30th, the area of south-central Kansas that had been plagued with quakes has not experienced another quake..
the dozens of earthquakes that began rattling the North Texas towns of Azle and Reno in November 2013 were the subject of the other state level injection well earthquake study that garnered attention this week, as a seismology team led by Southern Methodist University (SMU) in partnership with USGS developed a model for those quakes that indicated fluid pressure differentials resulting from roughly 70 production wells and 2 wastewater injection wells activated old faults in the area northwest of Dallas that hadn't moved in 60 years...in this case, fracking itself was implicated, as the quakes were the result of the combined actions of high fluid injection rates to the west of the faults and high water removal rates to the east where the fracking was taking place...as a result of this study, the Texas Railroad Commission moved to shut down the two wastewater disposal wells in the Barnett Shale that were linked to the seismic activity in the area..
these small state level studies notwithstanding, the real blockbuster report came on Thursday, when the USGS released their seismic hazard model for 2014, which incorporated induced seismicity into the earthquake risks for 17 new areas in the US, including two in our corner of Ohio...although the USGS had instigated and partnered in many studies of injection well quakes, this is the first time the geological survey itself put the Federal agency imprimatur on injection wells as the cause of the increase in earthquakes....this release updates the 2008 National Seismic Hazard Maps which are used by architects and urban planners in assessing the risk in designing cities and building construction, so USGS is, in effect, putting out a warning here that the potential for injection well earthquakes must be considered in these 17 regions....in many of these cases, the injection of fracking fluids were attributed to have awakened faults that have not moved in millions of years...
although much of the 14.4 MB PDF Report from USGS discusses the methodology of how they arrived at the new seismic risk maps for various regions of the US, using formulas and references that are above my pay grade, there are some images and tables we can look at from the report which will give us an idea of what they're saying and how it affects us...the first map we'll include below, from page 5 (11 of 75) of the pdf, shows the 17 induced seismicity zones that were identified by this report; obviously, the largest is in Oklahoma, and there are 4 such zones each in both Texas and Colorado where man-made earthquakes are known to have occurred...but note that two of them are in Ohio, and both of those are uncomfortably close to us, in Ashtabula and Youngstown...each of those 17 zones where injection well earthquakes have occurred are further described in a table on page 13 (18 of 75) within the report, where they are named and located, the peer-reviewed study that tied the earthquake to pressures induced by injection injection wells is cited, and largest quake and the time window when the quakes occurred is listed...for Youngstown, the period has been between 2011 and 2014, and includes all of the fracking related earthquakes we've discussed in this forum, with the largest quake the new year's eve quake of 2011, which we wrote about here...for Ashtabula, the injection well earthquakes they reference were previously unknown to me as being man-made, and occurred between 1987 and 2007, with the largest a 3.9 magnitude induced quake that occurred during January of 2001...the USGS now considers that earthquakes with a magnitude of 3.0 or greater are now 100 times more likely to occur in these 17 areas than they considered were likely previous to this new assessment...
USGS map of known man-made earthquake zones:
the next graphic from the report that we found instructive is a set of 17 graphs showing when and how many man-made earthquakes occurred in each of the 17 induced seismicity zones that this report highlights, which is taken from page 7 (13 of 75) of the pdf report...note that many of these injection induced quakes predate fracking, and the first known incident of an injection well induced earthquake, at the Rocky Mountain Arsenal in Colorado, didn't even involve the injection of brine, as the army was injecting much more hazardous waste underground there when that series of quakes occurred, which tailed off after they stopped injection and withdrew fluids...also note that only quakes greater than 2.7 are indicated below, and the color coding indicates the USGS catalog that references each of the quakes...again, we know the nature of the Youngstown quakes from our earlier discussions, but the Ashtabula quakes all appear to have occurred prior to taking in waste from Pennsylvania fracking, a time when at least a half dozen wells in the area were disposing of the copious quantities of brine that were associated with the gas wells being operated in the area at that time..note that the scale for each graph is different, with the two Ohio locations just showing a handful of quakes, while the central Oklahoma graph shows the number of injection well induced quakes spiking towards the 1000 mark...
historical man-made earthquake graphs:
that Ashtabula county has been identified as a seismically hazardous area due to induced injection wells earthquakes immediately brought to mind the Perry nuclear power plant, on the lake Erie shore, merely 5 miles to the west...as we have previously discussed, the 4.9 earthquake that stuck the Lake-Geauga county border due south of Perry on January 31st in 1986 earthquake produced ground motion at the Perry Nuclear Power plant that exceeded its SSE design specifications, and it was thus automatically shut down...at that time, i was involved in a county wide effort to stop CEI (now First Energy) from building another 345 KV transmission line corridor through the middle of Geauga county, from Perry to the Hanna substation near Ravenna, and hence i was fairly attentive to what was occurring at Perry...in talking to area politicians and geologists, i found there was considerable speculation that the 1986 Perry quake may have itself been the result of an injection well nearby, although i have to admit that at the time, the idea of a man-made earthquake seemed like a far fetched conspiracy theory to me..
later, when i was made aware that injection wells were still being operated in this area, i checked the literature to see if a connection between injected brine and that 1986 quake had been established...while it has been addressed on several occasions, the connection between the Perry quake and nearby injection wells still seemed to be inconclusive...the following links to abstracts from two papers from the journal Geology below are typical:
- Earthquakes, injection wells, and the Perry Nuclear Power Plant, Cleveland, Ohio: On January 31, 1986, an earthquake of Richter magnitude 4.9 occurred in northeastern Ohio some 17.0 km south of the Perry Nuclear Power Plant (PNPP) and 12.0 km south of the Calhio injection wells. Accelerometers on site at the PNPP recorded accelerations as high as 0.19 to 0.23 g. Many instruments tripped due to high-amplitude vibrations. Microearthquake networks have recorded 16 microearthquakes within 5.0 km of the injection wells with focal depths ranging from 1.0 to 3.0 km. A hydrological model of an anisotropic reservoir 7.2 km wide and 18.4 km long indicates a pressure buildup of 5.3 MPa at the epicenter and 11.8 MPa at the injection well. The assumption of an anisotropic reservoir is consistent with available geophysical and geologic data. A pressure increase of 11.8 MPa, based on stress ratio estimates in crustal rocks in the region, is more than sufficient to induce failure to a depth of 5.0 km. Furthermore, brittle faults and extensive fracture permeability within the basement rocks would allow for the migration of pressure transients to hypocentral distances. The indicated pressure buildup of 5.3 MPa at the epicenter may have been sufficient to trigger the January 31, 1986, earthquake.
- The northeastern Ohio earthquake of 31 January 1986: Was it induced? - On 31 January 1986, at 11:46 EST, an earthquake of mb = 5.0 occurred about 40 km east of Cleveland, Ohio, and about 17 km south of the Perry Nuclear Power Plant. The earthquake was felt over a broad area, including 11 states, the District of Columbia, and parts of Ontario, Canada, caused intensity VI-VII at distances of 15 km, and generated relatively high accelerations (0.18 g) of short duration at the Perry plant. Thirteen aftershocks were detected as of 15 April, with six occurring within the first 8 days. Two of the aftershocks were felt. Magnitudes for the aftershocks ranged from about 0.5 to 2.5. Focal depths for all of the earthquakes ranged from 2 to 6 km. Except for one small earthquake, all of the aftershocks occurred in a very tight cluster with a north-northeast orientation. Focal mechanisms of the aftershocks exhibit predominantly oblique right-slip motion on nearly vertical nodal planes oriented N15° to 45°E, with a nearly horizontal P axis north of east.
- Three deep waste disposal wells are currently operating within 15 km of the epicentral region and have been responsible for the injection of nearly 1.2 billion liters of fluid at pressures reaching 112 bars above ambient at a nominal depth of 1.8 km. Estimates of stress inferred from commercial hydrofracturing measurements suggest that the state of stress in northeastern Ohio is close to the theoretical threshold for failure along favorably oriented, preexisting fractures. This implies that effective stress conditions near the bottom of the two most active wells may be at or near the critical level for incipient failure. Two and, possibly, three earthquakes have occurred within less than 5 km from the wells since 1983. The relative distance to the main shock epicenter and its aftershocks (about 12 km), the lack of large numbers of small earthquakes typical of many induced sequences, the history of small to moderate earthquakes in the region prior to the initiation of injection, and the attenuation of the pressure field with distance from the injection wells, however, all argue for a “natural” origin for the 1986 earthquakes. In contrast, the proximity to failure conditions at the bottom of the well and the probable spatial association of at least one earthquake suggest that triggering by well activities cannot be precluded.
in NRC studies after the Fukushima meltdown, Perry Nuclear was found to be the US nuclear plant most likely to suffer core damage in an earthquake, and that study was conducted based on the 2008 seismic hazard maps, which obviously did not even take into account what we now know about induced seismicity from the area's injection wells...unlike the power plants in California, Perry was not built to withstand an earthquake the size of the Oklahoma injection well induced quake, and while Perry was able to withstand a 4.9 quake when it was a new plant operating at partial power in 1986, it's questionable whether it could withstand quakes as large as 5.3 or 5.7, which by my calculations would be more than 15 times destructive than the 1986 quake...many of the engineered components of the Perry plant were designed to last 40 years, and in some cases of planned obsolescence, not one day longer...thus the plant that safely shut down in 1986 due to the nearby 4.9 earthquake might not do so today under similar circumstances..
unfortunately, our captive ODNR licenses injection wells as a lucrative side line, making 5 cents a barrel on injected in-state waste, and tipping fees of 20 cents a barrel on out of state waste, incentivizing them to encourage other states to dump their waste into Ohio bedrocks...we know of at least 14 injection wells that are apparently still being operated in Ashtabula county, assuming those that were operation as of July of 2012 are still operating...that includes 3 in Lenox, 2 in New Lyme, 2 in Monroe, 1 in Piepont, and 6 at the large injection well complex in WIndsor, near the Geauga county line, and near the site of Ohio's first recorded earthquake in 1823...there are also two injection wells being operated in Lake County, in Painesville and in Leroy, 7 miles from the nuclear power plant...since we know from Oklahoma studies that injection wells have caused earthquakes some distance away, in one well studied case snapping three successive fault planes, one after the other, and that it has been shown that the distance of induced quakes increases with the length of time the injection well has been in operation, and that the magnitude of the largest induced earthquakes tends to increase as the total volume of injected wastewater increases...so it seems that ODNR is just sitting on a time bomb in our area by continuing to license and profit from these injection wells, and all we can do is hope that when the next induced quake strikes our corner of the state, it isn't the big one..
(more at Focus on Fracking)