til 2013

Dear readers,

Due to the encroaching holiday craziness, including travel and work deadlines and a flurry of fascinating end-of-the-year reports about water, I’m going to have to sign off for the rest of 2012.  Of course I’m also hedging in case of the end of the world on Friday, as predicted by the Mayans.  Wouldn’t want to waste my time blogging right before the end of the world…

I hope that you all have a wonderful holiday season and safe travels.  In 2013, I hope to write up an analysis of the US Bureau of Reclamation’s recent report on water scarcity and the Colorado River, read the Pacific Institute’s reports on desalination and California’s water footprint, and eventually get back to that water balance of the Los Angeles basin.  If you get bored over the holidays without me, feel free to beat me to all of this!

take care,

Claire

getting carbon sequestration to work

One magic bullet that engineers like to talk about for global warming is carbon capture and sequestration (CCS) — pumping carbon dioxide into the right water-saturated geological formations just might form carbonate minerals, converting carbon dioxide gas (greenhouse gas!) to a greenhouse-neutral rock.  There are some hurdles, though, that haven’t quite been resolved.  Most of the current CCS projects inject the captured gas into oil formations to enhance oil recovery — this is means that some of the gas often comes back out with the oil.  It’s a different task to inject carbon dioxide to form minerals.

First, you have to have the right geochemistry in the water and in the rock.  Carbonates are actually really slow to precipitate, and in some cases in the lab, oversaturated solutions took months to precipitate out solids (chemistry note: thermodynamics is separate from kinetics).  Second, you have to get the pressurization right in the geological formation.  On the one hand, this means putting in the proper well casing and piping (the “walls” of the well hole) — see the BP oil spill for an example of improper well construction.  On the other hand, this means ensuring that the geological formation doesn’t open up cracks under pressure and leak that carbon dioxide back to the surface.  (This is the suspicion of what might go wrong in some fracking, for example: that certain formations might open preferential pathways for migration of gases and solutions upward into overlying aquifers of drinking water.  This is also an unknown, but not one that I’ll address here.)  Finally, there’s the risk that injecting pressurized fluids will lead to increased seismic activity.  This is currently being documented as it occurs, but we’re far from predicting when and where it might occur (other than “in locations where we injected stuff…after we injected the stuff” which isn’t that helpful for planning or engineering purposes).

Well, as usual, scientists are working on stuff that will eventually be useful.  A recent paper evaluated a new way to detect carbon dioxide leaking into shallow soils from deep formations.  Traditional technology has required an extensive collection of background data to understand how carbon dioxide might naturally move through a geological formation.  But the new method uses measurements of nitrogen, oxygen, carbon dioxide, and methane in soil gas to distinguish between naturally occurring processes and an extra influx of carbon dioxide from, say, a CCS injection site.

This is pretty sweet, because knowledge is going to save money on these projects, as well as give clearer answers that the traditional method could.  Plus, this will resolve a big question, at least in my mind, as to the viability of this technology.  We can deal with it if the kinetics of carbonate mineralization are slow underground, but if the carbon dioxide gas leaks back out, it isn’t really sequestered after all…

spy vs. spy, lobbyist-style

I wrote recently about the attempt by the last coal-fired steamer on the Great Lakes, the SS Badger, to circumvent environmental laws that would force it to upgrade to a modern propulsion system.  I really find it hard to justify such an outdated and messy mode of transportation, which dumps 509 tons of coal ash in Lake Michigan every year (an average of nearly one and a half tons per day).  That’s a lot of ash.

Well, the language to exempt the SS Badger from EPA’s oversight was stripped from a U.S. House of Representatives bill just last week.  Advocates from Michigan and Wisconsin had added an amendment to a Coast Guard reauthorization bill to exempt the ship, as a National Historic Landmark, from EPA oversight.  However, the reauthorization bill was passed without the amendment, meaning that the Badger’s permit to operate expires on December 19th, no exceptions.

Apparently, a rival ferry with diesel-powered engines, Lake Express, appealed to its own representatives, including one from Milwaukee, to vote out this amendment.  Lake Express offers ferry service about $50 more than the SS Badger, for service about 1.5 hours shorter (2.5 hours vs. 4 hours).  In a public statement, Lake Express noted that in the SS Badger’s own correspondence with the EPA, the company said it could pay for equipment to eliminate the need to dump coal ash by upping their ticket prices by just $4 per customer — which would still be much cheaper than Lake Express.  In other words, it’s less about the money and more about the effort…

The conclusion from all of this is, two rival companies appealed to rival lawmakers, and despite what might seem like corruption of the legislation process, the best outcome was reached, as far as protecting human health and the environment.  Whether you call the SS Badger’s National Historic Landmark status a loophole or an earmark, it was not successful.  The process works…

taking advantage of messes

A paper came out this week in Environmental Science and Technology, probably my favorite technical journal, suggesting a “risk-managed route” for the Keystone XL pipeline.  The original route made enough stakeholders in Nebraska nervous about their groundwater supplies that the governor requested President Obama to deny the Presidential Permit, and so it was done.  Keystone has a new proposed route, which will avoid much of the Nebraska Sandhills, but still go through some ecologically sensitive areas.  The authors of this paper propose a route that avoids surface water crossings in the canyons of the northern part of the Ogallala aquifer, and instead intentionally crosses spray-irrigated, row-cropped land underlain by nitrate-contaminated groundwater.  The route eventually connects with the existing Keystone 1 pipeline north of the Platte River, rather than the proposed connection in Steele City, NE.

Now, I’m sure that Keystone has its own agenda for why it chose the route it did, and there are parts of this “risk-managed route” that are left unmentioned in the paper (it’s only 5 pages, so it can’t cover everything).  That said, the authors’ proposed route has an interesting idea as far as the irrigated cropland goes.  They assume that pipeline spills are inevitable (over the past 10 years, they cite statistics of 0.8 spills per 1000 miles of pipeline, averaging 364 barrels of oil), and that dilbit will partition into the part that volatilizes (evaporates away) and the part that floats on the water surface (light components called “light non-aqueous phase liquids” or LNAPLs).  The existing irrigation infrastructure is already set up to deal with LNAPL spills in the groundwater: the irrigation wells can extract the water+hydrocarbons, and the irrigation sprayers can enhance volatilization of the components pumped out of the ground.  Interesting thoughts, and true.

The big red flag in my mind is the actual composition of the dilbit (diluted bitumen) to be carried in the pipeline.  Normal crude oil is largely lighter than water, and does in fact float.  But bitumen is more like tar, and it’s diluted with lighter hydrocarbons so it can even flow in pipelines.  I don’t know if bitumen composition is a trade secret or something (I couldn’t find much information), but it’s possible that it would sink under the water table (making it a dense non-aqueous phase liquid, or DNAPL) rather than float.  In fact, the Enbridge spill in Michigan suggests that dilbit will, in fact, sink, though in that case, the dilbit got mixed in with sand and sediment that caused it to sink into the riverbed along 40 miles of the Kalamazoo River.  There’s not much mixing like that in groundwater — things are pretty static.

But think about this: LNAPLs are easier to remediate than DNAPLs, based on the physics of water and non-aqueous phase liquids.  I found a statistic that the average spill cost is ~$2,000/barrel for normal crude oil, but the spill in Michigan is already past $29,000/barrel.  Multiply that by 364 barrels/average spill, and you’re talking a $10.6 million starting point, on average.  That’s an expensive project.

I guess my take-home message is, I like the thinking outside of the box in the paper, but if dilbit is, in fact, DNAPL rather than LNAPL, we need to do a lot more due diligence and risk mitigation before we approve anything.

bad timing for grand ideas

I’ll take a brief respite from my recent oil pipeline kick (more to come later this week) to compare two different news stories: one is the continuing saga of water management struggles in the Missouri-Mississippi River basins, and the other is the attempt to track down new water management strategies for the water-poor, population heavy Front Range region of Colorado.

Over in the Missouri and Mississippi River basins, stakeholders continue to fret about the balance of water flowing through their reaches.  Farmers in North Dakota worry about sufficient irrigation water in the future, as the Army Corps of Engineers considers depleting the 12 years of supply stored in the Upper Missouri’s reservoirs.  (Note to Hetch Hetchy restoration advocates: that’s a lot of supply to be stored.  Engineers must think that excess storage is a hedge against uncertain future conditions, huh…).  Barges in the Mississippi are cutting down their loads, so they can ride higher in the river, and dredging activities to remove natural limestone features along the Illinois-Missouri border have been accelerated.  Don’t let the title of that article fool you — the only water wars in progress are figurative, not literal.

Things could escalate — though almost certainly not to actual violence — if a proposed plan to build a pipeline from the Missouri River watershed to Colorado’s Front Range goes through.  The US Bureau of Reclamation (USBR) is entertaining far-fetched ideas to address Colorado’s limited water supply, including towing an iceberg to California, shipping giant bags of water from Alaska, and yes, building a giant pipeline across Kansas to Denver.  In order to consider these odd ideas seriously, the USBR has started the planning and alternative evaluation process.  I outlined how this generally works in relation to the Hetch Hetchy restoration idea, but suffice it to say, this pipeline is still at the early stages of “tools for decision making” rather than the early stages of design and implementation.

Although this idea isn’t as far-fetched as it first might seem (the pipeline would need to be roughly 600 miles long, only 50% longer than the 419-mile long Los Angeles Aqueduct), I really hope it doesn’t make the next cut for analysis.  The goal in the US should not be to emulate California’s extensive aqueduct network, but rather to implement large-scale water recycling to cut down on net consumption of water by various municipalities or regions.

The timing of this idea is also about as bad as it gets.  Any sign of the Missouri and Mississippi stakeholders getting wind of this idea, and an all-out media war of words will likely ensue.  That’s a good way to ensure that regardless of the engineering feasibility study outcome, the public relations battle will already be far lost.  And who knows, maybe that’s what USBR really wants, too.