Category Archives: water

More Bad News About Ethanol. It Causes Corrosion and Leakage of Underground Fuel Storage Tanks.

Ethanol got its start as an MTBE replacement when MTBE was found to contaminate groundwater. Both are octane boosters. MTBE, as a gasoline additive, was intended to help curb air pollution but was later found to be a carcinogen contaminant of groundwater.

Fast forward to now. We all know that ethanol policy leads to nitrogen groundwater contamination in corn growing regions, but now we are learning that it may also be contributing to leakage in or around underground gasoline station fuel storage tanks. Furthermore, a São Paulo study suggests that using ethanol in vehicles increases ozone air pollution.

After NIST held a two day workshop here in Boulder a year ago to study how the combination of certain microbes with ethanol may be accelerating the corrosion of steel underground storage tanks of gasoline containing 10 percent ethanol, they have released a new report based on their findings. It focused on sump pumps, among other storage and pumping components. The industry is studying whether certain diesel tanks are now leaking because they previously held gasoline mixed with ethanol.

The ethanol people will probably tell you this is yet another conspiracy by big oil against them. The gas station owners and petroleum distributors, on the other hand, will tell you how expensive it is to replace tanks and pipes and fittings and replace them with fiberglass ones to accommodate this product that is government mandated.

In my view this is an important story. There are good options other than ethanol to be used as octane boosters in our gasoline and it is time to consider them.


Here is the July 29, 2014 article authored by Laura Ost for NIST:

NIST Corrosion Lab Tests Suggest Need for Underground Gas Tank Retrofits

A hidden hazard lurks beneath many of the roughly 156,000 gas stations across the United States.

gas tank sump pump
A NIST study found that corrosion may pose a hazard at underground gas storage tanks at filling stations. The study focused on sump pump components, especially the pump casings (labelled #3 in graphic), which are typically made of steel or cast iron.
Credit: Environmental Protection Agency
View hi-resolution image
Gas Tank Corrosion
Optical micrographs of severe corrosion on steel alloy samples exposed to ethanol and acetic acid vapors — conditions typical of underground gas storage tanks — after 355 hours, 643 hours, and 932 hours.
Credit: NIST
View hi-resolution image

The hazard is corrosion in parts of underground gas storage tanks—corrosion that could result in failures, leaks and contamination of groundwater, a source of drinking water. In recent years, field inspectors in nine states have reported many rapidly corroding gas storage tank components such as sump pumps. These incidents are generally associated with use of gasoline-ethanol blends and the presence of bacteria, Acetobacter aceti, which convert ethanol to acetic acid, a component of vinegar.

Following up on the inspectors’ findings, a National Institute of Standards and Technology (NIST) laboratory study* has demonstrated severe corrosion—rapidly eating through 1 millimeter of wall thickness per year—on steel alloy samples exposed to ethanol and acetic acid vapors. Based on this finding, NIST researchers suggest gas stations may need to replace submersible pump casings, typically made of steel or cast iron, sooner than expected. Such retrofits could cost an estimated $1,500 to $2,500 each, and there are more than 500,000 underground gas storage tanks around the country.

The NIST study focused only on sump pump components, located directly below access covers at filling stations, just above and connected to underground gas storage tanks. The sump pumps move fuel from underground tanks to the fuel dispensers that pump gas into cars. These underground tanks and pipes also may be made of steel and could be vulnerable, too. “We know there are corrosion issues associated with the inside of some tanks. We’re not sure, at this point, if that type of corrosion is caused by the bacteria,” NIST co-author Jeffrey Sowards says.

Much of the U.S. fuel infrastructure was designed for unblended gasoline. Ethanol, an alcohol that can be made from corn, is now widely used as a gasoline additive due to its oxygen content and octane rating, or antiknock index. A previous NIST study found that ethanol-loving bacteria accelerated pipeline cracking.**

For the latest study, NIST researchers developed new test methods and equipment to study copper and steel alloy samples either immersed in ethanol-water solutions inoculated with bacteria, or exposed to the vapors above the medium—conditions mimicking those around sump pumps. Corrosion rates were measured over about 30 days.

The NIST study confirmed damage similar to that seen on sump pumps by field inspectors. The worst damage, with flaky iron oxide products covering corrosion, was found on steel exposed to the vapors. Copper in both the liquid and vapor environments also sustained damage, but corrosion rates were slower. Steel corroded very slowly while immersed in the liquid mixture; the NIST paper suggests bacteria may have created a biofilm that was protective in this case.

Although copper corroded slowly—it would take about 15 years for 1.2-millimeter-thick copper tube walls to develop holes—localized corrosion was observed on cold-worked copper, the material used in sump pump tubing, NIST co-author Elisabeth Mansfield notes. Therefore, stress-corrosion cracking is a concern for bent copper tubing because it would greatly reduce tube lifetime and result in leaks.

The NIST test equipment developed for the study could be used in future investigations of special coatings and biocides or other ways to prevent sump pump failures and leaks.

NIST held a workshop in July 2013 on biocorrosion associated with alternative fuels. Presentations and information from this workshop can be found atwww.nist.gov/mml/acmd/biocorrosion.cfm.

*J.W. Sowards and E. Mansfield. Corrosion of copper and steel alloys in a simulated underground storage tank sump environment containing acid producing bacteria. Corrosion Science. July, 2014. In press, corrected proof available online. DOI: 10.1016/j.corsci.2014.07.009.
**See 2011 NIST Tech Beat article, “NIST Finds That Ethanol-Loving Bacteria Accelerate Cracking of Pipeline Steels,” at www.nist.gov/mml/acmd/201108_ethanol_pipelines.cfm.

The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

UPDATE: I have made a correction, since contacted by the author of the NIST article that the NIST conference was actually held in 2013, not a few weeks ago (here in Boulder). I have also added the post from NIST.

More Water Contaminated with Agricultural Runoff: Algae Blooms Create Toxins in Toledo’s Water

The ink was barely dry on my post “Less Corn More Shrimp” concerning the agricultural runoff which creates a Dead Zone in the Gulf of Mexico each year when headlines broke this weekend saying that residents of Toledo were without drinking water.

The reason? Again, agricultural runoff into Lake Erie, and experts tell us that it won’t be the last time this happens. Weather, rains, and poor farming practices all contribute. Better management of waterways would help a great deal.

PBS Newshour explains, here in “How weather and nutrient pollution create fertile conditions for toxic algae blooms”:

Overuse of Groundwater in California Threatens Future Farming and Human Habitation and Requires Enormous Amounts of Electricity

As this California drought intensifies, this week I caught the first headline warning that people may need to be migrated out of areas where its groundwater has been depleted from pumping until exhaustion. As it turns out, there is little or no oversight on using up groundwater in the state, and so the busiest industry there of late has been well drilling.

Stanford is doing a series on groundwater use and policy problems in California, beginning with a great title, “Ignore it and it might go away“, referring to its unregulated use. They tell us that six million Californians rely on groundwater solely for their water supply (mostly in the Central Valley or Central Coast); 85% of California’s population relies on it to some degree; and California’s $45 billion agriculture industry relies upon it. Unfortunately, the state’s antiquated laws concerning groundwater use allow for secrecy, unfettered use, and depletion.

In that article, they inform us what ground water is:

Contrary to a popular misconception of an underground river or lake, groundwater is found in the tiny spaces between sand and gravel and rock. Glaciers left some of that water thousands of years ago, while much of it is regularly replenished by snowmelt, rain and surface rivers and streams.

A lesser known story is how much electricity is required to pump this groundwater, and as it depletes, the amount of electricity needed grows ever larger to pump from deeper depths. Earlier this year, a news reporter friend of mine told me that a large landowner in California’s Central Valley was paying 3 million dollars per month for electricity to pump water. Previously, I wrote about how much energy is required to move water in California.

According to the Association of California Water Agencies, water agencies account for 7 percent of California’s energy consumption and 5 percent of the summer peak demand.

California’s State Water Project uses 2 to 3 percent of all electricity consumed in California, including the electricity required to pump water 2,000 feet up over the Tehachapi Mountains, the highest lift of any water system in the world to supply southern Californians with water.

These percentages don’t include the farmers who pump water out of the ground, plus other users. And we all know that it takes a lot of water to make electricity, too.

Estimates tell us that between 19 – 23 percent of California’s total electrical consumption is used for water pumping, treating, collecting and discharging water, and most of that is used for farming.

We are facing a vicious cycle of quests for energy and water coupled with our human desire to live in the wonderful desert oasis climates.


ADDENDUM . . . Just so happens PBS Newshour covered this same story today, so I am adding their fine video to this post.


To learn more, see my previous post: How much energy does California use to move water?

Also see: California drought: ‘May have to migrate people’

Where is Groundwater Use Unsustainable in the U.S.?


Above: Trends in groundwater levels observed between 1949 and 2009. Negative (red/orange) indicates decline in groundwater level, while positive (blue) indicates a rise in groundwater level.
Source: Columbia Water Center.


My list of concerns about what’s wrong with farm policies here in the U.S. is fairly long, but if I had to name the two that I think are the most important, those two would be better protection of our soil and our groundwater. At present, there are not policies in place which are guarding either of these adequately, and this is short-sighted.

The California drought story has been featured prominently in the news, and included under that topic, we have seen a few articles about the unsustainable reliance upon groundwater for farming there, which is an under-reported story that has grave implications.

Which is why this new U.S. groundwater study out of Columbia University is important.

From the study’s summary:

In addition to confirming alarming depletion in well-known hot spots such as the Great Plains and Central California, the study identifies a number of other regions, including the lower Mississippi, along the Eastern Seaboard and in the Southeast where water tables are falling just as rapidly. Overall, the report concludes, between 1949 and 2009 groundwater levels declined throughout much of the continental U.S., suggesting that the nation’s long-term pattern of groundwater use is broadly unsustainable.

There are farmers in dryland farming regions of Nebraska and Iowa and other Midwestern states who have recently added wells to their farms following the drought of 2012, to help capitalize on strong commodity prices at the time. There is an Iowa community that has seen its groundwater level drop because of an ethanol plant coming in and using groundwater for its industrial water needs. Many communities in Minnesota are facing the problem of nitrate-polluted water in their wells, so they have to purchase and transport clean water for drinking. In California’s agricultural region of Paso Robles, vineyard owners, who use 67 percent of the basin’s groundwater, sued others to preserve their unrestricted access to their rapidly depleting groundwater.

The stories about the use of groundwater go on and on.

Forty percent of our population gets its drinking water from underground aquifers, and groundwater is used for 60 percent of agricultural irrigation, here in the U.S.

Regarding groundwater use, we should remind ourselves of the Native American concept… that we need to make decisions based upon whether or not they will benefit seven generations into the future, even if making those decisions requires having skin as thick as the bark of a pine tree.

Source: Assessment of trends in groundwater levels across the United States. March 2014. By Tess Russo, Upmanu Lall, Hui Wen, Mary Williams. PDF.