Do You Live Near One of the Top 25 Dirtiest Coal Plants?

There’s a good chance you do. According to the Environmental Defense Fund, twenty of the top 25 mercury-emitting coal plants are located within 50–100 miles of some of the America’s biggest cities.

There are 600 coal plants in the U.S. These 25 coal plants emit roughly 30% of total mercury pollution in the U.S. electricity sector.

So do these plants at least provide an equally high amount of energy? No. According to EDF, while these plants represent one third of mercury emissions, they only provide about 8% of electricity generation.

The harm from coal, if it were actually added to the cost of their power, would make these plants uneconomic, as Climate Progress detailed in February (see Life-cycle study: Accounting for total harm from coal would add “close to 17.8¢/kWh of electricity generated”).

Here’s a list of the worst offenders:

So how bad are these plants? Let’s take a look at a few of the top polluters:

Martin Lake:

Ranked #1 on the mercury list, Martin Lake is considered one of the dirtiest plants in the U.S. Located near Longview, Texas, the plant operator was sued by the Sierra Club in 2010 for 50,000 air pollution violations:

It is the worst power plant for mercury pollution among all U.S. coal plants, emitting 1,764 pounds in 2008, according to the Environmental Protection Agency’s (EPA) Toxics Release Inventory. In Texas, Martin Lake ranked third for asthma-causing soot pollution and was responsible for 13 percent of all industrial air pollution in the state.

Scherer Plant:

The Scherer Plant is #7 on EDF’s list. Located in Juliette, Georgia, the 2.5 GW facility is not only a top emitter of mercury, it’s also been labeled as the largest emitter of CO2 emissions in America.

Scherer is owned and operated by Georgia Power, which also owns the Bowen Plant. Scherer burns through an average of three train-loads of coal per day — coal hauled in from Wyoming’s Powder River Basin, 1,800 miles away. At any given time, BNSF has thirty-six different two-mile long coal trains somewhere on the ten-day roundtrip between Wyoming and Georgia.

Colstrip Plant:

The 2.7 GW Colstrip plant, located east of Billings, Montana, ranks #23 on the list. The plant has installed scrubbers, but it’s sheer size makes it a top emitter.

Gordon Criswell, director of environmental and engineering compliance at PPL Montana, the company that co-owns and operates the Colstrip plant, said that the plant has actually cut its mercury emissions by 85 to 90 percent in 2010 after installing a new mercury control system.

Criswell says the 2009 ranking is due to the size of the plant, where four coal-fired units burn about 10 million tons of coal a year. This is equivalent to one rail car’s worth of coal every five minutes, according to PPL Montana.

Due to increased pressure, a number of other plants have installed scrubbing technologies to reduce heavy metals and particulates. The EPA is also considering new emissions regulations to lower pollution and protect communities located near these plants.

— Tyce Herrman with Stephen Lacey

Related Links:

Below are the earlier comments from the Facebook commenting system:

Richard Brenne

Thanks for this, Tyce and Stephen. That is a great map and a great headline. (The answer for me in Oregon, thankfully, is no.) The best communication is that most specific to the interests of each audience member or reader.


A few questions: Are CO2 emissions directly equivalent to the size and power output of each plant? After CO2, is mercury considered the most dangerous pollutant? What are the primary components of the ozone pollution that Gail at Wit’s End comments about 8 posts below? By the way, that post and her comment and my groupie comment after hers are all well worth re-reading. They’re here:​omm/2011/06/09/240734/clim​ate-change-harm-health-chi​ldren-ozone-pollution-asth​ma-attacks/#more-240734

Do all coal plants need water and has drought or flooding impacted their operation recently? Would this list be the ideal order of coal plants to try to close, or because CO2 is most dangerous should we try to close them in order of their size? What are the most realistic coal plants to try to shut down (Oregon has one coal plant total and that is scheduled to close by 2020.)? Do all 600 coal plants combined average burning about a mile-long coal train a day? (Any answers to any of these questions — and thanks for any links — including my calculation in the comment below would be greatly appreciated, since I’ve done my best to find the best data and want to use these figures in my talks.)

June 10 at 3:00pmTerry Tremwel

I am not an expert on power plant operation, but your questions deserve the best answers I can find. I am an engineer; I have had some related training, though this is not my field.

“Are CO2 emissions directly equivalent to the size and power output of each plant?”

No, the efficiency of various coal-fired plants varies greatly, by the quality of the coal and the system used to convert thermal energy to drive steam turbines. Regarding coal quality, “Coal quality studies are useful in identifying concentrations and distributions of sulfur, ash, moisture content, heat values, and other critical trace elements as described in the Clean Air Act and related Amendments.” (​/coal_quality/ ) and “Most commercial coals range from 3% to 9% ash. A train car carrying 100 tons of coal may be actually carrying 91 tons of burnable coal. With nine tons of clay and sand along for the ride….” and “Sulfur in the coal is released as sulfur dioxide (S02) upon burning. If it is not scrubbed out of the emissions, it will combine with moisture in the air producing sulfuric acid (H2SO4) which makes up some 60 % of acid rain. (The other 40 % is nitric acid from automobiles and trucks.) Coals range from 0.5% to 8% or more sulfur.” (​coalweb/library/science/qu​ ality.aspx ). For example, AEP indicates that Powder River Basin (PRB) Sub-bituminous coal using the best technology (USC) gives off 10% more CO2 than Appalachian Bituminous coal using Integrated Gasification Combined Cycle (IGCC), which lends itself to simpler carbon capture and storage (CCS), but doesn’t yet exist on a commercial scale. (​/App_Media/assets/pdf/ener​gy/summits/13Rencheck.pdf )


Equally important, steam turbine generation varies greatly in the efficiency of the process. Generally speaking, the higher the temperature of the steam the higher the efficiency of electricity generation in a Rankine steam cycle process. In fact, “The thermodynamic efficiency of a Rankine steam cycle increases with increasing temperature and pressure of the superheated steam entering the turbine.” (​docs/reports/beer-emission​ s.pdf ) The rest of the quotes on the steam cycle will come from Dr. Beer’s essay on the MIT website. The tradeoff between ever higher temperatures and pressures of steam and the greater efficiencies to be had is the increasing complexity and risk of failure as the temperatures and pressures go up. The pipe materials and inspection regimen required are ever more demanding. According to Dr. Beer, “The average annual efficiency of the existing US coal-fueled electricity generating fleet is 32%, based on the higher heating value (HHV) of the coal.” In fact, some of the least efficient steam generating units have practical efficiencies as low as 28%. Newer designs push the efficiencies ever higher, with Advanced Ultra Supercritical (AUSC) as the latest designs. Dr. Beer: “Pulverized coal plants with USC parameters of 300 bar and 600/600 °C (4350 psi, 1112/1112°F) can be realized today, resulting in efficiencies of 44% (HHV) and higher, for pulverized coal fired power plants.” The Electric Power Research Institute (EPRI) is developing a program with the goal of “379 bar, 730°C/760°C (5500 psi, 1346°F/1400°F)” performance. In Arkansas, one plant under construction, the AEP Turk Plant, is being touted as the first USC plant in North America, with a design efficiency of 39–40%. Compared to existing coal-fired plants in North America, this efficiency is 42% improved over the worst and 25% improved over the current fleet average. (​obal/utilities/lib/docs/in​fo/projects/TurkPlant/supe​ rcriticalfactsheet.pdf ) Of course, the problem is if the plant is completed it will last an expected 50 years. So, even if a low-efficiency plant were shut down to offset the completion of this plant, the world gets locked into a major (600 MW) generator that spews CO2 for 5 decades unless and until CCS is developed and added to the Turk Plant at great expense (AEP estimates availability in 2020 at an 81% increase in per MWH costs w/ CCS).

“After CO2, is mercury considered the most dangerous pollutant?”

Mercury is bad in areas where it bioaccumulates in fatty tissues of fish and other food animals. It affects fetal growth and development, especially brain development. As with all toxic substances, the issue is concentration relative to the sensitivity of the vulnerable species you are considering. SOx, NOx , ozone and other pollutants each have their nefarious modes of acting. I am not a toxicologist, but SOx deposition (60% of acid rain) affects ecosystems such as lakes and soils. NOx damages lungs and hearts and interacts to help form ozone. Ozone affects the lungs of infants, elderly, and those with lung problems. If you need more detail about toxins, please ask someone who knows better than me. However, I clearly remember J. Arthur Campbell lecturing us as freshmen that the key to any contamination assessment is concentration. Clearly, many parts of the U.S. have toxic levels of each of these substances. On the other hand, CO2 is a global issue more similar to the chlorofluorocarbon issue that came to a head in the late 1980’s and still affects the protective atmospheric Ozone layer. It is a global problem requiring a global solution. The environment has varying capacity to absorb each of these pollutants, but the longest-lived effect is the one we face with CO2. A negative effect on the habitable areas of earth is baked in the cake for perhaps several hundred years, even if we stopped our polluting ways right now. The other pollutants are more localized in effect and shorter lived.

“What are the primary components of the ozone pollution?”

Ozone is a molecule of thee atoms of oxygen instead of the normal number of 2 in the form of oxygen that is essential to life. At ground level, ozone is formed in the presence of sunlight and is catalyzed by molecules like NO2. Ozone is highly oxidizing, or corrosive.

“Do all coal plants need water and has drought or flooding impacted their operation recently?”

Yes, all thermal generation processes use massive amounts of water. At a minimum, they massively raise the temperature of the water used for cooling before it is returned. Usually you see the characteristic cooling towers, often associated with nuclear power plants, that give off steam into the atmosphere. Generating plants are occasionally shut down due to drought or flood.


“Would this list be the ideal order of coal plants to try to close, or because CO2 is most dangerous should we try to close them in order of their size? What are the most realistic coal plants to try to shut down?”

If the goal is to transition to other sources of electric generation capacity with minimal disruption to the economy, then it seems important to me to consider not only the quantity of pollutants, but the efficiency of generation in terms of MWH generated per ton of CO2 equivalent. Eliminate the least efficient plants first, while balancing the grid demands regionally. Drive the decisions by putting a price on carbon, either by a tax on carbon or the use of cap and trade.

“Do all 600 coal plants combined average burning about a mile-long coal train a day?”

The rule of thumb is that a 600-MW coal-fired base load plant uses about one mile-long trainload of coal per day. However, that is greatly influenced by the quality of coal and the efficiency of the plant as discussed above.

P.S. If anyone can correct me on any part of the above, I would appreciate it.

June 11 at 11:13am

Richard Brenne

Terry Tremwell — Bravo! Author! Thank you! I’ve asked a lot of questions here at CP and this is by far the best and most thorough answer I’ve ever received.

I’m just sorry it took me so long to return to find your comment — as a reminder to us all, when you’ve asked questions or see a very special thread developing, return to it for at least as long as the comments are open.

This comment of Terry’s deserves to be archived in a very special place here at CP with comparable comments as a reference piece. It has links, directly answers direct questions, is succinct and comes to the best solution about putting a price on carbon.

Joe — You had mentioned putting the best comments of the week (or all those to date, now approaching a few weeks) in a special category so that they can be revisited. That is an excellent idea, and I’d like to nominate Terry’s. Also you might consider making it a post. It’s that good and would reward and inspire commenters to do this kind of research that helps us all with our understanding.

God (or at the very least Newton) bless Terry and all engineers like him!

June 13 at 2:38pm

Terry Tremwel

Thank you. Kudos are always accepted, though not always deserved. I did spend some time on my response to your questions, but in retrospect I see areas to improve it. In any case, thank you for the kind words.

June 13 at 3:05pm

Jonathan W Smith

An interesting question is how many of these plants could wind or solar could easily replace? Then, of course, is who owns these worst polluters? Who do they support politically? Do these politicians openly support mercury poisoning? Did they vote against a federal requirement for renewable energy portfolios? Do any of the states have renewable energy portfolios? Are any of the portfolios weighted against such poisoning?

June 11 at 12:18pmRichard Brenne

If the average coal plant burns a mile-long coal train every day as I’ve heard, then in America we burn the equivalent of about a 600 mile-long coal train a day. Since we burn 1/7 of the world’s coal, the world burns a 4,200 mile-long coal train a day. That’s over a million and a half mile-long coal train each year (precisely a 1,533,000 mile-long coal train).

Altogether my rough estimate is that we’ve burned about a coal train that would reach the 93 million miles from the earth to the sun. That’s going to leave a mark…

June 10 at 3:02pmBob Connelly

Is there a correlation between the pollution and these being the most politically conservative states in the Union.

June 10 at 2:31pmJoseph Romm

Fossil-fuel money….

June 10 at 2:59pm

Stephen McElroy

They would be uneconomical. Almost as expensive as solar and wind generation. Thank you environmentalists. for stopping wind projects due to the high frequency emissions that are killing bats. Thanks too for stopping the desert solar projects due to endangered desert tortoise. Also by preventing electric transmission lines from actually delivering electricity where needed by blocking transmission through national forests. Stop coal, natural gas, solar, wind, nuclear power generation. Great idea kids. Electric generation who needs it?

· June 12 at 11:20pmGeorge Meade

In Indiana right down the road is a plant. The wind will blow toward InDY alot of the time. We breath in the Toxins all the time. Merc.. Be aware.

June 16 at 12:36amClimate Portals​quake_activity_vs_nuclear_​power_plants/

June 11 at 12:41amRichard Brenne

Just to beat a dead horse with a lump of coal one more time (a favorite Dick Cheney pasttime, I’m told), it doesn’t look like there’s anywhere near 600 dots on the map (and only a handful of coal plants west of the map’s boundary). Is that because those are the total number of sites in the map, but each site might average up to a few power plants?

June 10 at 3:08pmJoshua Trost

Are your children downwind of these poisonous plants?

June 12 at 8:24pm


I live about 100 miles from plant Scherer. How close is too close? I’m upwind.

June 10 at 7:42pm