The Landfill Gas Flare Station

The new flare station, November 2017. The Google Map active in early 2018, although dated 2018, shows the old flare station as it was in early 2016.

The flare station sits on the east side of the park, about halfway between the north and south park boundaries.  Its function is to incinerate landfill gases, mainly methane, and turn them into mainly carbon dioxide.  Methane and carbon dioxide are both greenhouse gases that contribute to the climate crisis, but methane is about 25 times more toxic to the atmosphere than carbon dioxide. 

The area where the park sits was originally tidelands.  The City of Berkeley began construction of the stone dikes that form the park’s borders in 1957.  Four years later, the southern part of the 90-acre area inside the construction project opened business as the city dump.  The dump spread north to the whole enclosed area when the levees were finished in 1968.  Cesar Chavez Park sits on a duvet of dirt spread over an estimated 1.6 million tons of mostly household garbage dumped there between 1961 and 1983.  This number is an estimate, as no records were required or kept at the time.  In places the refuse is about 75 feet thick, tapering to no more than 20 feet thick elsewhere.  The thickness of the dirt cover ranges from about six feet to about 60 feet on the hilltops.  Much of the dirt came from the excavation of the BART tunnel under the Bay.  

Household garbage — “Municipal Solid Waste” or MSW in the trade — consists of a mixture of dry things, like the mattress I dumped there in 1978, and wet matter, like the throwaways in uncounted kitchen garbage pails.  Collection of compostable matter such as Berkeley has today was unknown at the time.  Everything went to the dump. 

This sign in the Berkeley Meadow (Sylvia McLaughlin Eastshore State Park) reminds visitors that they are standing on twelve feet of accumulated garbage

Today’s park is not the only covered-up local dump, by far.  Garbage dumping on the Berkeley shoreline began around 1903, grew with the population, and exploded after the Second World War.  The entire Berkeley waterfront as we know it today is built on garbage.  The Hilton Hotel, the Marina restaurants (except for Skates, which sits on pilings over water), the Berkeley Meadow (today’s Sylvia McLaughlin Eastshore State Park), the bumpy University Avenue stretch west of the freeway, Shorebird Park, Aquatic Park, the North Basin Strip, the current playing fields just south of Gilman Street, everything north of there up to and including Albany, El Cerrito, and Richmond — it all sits more or less on garbage.  The only notable local exception is the Brickyard, where the fill consists of construction debris. Most of the fill under the freeway is sand dredged from the Bay bottom.  

Bacteria go to work on compostable matter almost immediately.  Working in four stages, different bacteria species decompose complex organic matter into simpler compounds, producing water and gases, chiefly methane, in the process.  Bacteria can be powerful gas makers.  In the earth’s early history, long before there were plants, cyanobacteria generated the oxygen atmosphere that we breathe today.  In 1986, methane seeped up through the the lawn seating area of the Shoreline Amphitheatre in Mountain View during a concert and caught fire, an event that made the national press.  There are other similar anecdotes, and there is a long history of methane fires at garbage heaps worldwide, including at the Berkeley dump when it was active.  Eastshore park planners in the 1970s and 1980s were keenly concerned with possible methane leakage all along the shoreline. 

However, no leakage fires have ever been reported from the park.  A 1985 San Francisco Chronicle reporter’s sensational claim that “methane gas from the underlying garbage hisses through crevices” in the dirt cover over the then-closed Berkeley dump had no factual basis.  (Even at the Shoreline Amphitheatre, the gas seeped and did not hiss.)  Already in 1982, a study by Cooper Engineers had found “zero to very low gas concentration readings” here.  A Solid Waste Air Quality Assessment Test conducted here in 1988 detected no organic compounds in surface air samples, and only minute amounts of other contaminants. 

Research paper by Prof. S.C. Whalen showing bacteria in the park’s topsoil turning methane into oxygen

The following year, Prof. S.C. Whalen of the University of Alaska conducted a study of methane emissions at this park, and then published a paper that helped launch a new branch of waste treatment science.  Whalen and his associates found that there was indeed a substantial volume of methane gas present below the soil surface, but almost none above it.  As the topsoil was quite porous, the absence of surface gas could not be explained by some kind of cover seal.  Whalen’s analysis instead found a population of beneficial bacteria in the topsoil.  These bacteria did the opposite work of the decomposition bacteria. These bacteria absorbed methane and turned it into oxygen.  Whalen’s paper has been cited thousands of times and is considered one of the cornerstones of the field of bioremediation, the treatment of waste by natural processes, including beneficial bacteria.  

A number of Berkeley environmental activists, led by landscape architect John Northmore Roberts with a design team that included landscape architect Rich Haag and chemical engineer Richard Brooks, pressed the case for bioremediation in North Waterfront Park and opposed a landfill flare system.  A flare station, after all, is a kind of incinerator, and the Berkeley community, along with many others, had long fought a war against garbage incinerators, and won.  A flare station incinerates the gas from the garbage instead of the garbage itself, but the end result in both cases is that toxic greenhouse gases are discharged into the air we breathe and into the atmosphere.  Bioremediation would be cleaner and far less expensive.

Under the cover lies one of the more than 40 landfill gas extraction wells

These arguments fell on the deaf ears of the Bay Area Air Quality Management District (BAAQMD or “back-mud”).  The District ignored the studies that showed no significant methane at the surface.  It branded bioremediation as “experimental” and threatened the City with heavy fines if it did not install a landfill gas collection and incineration system.  The City did not have the intellectual or political horsepower to resist.  And so, at great and continuing expense, the City installed the system.  More than 40 gas extraction wells lie buried at various points in the park and under the grounds of the neighboring Hilton hotel.  Twelve thousand feet of underground PVC pipe link the wells to the flare station. 

The old flare station with its leaning tower, in 2011

The flare station has three basic parts.  First, a condenser removes accumulated moisture from the incoming gas.  Then a blower injects the cleaned gas into the burner.  The burner, located in the bottom of the tall stack, runs at about 1600 degrees F, sometimes with help from a propane tank.  That temperature is enough to convert somewhere in the high 90 percentiles of methane into carbon dioxide and some byproducts.  The tall stack shields the flames, allows the gas to cool off a bit, and discharges the gas above the height of human eyes and lungs.  A set of electronic controls monitors the process and allows onsite or remote operation. 

In August 2016, work crews led by the City’s engineering division tore down the original flare station built in 1989 and replaced it with a newer model.  Regular park visitors will remember, perhaps fondly, the rusty leaning tower of the old flare installation.  It had to go, not because it was beyond repair but because the quantity and quality of gas coming up was no longer enough to drive it.  Years earlier it had to be throttled down to part time operation, and even then it occasionally sputtered and spit flames like a starving engine.  The new incinerator is smaller and can run on less gas.  It was like trading a rusty old Buick for a shiny new Volkswagen.  I had the privilege of photographing and making videos of the demolition and replacement job.  

The new $750,000 flare station in May 2016 before installation and hookup

My enthusiasm for the new gadget is tempered by the knowledge that the three quarters of a million dollars in taxpayer money that the City spent on it, not counting installation, was a waste of money.  For years now, gas levels at Cesar Chavez Park have hovered just above the arbitrary regulatory threshold where BAAQMD requires operation of a flare station.  Already in 2011, SCS Engineers, the firm that has maintained the system for years, asked regulators for permission to shut it down in view of the low and declining gas levels.  Denied.  

The case for bioremediation is stronger today than it was in 1989.  Recorded gas levels in the system today are highest at the wells in the hotel area, where the land surface is paved and beneficial bacteria can’t work.  Gas emission measurements over the park’s grassy surface are equally negligible in the north, where the garbage is freshest and wells are few, as in the southern areas where the garbage is oldest and wells are numerous.  Bioremediation is no longer “experimental.”  It has become a mainstream industry.  But bioremediation is still not in the BAAQMD vocabulary.  The City of Berkeley still doesn’t have the expertise or the stiffness to challenge the regulatory bureaucracy.  And so we have had to pay for an expensive new system that we didn’t need and that will become a white elephant in the foreseeable future.  

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