A Slurry of Sterilized Waste

Given the ongoing attempt to foment hysteria over the stringently regulated use of cattle manure in organic farming, it’s instructive to consider this story:

Los Angeles officials said Wednesday they are considering a lawsuit to challenge Kern voters' decision to keep L.A. from trucking its sewage sludge to the other county.

The Kern ban came even as L.A. officials launched an experimental project to inject sludge beneath the ground in San Pedro.

Kern voters easily passed Measure E late Tuesday to prohibit the use of highly treated human waste, or biosolids, as fertilizer in unincorporated areas of their county.

Normally, 50 trucks travel from Los Angeles to Kern County every day, each carrying 22 tons of sludge contaminated by pharmaceuticals (among other things).

But never mind about that. The plan to inject sludge “beneath the ground” is far more interesting. The goal is to pump 400 tons of biosolids per day into the sandstone beneath Terminal Island, a doomed artificial island built around a mudflat at the former mouth of the Los Angeles River.

Under the plan, three wells would be drilled at the Terminal Island Treatment Plant. One well would be used to inject the slurry of sterilized waste into the spongelike sandstone where oil has been extracted. Two other wells would be used to monitor the spread of the biosolids in the rock.

"Over time, the expectation is that the material should break down into its constituent products: methane and carbon dioxide," said David Albright, manager of the EPA's groundwater office for the southwest region.

The slurry will be injected about one-half mile below the lowest groundwater level, and EPA officials said the project should have no impact on drinking water.

There's talk of sequestering the carbon dioxide, and storing the methane. As long as nothing goes wrong, it seems that this could indeed be preferable to hauling tons of sludge to Kern County and spreading it on fields, not least because the sludge currently shipped to Kern County comes from the treatment plant on Terminal Island. The question, of course, is whether it's reasonable to assume that nothing will go wrong.

Historical note: As a result of oil drilling, part of Terminal Island had subsided to 29 feet below sea level by the 1950s; the problem was “solved” by injecting water into the former wells. According to the Sierra Club (see previous link), that land is now “literally supported by constant, pressurized water injection.”

(Photo from the Center for Land Use Interpretation.)