More on those historic mercury mines of Marin (the short version)

A rather long note bene: Since I went through so much grief the other night trying to save my old 2020 mercury mine blogpost from Google Blogger AI censorship bots, in desperation I took screenshots of the original post and reposted it on my artist page on Facebook. I also made a very truncated version (below) for the Facebook group, California History as I was afraid the information I had worked so hard for was going to be forever lost. 

The original mercury mine blogpost had its inception Labor Day weekend when I was hiking San Pedro Ridge in San Rafael. We were still in Covid sequestration, and to keep my sanity, I wrote many articles I might not have other otherwise written. 

In this case, I wrote a stub that didn’t go anywhere, no real leads, and then I delved into it again in December 2020. I discovered that I was in over my head with the material, and no matter how I tried, I couldn’t finish the blogpost—partially because I couldn’t find the discrete information I needed. 

And also, I thought I didn’t have the chops to figure out how to present the material. Why a writer, suffering from dyslexia, is a writer is a mystery, but there are many of us out there. It’s not like I’m earning any money off my writing. I’m not getting paid for any of this. I write because I have to.

I suspect my writers’s block, or rather, my revisionist block, was due to the fact that it was too big a subject. The more information I uncovered, the more of the post grew. I was in over my head. I despaired. It was an albatross. But the only way out was through. 

Sometimes I think I can’t write my way out of the paper bag. or, that I don’t have the intellectual  chops. This time I was in one colossal kevlar-lined paper bag, but I persevered. It was probably one of the most challenging blogposts I have ever written. 

My Night Train to Moscow post (which began as an email), my redhead, pacer, bees, and daffodil blogposts also gave me some serious writer’s grief, but at least the posts weren’t banned by Google. 

I face enough unwarranted censorship from Facebook for writing bad similes, or thinking outside the box. I sure don’t need this kind of grief from Google either. I expected better from Google. (Google fail.) I feel betrayed.

The other day, when I made another stab at revising the original blogpost because of a Facebook post on the old mines in Lost Marin, I finally made some serious headway—only to have Google Blogger take it down and literally trash my blogpost, then reinstate it—some 30 times. When Google takes down a blogpost, you can’t even see it. It just disappears into the ether. No warning. Poof! Gone.

A while back, Google suffered a serious systemwide matrix glitch and took down multitudes of my innocuous posts—only to reinstate them later but I had to physically find my blogposts in the trash and then reinstate them. Before that, I didn’t know that Google had previously removed some of my other posts. Sadly, some of those posts are lost forever.

Thinking it was an email spam, I ignored the red warning label Google had slapped on my posts, and I lost my Juanita Musson memorial post, plus others. I reasoned, how could a memorial post be considered spam? It was not logical, as Spock might have said. But it was for real, only I found this out in arrears. 

I was able to salvage some of the removed old posts from first drafts that I had stashed elsewhere, but not all. Not Juanita in the bathtub. I despaired thinking I had lost all my revision work on the mercury mine post. I was 12 hours deep into it. So, of course I fought furiously to save my post, and to get it reinstated. Again and again.

Now I’m afraid to make any further changes on my original mercury mine post for fear of triggering the AI bots. Google no longer adequately warns you that it is removing posts. It no longer uses the red banner. And it took a long time for a Google warning to show up, explaining what the reasons were for banishment: violating community standards.

Google warned I was violating community standards, but it didn’t specifically say what. I had no idea. Googling it did not elucidate or shed any light on the subject. So, I kept removing images, revising, checking on all my links, and nothing worked. I wasn’t over quoting anyone, and it was my own intellectual property, not to mention, photos. And all the graphs I used were from publicly funded agencies, therefore within fair use parameters. I couldn’t remove the ban. I despaired.

A Google email eventually appeared, claiming this time that I was violating community standards by promoting or selling controlled substances. Huh? How is a blogpost on historic mercury mines even remotely considered to be promoting a controlled substance? Maybe it was the word “mine” itself that triggered the bots. So, this post below is a test of sorts.

(I am not trying to bite the hand that feeds me. If it wasn’t for Guy Kawasaki’s evangelical support of Google Blogger, I would not have delved so thoroughly into the new medium of cyber-writing. It all began innocently enough, I had lost some of my earlier poems to ASCII gibberish, and decided to put them online. Then I discovered I could back-post my work. One thing led to another. MySpace was no longer cutting it. It was a grand liberation to be free of the physical page. As it is, I now have 5000 blog posts. I must admit, I feel betrayed by Google at this point.)

See, during one of those rare moments, when I could actually re-access my ephemeral albeit temporarily reinstated mercury mine blogpost, I took screenshots of it and posted it on Facebook so I wouldn't lose my work completely. I also made a truncated version for a Facebook group I belong to, California History. I have previously taken several of my blogposts and revised (shortened) them for the group. 

Then I realized that the revised post I wrote for California History  is also a separate entity. New work. Probably closer to what I had hoped to originally write. It’s posted below. Now watch, Google Blogger will ban this blogpost too. Don’t worry. This time I have a link to someone who works at Google and I will complain mightily. How’s that for throat-clearing? Are you still there, Dear Reader?

Historic mercury mines in the North Bay (below is a truncated version of my original post. Click on the link/title for full post and research notes).

When I was a child, I was fascinated by my uncle’s old mining survey maps of Bolinas Ridge and Mt. Burdell dotted with old cinnabar (and copper) mining claims. Curiosity got the best of me.

Our red California earth is oftentimes a sign of the presence of iron /hemitite, or cinnabar (Remember Napa’s Silverado Mine on Mt. St. Helena, made famous by Robert Louis Stevenson’s 1884 novel, The Silverado Squatters?)

There are several historic cinnabar mines in Northwest Marin, including four at the Gambonini Ranch, near Solajoule Reservoir, some sites on Mt. San Antonio, and also on the ridges above Novato. The old mine shafts on San Pedro ridge in San Rafael seem to be gold claims. But where there’s gold, there’s cinnabar.

During the Gold Rush, cinnabar ore mined in California, for mercury, was originally used for silver and gold extraction. The crushed ore was processed in high-temperature smelting ovens. 

Those unstable leftover cinnabar tailings are what has caused the mercury runoffs into our watersheds, including in the San Francisco Bay—destroying one of the most fertile marine ecosystems in the world.

There are numerous historic cinnabar mine tailings throughout Marin and Sonoma counties, some that have also added to the high mercury levels in several of our reservoirs, including Bon Tempe, Solajoule, and Nicasio reservoirs and their drainage watershed, Tomales Bay. 

The fish warning signs that rim several of our reservoirs serve as a grim reminder that mercury poisoning is cumulative. Tomales Bay in Northern Marin County has higher mercury levels than San Francisco Bay—and it’s not from naturally occurring cinnabar deposits, as the mineral mercury oxide is inert unless it’s been heated and extracted.

According to the California Office of Environmental Health Hazard Assessment (OEHHA), there is an fish advisory or warning that Nicasio and Solajoule Reservoirs contain methyl-mercury, as does Bon Tempe Reservoir on the slopes of Mt. Tamalpais, which once hosted several historic mines, including mercury, copper, gold, and even a nickel mine.

I assume that the rest of the Marin Municipal Water District (MMWD) reservoirs (our drinking water supply) also contain trace amounts of some form of (inert) mercury too as they’re all downstream of Bon Tempe dam and empty into each other, exiting via Kent Lake into Lagunitas Creek that drains into Tomales Bay. 

Naturally occurring mercury oxide does not enter the food chain the same way manmade methyl-mercury does. But at the Nicasio Reservoir methyl-mercury pollution is significant enough to trigger OEHHA advisory warnings about cumulative mercury poisoning from carp, sunfish, black, and large-mouth bass species (apex predators such as bass contain the most cumulative methyl-mercury in their systems). 

Why Nicasio? It doesn’t butt up against any known mercury mines, it doesn’t share the Solejoule Reservoir watershed to the north where there’s also an OEHHA advisory warning for black bass and crappie.) Why am I mentioning Solejoule? because in 2000, it became a Superfund cleanup site.

In a nutshell, in 1964, a PG&E subcontractor, Oakland-based Buttes Gas & Oil (BG&O), ran a lucrative open pit mercury mining job at Gambonini Ranch near Walker Creek in northwestern Marin. 

But in 1970, when the price of mercury fell, BG&O pulled up stakes and left the open pit mercury mine tailings exposed to the elements behind an earthen dam that epically failed during a series of fierce storms in 1982—which dumped ungodly amounts of leached methyl-mercury into Tomales Bay. More than in San Francisco Bay! 

BG&O had leased the land from Alvin Gambonini’s father from 1964 to 1970, never disclosing to the Gambonini family the potential dangers involved with the toxic heat-processed mine tailings to extract the mercury, or that the leftover toxic mercury particulates leach out of the rock tailings whenever it rains. (I wanted to ask, what about all the cows?) 

BG&O never sealed the four mines, nor capped the tailings. It took nearly two decades for the EPA to discover the mishap. It triggered a $3 million Superfund cleanup in 2000. 

Back to Nicasio Reservoir. The methylmercury is coming from somewhere. Not from abandoned mercury mines upstream that I know of, or from the isolated Solejoule Dam which empties into Walker Creek. Question is, from where?

However, some of those old red earth mine sites really were manganese, or hematite, a type of iron, not cinnabar—like the Sausalito mine, and the prehistoric hematite site on Mt. Burdell. Inert red dirt. Sometimes a red rock quarry is just a red rock quarry. Just don’t eat the fish.

Wild swan at the Chileno Valley laguna, victim of the drought

I fear this wild swan is a victim of the drought. The Laguna de San Antonio aka Laguna Lake!) in Chileno Valley, in both West Marin, and Sonoma County, has completely evaporated. A first. Technically the laguna is a very large vernal pool, the largest in California, but this is the first time I’ve seen it bone dry. See that swan’s big black foot? It was always suspended above the water line. S/he was constantly grooming under that protruding foot, it stuck out like a small black sail. I’ve observed this particular bird for hours. It could not put that leg down, and the wing too was permanently canted up. That said, it could chug along pretty well on one leg. With only one functional leg, s/he managed fine in this part of the laguna, but never migrated to the other side of the lake with the other swans, or to the Arctic either. No idea if it’s a he or a she—we like to assign gender to things perhaps to personalize our experience—but it never had a mate or any babies. It usually swam alone, apart from the flock. I’m not even sure if it’s a mute swan or a tundra swan. There are both found in the laguna. After hauling out the old photos to post here, I can see it’s a mute swan—an invasive species. Am I supposed to suddenly hate it because it’s not native? But I have unconsciously named it. Its beak is somewhere in between the two species. Tundra swans have yellow embedded on their beaks, this one has scarlet on its beak. Maybe that’s why it doesn’t commute. It doesn’t know where to go. Besides, it probably has been anchored to this spot of the lakebed for so long, it has lost the urge. Mute attestation. I thought maybe that fishing line filament caught up on its leg, but I never could get close enough to see. I thought about calling a wildlife rescue for it, but it seemed to be managing OK. Besides, can you imagine trying to wrestle a swan? I’m no Leda. Now, the laguna is only a mudflat, the lake is gone—and on the opposite shore, I saw what looked like a dead swan. A one-legged swan, stuck in the mud, sans lake, wouldn’t stand a chance of survival. I’d have to seriously trespass across the mudflats in order to cross the lakebed in order to verify it. I wasn’t quite brave enough yesterday. I did walk a third of the way across the lakebed. Yesterday, I found the tip of an old yellow fishing rod in the mud right about where this photo was taken. I imagined a scenario that the swan was anchored to that same spot via that fishing pole. It grew used to its confinement. Maybe that’s why it didn’t join the others when it eventually broke free. It couldn’t. Someone said the leg looks dislocated. Perhaps the bird eventually broke free of its mooring—perhaps dislocating its leg in the process. A one-legged swan, stuck in the mud, sans lake, wouldn’t stand a chance of survival. There used to be a lot of fish in the laguna. Bass, catfish, sunfish. Michael from Petaluma stopped to talk, and told me fishing stories of his youth. The one that got away. How he threw them all back. No fish now. Only the memory of fish. There are several new Turtle Crossing signs. At least the western pond turtles can burrow in the mud and hibernate. Can catfish hibernate too? I didn’t see any fish carcasses in the desiccated and cracked mud. But then I wasn’t looking for them. I could see on the far shore, a dead bird and it looks like a swan just by its girth—whether it’s that swan in question, I have no idea. As I stood in the middle of the lakebed, a white feather came tumbling toward my feet on the breeze. Perhaps a parting gift. And yet I mourn its loss.

Historic mercury mines in the North Bay

 

Note bene: Under construction. Any info on mercury mines would be appreciated.  FWIW, every time I make an edit, Blogger keeps taking this post down, claiming it "violates community standards."but it doesn’t specify what it wants me to remove. I don't see how historic information from public sources violates any standards. All the research, and the writing is my own, and the photos too. Most of the information and maps were created via government funds, and should be copyright free or fair use. Plus I've provided the links. 

A Facebook reader posted a comment that there was cyanide runoff in Halleck Creek, under my Facebook post on the Nicasio dairies that were drowned during the construction of the Nicasio reservoir in the Lost Marin group, and I was off and running—right off the proverbial cliff. Was there any truth to that rumor? Or did he conflate mercury with cyanide? (According to WHO, low levels of cyanide are in our drinking water— usually related to mining activities, not naturally occurring sources.) 

My uncle, who was a surveyor, had some survey mining maps from long ago. I would give my eye teeth right about now to have them back. But the storm of 1984 took out my storage shed. I decided to go with the mercury interpretation instead of cyanide, because mercury mines have a tumultuous history in California.

What  I have mercurially uncovered so far:

According to the California Office of Environmental Health Hazard Assessment (OEHHA), there is an fish advisory or warning that Nicasio Reservoir mud contains methyl-mercury, as does Bon Tempe Reservoir on the slopes of Mt. Tamalpais, which hosted several historic mines, including mercury, copper, gold, and even a nickel mine. 

And I assume that all the rest of the Marin Municipal Water District (MMWD) reservoirs (our drinking water supply) also contain trace amounts of some form of (inert) mercury too as they’re all downstream of Bon Tempe dam and empty into each other, exiting via Kent Lake into Lagunitas Creek that drains into Tomales Bay. Naturally occurring mercury oxide does not enter the food chain the way methyl-mercury does.

But at the Nicasio Reservoir methyl-mercury pollution is significant enough to trigger OEHHA advisory warnings about cumulative mercury poisoning from carp, sunfish, black, and large-mouth bass species (apex predators such as bass contain the most cumulative methyl-mercury in their systems). Why Nicasio? it doesn’t butt up against any known mercury mines, not like the unrelated Solejoule Reservoir watershed to the north (there’s an OEHHA advisory warning for black bass and crappie. There’s more on Solejoule dam methyl-mercury pollution below.)

I don’t know if Halleck Creek, a tributary of Nicasio Creek that feeds the reservoir, also has mercury in it. If so, then there’s probably an old mine shaft or two somewhere up-canyon on Big Rock Ridge. There is Lunny’s (LaFranchi?) gravel quarry across the way, but I don’t think they use cyanide for rock blasting! Nor are they transporting mercury ore for their gravel business as it wouldn’t be very good for business.

Note the MMWD mercury warnings are in English, Spanish and Vietnamese.

The fish warning signs along the Nicasio Reservoir serve as a grim reminder that mercury poisoning is cumulative. Mercury oxide is a naturally occurring inert mineral in the soil, but there are numerous cinnabar mine tailings throughout Marin and Sonoma counties that have added to the mercury levels of our reservoirs, not to mention, Tomales Bay. (Why I won’t eat Tomales Bay oysters….)

Red earth is often a sign of the presence of cinnabar (Remember Napa’s Silverado Mine on Mt. St. Helena, made famous by Robert Louis Stevenson’s 1884 novel, The Silverado Squatters). And if there were heat-processed mine tailings to extract the mercury, then the leftover mercury particulates leaches out of the rock tailings whenever it rains. 

But some of those old red earth mine sites were hematite, a type of iron, not cinnabar—like the Sausalito mine and the prehistoric site on Mt. Burdell. Inert red dirt. Sometimes a red rock quarry is just a red rock quarry. 

That said, there are also several historic cinnabar mines in Novato (an unnamed claim, the Mazza Ranch Prospect, and Gaul mines), and other mine sites in West Marin. I remember seeing an old mining map of Bolinas Ridge dotted with several old cinnabar (and copper) mining claims. And another potential cinnabar site is on Elephant Mountain near Black Mt. Ranch and Platform Bridge, though only a gravel quarry is listed on the other side of the mountain.

Mercury ore mined in California, originally used for silver and gold extraction, was processed in high-temperature smelting ovens. Those unstable leftover tailings are what has caused the mercury runoffs into our watersheds, including in the San Francisco Bay. But Tomales Bay has higher mercury levels than San Francisco Bay—and not from naturally occurring cinnabar deposits, as the mineral mercury is inert unless it’s been heated and extracted.

The methylmercury is coming from somewhere. Question is, where?

Moving north to an adjoining Tomales Bay watershed (Walker Creek), on Hicks Valley Road, as you make the turn past Lincoln School, there’s a rock quarry at the top of the ridge to your left, (Hammock Hill) the exposed Franciscan rock is as red as can be. It looks like mine tailings galore. But not even a rock quarry is listed on that hill, though I can clearly see it from the road.

Rancher Sam Dolcini said it was a historic gravel pit used for making roadbeds. However it’s also a fair distance from Hick’s Mountain (see mining list) and Hick’s Valley Road. And it’s pretty darned red for Franciscan strata. It could also be an old Native American hematite mine. 

Question is, why did the Marin County road builders go all the way up that mountain for gravel? Surely there were more accessible rock outcrops? Maybe it was a speculatory dig that didn’t pan out—the entire northern Marin region has several mercury mines.

Sweetwater Springs mine on Mt. Jackson. Michael Kiesling photo

A little retrospective on reusing mine tailings, which was viewed as an easy source of cheap gravel. In Sonoma County, ca. 1974, the Guerneville sewage plant used mercury-laden tailings from an abandoned mine on Mt. Jackson for roadbeds. (I once hiked up to the Sweetwater mine via an eroded mule trail off Sweetwater Springs Road.) Luckily, it was a tempest in a teapot, the tailings were found to be inert, there was no leeching mercury. (See Mercury Rising 1999). The unlisted Hicks Valley rock quarry on Hammock Hill could be an old prospector site, and a gravel pit for road bed material. Both.

Hammock Hill, Hick’s Valley Road c Maureen Hurley 2020

There’s another rock outcrop that was probably also mined for roadbed material at the Point Reyes-Petaluma/Red Hill Road and Nicasio Valley Road junction at the old Gallagher Ranch. Geoff Davis said there was also cinnabar present there too, but it looks like it’s a limestone outcrop, or a ribbon chert reef, not cinnabar. Half the rock outcrop is gone, and other outcrops were left untouched. Apparently the host rock for mercury ore is serpentinite from the Upper Jurassic period. So, wherever there’s serpentine? All of West County!

This outcrop was twice as big, was it used for gravel or a mercury prospect?

Also within the Walker Creek watershed, the worst (and latest, 1970) mercury mine offender of all was the Gambonini Ranch mine complex on Walker Creek Road. The Gambonini Ranch family was not the problem, PG&E was, as they, or rather a sub-contracted mining company, Buttes Gas & Oil Co., leased at least four mines—the Gambonini, Turner, McFarland and Buena Suerte mines. When the mercury ore ran out, and the mines were “closed,” Buttes Gas & Oil Co. got off scot-free by claiming bankruptcy in 1985, leaving the state of California holding the bag, and liable for a massive Superfund cleanup. 

You can explore the types of mines at Minedat. Most are mercury mines.

(You can explore the types of mines in the North Bay at Minedat. Most are mercury mines. See also the the Cycle, and Franciscan mines. I know they exist, but can’t find supporting data, the adjoining Edwards  mines (Panco No. 1; Chileno Valley; Bueno Chilano; Chileno Valley), and Bently Ranch.) And there is the mercury Bivalve Mine, near Soulajule Dam, and another mercury mine, Petaluma Mine (Superior Gypsum Company Mine), on Red Hill Road.)

Not only was liquid mercury useful in extracting silver and gold ore from mine tailings during the gold rush, it was used for barometers, thermometers, clock pendulums, dental amalgams, auto parts, batteries, plating silver mirrors, fluorescent bulb filaments, and delicate electronics. The military also used liquid mercury for calibrated gauges, ammunition primers, and detonators, so it was a valuable restricted resource. (Military mercury uses PDF.) 

Until recently, liquid mercury was also used in the construction of legacy PG&E electrical transformers. Later, PCB laden oil was used. (Sources of PCBs and Mercury contamination). Curious, I can’t find information on how PG&E used mercury. I found this downloadable PDF from Internet Archive Scholar, The Needs of Miners: Political Ethics, Mercury Abatement, "The need for a global mercury pollution reduction strategy emerged from scientific revolutions of the 1950s and 1960s.” Mercury was becoming increasingly scarce during the 1960s, which drove its value through the roof. 

Cool old trucks at the Gambonini Ranch c Maureen Hurley 2019

Back to the Gambonini Ranch story, in 1964, a PG&E subcontractor, Oakland-based Buttes Gas & Oil, did a blitzkreig open pit mining job and in 1970, when the price of mercury dropped, they folded shop and left the open pit mercury mine tailings exposed to the elements behind an earthen dam that epically failed during a series of storms in 1982—they never sealed the mines, nor capped the tailings. 

Meanwhile, in 1977, Buttes Gas & Oil claimed bankruptcy and suspended operations in California, leaving the ranch owner Alvin Gambonini holding the bag—environmentally speaking. When methylmercury began showing up in Tomales Bay, it triggered a $3 million Superfund cleanup in 2000. The company had leased the land from Alvin Gambonini’s father from 1964 to 1970, and no one ever disclosed to the Gambonini family the potential dangers involved.

San Francisco Bay Regional Water Quality Control Board, 2012 A state funded agency

Few knew about the danger or full extent of the mercury pollution in the North Bay until significant amounts of methylmercury began showing up in Tomales Bay in 1999 after a series of back-to-back severe storms created a deluge runoff.

“The mercury, in a particularly toxic form called methylmercury, was discovered in a test of Tomales Bay fish conducted in 1999 by the San Francisco Bay Regional Water Quality Control Board.…The mercury is believed to have infiltrated Tomales Bay from an open-pit mercury mine located 6 miles upstream from 1968 to 1972. The mine is now an EPA Superfund site.” —Mercury Warning For Fish / 7 Tomales Bay species show contamination, 2000

Since 1964, every time it rained, it means that methylmercury spilled into Tomales Bay. Soulajule Dam, constructed in 1980, conceals an environmental atrocity. Luckily, Soulajule is a reserve reservoir not used for drinking water. The old mines are above waterline, but the lethal tailings around the reservoir are the real problem. And dare I ask the question: what actual earth was used to build that dam?

"If you take a sample of soils anywhere in this county, you will find mercury in it, but in the form of oxide, so it's not a dangerous element," geologist Dylan Whyte says.“The mine site, leased to the Buttes Gas & Oil Co. by Gambonini's parents, is across Wilson Hill Road from the ranch house six miles southwest of Petaluma, and up a steep ridge.” Mercury Rising 1999.

From MMWD: “The District also can transfer Soulajule Reservoir water to other District locations, as needed.” How? I don’t imagine that MMWD would transport water from Solajoule to Nicasio via truck. Someone suggested the water can be moved overland via stock ponds. If mercury oxide is inert, then it suggests that the methylmercury isn’t coming from natural sources. So where is the mercury coming from?