Lake Combie mercury removal project crosses another hurdle

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Hefty1

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Lake Combie mercury removal project crosses another hurdle

By: Gus Thomson, Journal Staff Writer [SUP]-[/SUP]A [SUP]+[/SUP]A


24-mercury-cleanup-file-photo.jpg

Journal file photo/2009
Mercury from this vial is to be extracted from sand and gravel at Combie Reservoir in Meadow Vista under a program led by the Nevada Irrigation District.



Left
24-mercury-cleanup-file-photo.jpg





Right













With a key state approval in place, a dredging project on Combie Reservoir to remove a toxic legacy of mercury from the area’s gold-mining past could be in position to start this spring.
Plans call for a $6.9 million program over two years to siphon off an estimated 50 to 150 pounds of mercury from Combie Reservoir in Meadow Vista.

They dont know?
At 7 million cost I would think they should have a better estimate???

The quicksilver is left over from the Gold Rush era, when it was used in the process to extract gold from gravel but dumped rather than retained.
The Nevada Irrigation District is working with the Sierra Nevada Conservancy and other partners on a project to dredge an area on the upstream side of Combie Reservoir and extract some of the mercury during the process.
Tim Crough, district assistant general manager, said that the state Water Resources Control Board approved the proposed dredging program this month.
If funding is in place, work could start in April, Crough said.
The Sierra Nevada Conservancy has been a supporter of the mercury removal effort, initially providing $100,000 Taxpayers Money for some of the initial work.
Pete Dufour, conservancy spokesman, said the state agency applauds both the Nevada Irrigation District and Teichert, which has a license for extracting sand and gravel from the site, for looking after their watershed, putting together environmental approvals and obtaining permits.
The irrigation district will be working with Canadian-based Pegasus Earth Sensing Corp. to use suction dredging equipment to help remove mercury from sand and gravel.
Isnt that what we do for FREE!!!

“The ability to effectively remove mercury from sediments that have built up in our water-storage facilities is a major accomplishment that can be replicated at many other sites around the state,” Dufour said.
Three years ago, a demonstration project at the Teichert property by Pegasus indicated that five pounds of mercury could be removed for every five tons of gravel that could be cleaned. We use to demonstrat every year!

Mercury, a byproduct of the gold-extraction process in California from the 1840s into the early 20[SUP]th[/SUP] century, rests at the bottoms of rivers and streams throughout Gold Country. A report from the irrigation district states that when the river is swollen by snowmelt and winter rains, the riverbed is stirred up and mercury released to flow downstream. DAH!
Eating fish from mercury-laden streams has been proven to cause developmental delays in fetuses, infants and children.
 

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Guess what, that Sierra Fund gets to keep the gold they find, and I hear they are setting up to process and sell the gravels. It is amazing our dredges sent out a toxic plume of mercury during gold recovery, and now theirs don't. They are saying they can recover 93% with their dredge, and a stock Keene has been proven to recover 97%. If this ain't a weasel in the chicken house, I don't know what is. I believe in their contract, there are NO guarantees that they will recover anything, but guess what, they still get paid.
 

just checked the Auburn Journal in the comments section - 99% pro -mining. Feel like piling on? Just make sure your comments are factual and with respect!
Jan 22,2013 "lake Combie...."
 

This should anger every taxpayer in the state....We recovered more in a short program than this outfit will over two years, and 7-9 million dollars.

Region 9: Innovative Programs

Serving Arizona, California, Hawaii, Nevada, the Pacific Islands, and Tribal Nations
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[h=1]The Challenge:[/h]Looking for gold in California streams and rivers is a recreational activity for thousands of state residents. Many gold enthusiasts simply pan gravels and sediments. More serious recreational miners may have small sluice boxes or suction dredges to recover gold bearing sediments. As these miners remove sediments, sands, and gravel from streams and former mine sites to separate out the gold, they are also removing mercury.
This mercury is the remnant of millions of pounds of pure mercury that was added to sluice boxes used by historic mining operations between 1850 and 1890. Mercury is a toxic, persistent, and bioaccumulative pollutant that affects the nervous system and has long been known to be toxic to humans, fish, and wildlife. Mercury in streams can bioaccumulate in fish and make them unfit for human consumption.

The Solution:
Taking mercury out of streams benefits the environment. Efforts to collect mercury from recreational gold miners in the past however, have been stymied due to perceived regulatory barriers. Disposal of mercury is normally subject to all regulations applicable to hazardous waste. In 2000, EPA and California's Division of Toxic Substance Control worked in concert with other State and local agencies to find the regulatory flexibility needed to collect mercury in a simple and effective manner. These groups agreed to test two different mechanisms for collecting mercury during the summer of 2000. One approach was to add mercury to the list of materials that are collected at regularly scheduled or periodic household hazardous waste collection events sponsored by local county agencies.
Another mercury collection approach was to set up collection stations in areas where mercury is being found by recreational miners. One possibility would be to advertise a fixed location where people could bring mercury on a specific date and time. Another was to create a mercury "milk run" where state, local, or federal agency staff would come to locations specified by individuals or organizations such as suction dredging clubs, and pick up mercury that had been collected.

The Results:
In August and September, 2000 the first mercury "milk runs" collected 230 pounds of mercury. Not only was mercury received from recreational gold miners, but others such as retired dentists, also participated by turning in mercury that was in their possession. A Nevada County household waste collection event held in September 2000 collected about 10 pounds of mercury. The total amount of mercury collected was equivalent to the mercury load in 47 years worth of wastewater discharge from the city of Sacramento's sewage treatment plant or the mercury in a million mercury thermometers. This successful pilot program demonstrates how recreational gold miners and government agencies can work together to protect the environment. In the summer of 2001, State agencies planned to extend the program to six counties and include collection of mercury at summer mining fairs.

Contact:
For further information, please contact David Jones at (415) 744-2266, [email protected]
Region 9 Topics and Programs | A-Z Index

[h=3]Local Navigation[/h]

Mercury Recovery from Recreational Gold Miners | Region 9: Innovations | US EPA
Print As-Is
Last updated on Tuesday, April 19, 2011
 

Oakview2 said:
This should anger every taxpayer in the state....We recovered more in a short program than this outfit will over two years, and 7-9 million dollars.

Region 9: Innovative Programs

Serving Arizona, California, Hawaii, Nevada, the Pacific Islands, and Tribal Nations
Contact UsSearch:All EPAThis Area

[h=1]The Challenge:[/h]Looking for gold in California streams and rivers is a recreational activity for thousands of state residents. Many gold enthusiasts simply pan gravels and sediments. More serious recreational miners may have small sluice boxes or suction dredges to recover gold bearing sediments. As these miners remove sediments, sands, and gravel from streams and former mine sites to separate out the gold, they are also removing mercury.
This mercury is the remnant of millions of pounds of pure mercury that was added to sluice boxes used by historic mining operations between 1850 and 1890. Mercury is a toxic, persistent, and bioaccumulative pollutant that affects the nervous system and has long been known to be toxic to humans, fish, and wildlife. Mercury in streams can bioaccumulate in fish and make them unfit for human consumption.

The Solution:
Taking mercury out of streams benefits the environment. Efforts to collect mercury from recreational gold miners in the past however, have been stymied due to perceived regulatory barriers. Disposal of mercury is normally subject to all regulations applicable to hazardous waste. In 2000, EPA and California's Division of Toxic Substance Control worked in concert with other State and local agencies to find the regulatory flexibility needed to collect mercury in a simple and effective manner. These groups agreed to test two different mechanisms for collecting mercury during the summer of 2000. One approach was to add mercury to the list of materials that are collected at regularly scheduled or periodic household hazardous waste collection events sponsored by local county agencies.
Another mercury collection approach was to set up collection stations in areas where mercury is being found by recreational miners. One possibility would be to advertise a fixed location where people could bring mercury on a specific date and time. Another was to create a mercury "milk run" where state, local, or federal agency staff would come to locations specified by individuals or organizations such as suction dredging clubs, and pick up mercury that had been collected.

The Results:
In August and September, 2000 the first mercury "milk runs" collected 230 pounds of mercury. Not only was mercury received from recreational gold miners, but others such as retired dentists, also participated by turning in mercury that was in their possession. A Nevada County household waste collection event held in September 2000 collected about 10 pounds of mercury. The total amount of mercury collected was equivalent to the mercury load in 47 years worth of wastewater discharge from the city of Sacramento's sewage treatment plant or the mercury in a million mercury thermometers. This successful pilot program demonstrates how recreational gold miners and government agencies can work together to protect the environment. In the summer of 2001, State agencies planned to extend the program to six counties and include collection of mercury at summer mining fairs.

Contact:
For further information, please contact David Jones at (415) 744-2266, [email protected]
Region 9 Topics and Programs | A-Z Index

[h=3]Local Navigation[/h]

Mercury Recovery from Recreational Gold Miners | Region 9: Innovations | US EPA
Print As-Is
Last updated on Tuesday, April 19, 2011
Click to expand...

Great post, Oakview - I have the same report buried somewhere in my computer. How do we make this a banner/sticky note, as this should be quoted over
and over when talking about dredging/mercury. Somehow this common sense approach to mercury removal got derailed (think Sierra Fund!)
 

Fullpan,
Send a message to a forum moderator with a copy of the posting you want stuck to the top. That should do it......63bkpkr


Hefty1,
Glad to see you are still out there, how tall is your stack of information now? Enjoy the sunshine wherever you can find it...........63bkpkr
 

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ITS ALL ABOUT PARTICLE SIZE! Yes, there's a bunch of mercury laying out there. Yes, it should cleaned-up. Yes, Clementine lake is contaminated as are
Scott's Flat, Englebright, Lake Wildwood, and others including Combie Res. To my knowledge, all these places have been under a "no sediment dredging" ban
since being listed as impaired with hg. Now, picture a grain of salt. That translates to "less than 63 milimeters particle size of sediment" (hereafter refered to as less than 63) in science talk.
Now when less than 63 contains mercury, it has the POTENTIAL to get into the food chain and "morph" into methylmercury (Mehg) which when ingested by
fish (talking freshwater fish in reservoirs and streams in Ca.) has the POTENTIAL to harm certain categories of humans.
This information was used effectively along with other stuff to ban dredging.
 

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Auburn Journal Jan 31, 2013: "lake mercury removal cost sky-high" Someone did the simple math - 100lbs, 7 million = 70,000 per lb of merc. What we dredgers gave for free in 2000, now cost more than twice as much as gold per oz. to extract. That's what happens when you follow blindly "environmental visionarys" like The Sierra Fund. Ok, do the math on the one million plus lbs still out there!
 

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http://www.waterboards.ca.gov/water_...c_drdg_rpt.pdf
98% Mercury recovered. Free by dredgers of Ca.


[URL]http://nidwater.com/conservation/mercury-removal-project/[/URL]
87% to 93% Mercury recovered. 7-9 Million taxpayers money



The purpose of the Combie Reservoir Sediment and Mercury Removal Project (the Project) is to:
a. Remove sediment that has accumulated in Combie Reservoir since 2003;
b. Remove free elemental mercury using an innovative recovery process from settled and
suspended sediment recovered during the dredging operations; and
c. Develop a Best Management Practice for removal of sediment from Sierra reservoirs with historic mercury contamination.
The Project will dredge sediment from Combie Reservoir using an electric “quiet” dredge while implementing an innovative recovery process to remove elemental mercury from the dredged material, and return clean water to the reservoir. The project will take 3 to 5 years, operating up to nine months per year generally from March to November, each year - weather permitting. The project will remove and treat an estimated 200,000 cubic yards of sediment from the northeastern
08/01/12 5 | P a g e


Taken from page 61 of their report.

Results
Four demonstration tests with the Pegasus Mercury Extraction Equipment were conducted at Combie Reservoir in September and October of 2009. Each independent test was approximately 20 minutes in length.
On September 28, 2009 the test was conducted using material from the drying beds as the source material.
On October 1, 5, and 6th the tests were conducted using the river delta deposit as the source material.

Test 1: The September 28th test processed material that was scooped out of the drying beds by a backhoe and then in 5-gallon buckets with a grout mixer.

Test 2: The October 1st test processed material that was dredged from the river delta on 9/10/09 at the river confluence. This material sat in five-gallon buckets for two weeks prior to the test.

Test 3: The October 5th test processed nine 5-gallon buckets of material that were collected on October 4[SUP]th[/SUP] using buckets and shovels at a point that was 100 ft from the river confluence. This material sat in five gallon buckets for 24 hours prior to the test.

Test 4: The October 6th test processed nine 5-gallon buckets of material that were collected using buckets and shovels at a point that was 200 ft from the river confluence. This material sat in five-gallon buckets for 48 hours prior to the test.


Taken from page 63 of their report.

The total mercury mass balance calculation was complicated by the surprising result that the average concentration of mercury in the samples taken of the head material was less than or equal to the average concentration of mercury in the samples of the tail material for each of the four tests.
In addition, each test was successful at removing elemental liquid mercury from the material that was processed, a range of 187-329 mg of mercury was recovered after each test.

See Table 2. The amount of liquid mercury that was recovered at the end of each test.

Taken from page 64 of their report.

Test 1 was conducted with the drying bed material/Chevreaux waste product, which was mostly silt and clay (86% fines). Test 2 was conducted with the project material (mostly sand, 4% fines) that was collected from the river delta in the area to be dredged. The table below indicates the calculated percent removal of mercury for each test, as well as the estimated head mercury content.
Table 4. The percent mercury removed by Pegasus Mercury Extraction Equipment for each test.


In conclusion the mercury extraction equipment removed approximately 93% of the free elemental mercury in the material that was size fraction > 0.063 mm, sand size.

Approximately 87.223% using test 1, 2, and 4.

WHAT HAPPENED TO TEST 3 AND 4 ???

Discussion
Our understanding of mercury, how it behaves and how to remove it has been broadened as a result of these tests. Primarily, the fact that mercury on the fine/silts and clays is not readily removed by physical separation using a concentrator means that additional treatment of the processed material to remove any suspended solids is important to ensuring that mercury does not re-enter the environment in the turbid effluent. In addition, it appears that the Pegasus Mercury Extraction Equipment removes over 90% of the free elemental mercury bound to sediment that is greater than 0.063 microns, specifically sand.
Mercury removal techniques that can operate on a large scale and can accompany a dredge operation remain a viable, yet developing way, to remove legacy mercury from dredged sediment. Adaptive management and pre and post sampling will remain an integral component of the design and fabrication of the next generation of mercury removal equipment. Transparency and collaboration remain the two most valuable assets of the project team and are critical to its continued success at Combie Reservoir.
The project will take 3 to 5 years, operating up to nine months per year generally from March to November, each year - weather permitting. The project will remove and treat an estimated 200,000 cubic yards of sediment

As to their statement from page 5 of their report.


Taken from page 64 of their report.

Test 1 was conducted with the drying bed material/Chevreaux waste product, which was mostly silt and clay (86% fines). Test 2 was conducted with the project material (mostly sand, 4% fines) that was collected from the river delta in the area to be dredged.
---------------------------------------------------------------------------------------------------------------------

Test 1, Silt and clay…
silt defined as "the sediment deposited by fluvial action against the dam, consisting primarily of loose deposits of sands, gravels and cobbles"
According to the CRC Handbook of Chemistry and Physics (60th Edition), a cubic foot of clay weighs 112 to 162 pounds. A cubic yard would weigh 27 times as much.
3024 to 4374 pounds of clay per cubic yard. Avg, 3699 pounds of clay per cubic yard.


Test 2, Mostly sand…
Dry sand weighs 100 pounds per cubic foot; there are 27 cubic feet in a cubic yard so 2,700 pounds. Wet sand has different weight.
Gravel…
A cubic foot of dry, loose gravel with 1/4" to 2" stones is 105 pounds per cubic foot. So, a cubic yard is that times 27, or 2835 lb. (There are 27 cubic feet in a cubic yard.)
----------------------------------------------------------------------------------------------------------

Test 1, Silt and clay…avg, 3699lbs per cubic yd x 200,000 cubic yds = 739,800,000lbs
Test 2, Mostly sand…Dry 2700lbs per cubic yd x 200,000 cubic yds = 540,000,000lbs
Gravel,dry, loose - ¼”- 2” 2835lbs per cubic yd x 200,000 cubic yds = 567,000,000lbs


Lets use test 2 just for the heck of it…

Test 2, Mostly sand…Dry 2700lbs per cubic yd x 200,000 cubic yds = 540,000,000lbs.


Test Date Time, min Water used (lbs) Material processed (kg) Mercury recovered (g)
2 10/1/2009 20 5180 288 0.3154


20mins to process 288 (kg) of material. 288 (kg) = 634.93lbs.

3 x 20mins = 60mins = 1hr. 3 x 634.93lbs = 1904.79lbs per hr. Material processed.

540,000,000lbs of material to process at 1904.79lbs per hr = 283,495.82 hours.

283,495.82 hours at 24 hours per day = 11,812.33 days.

11,812.33 days at 365 days per yr = 32.36 yrs

_----------------------------------------------------------------------------------------------------------

Mercury recovered (g)

20mins to recover 0.3154(g) of mercury. 0.3154 (g) of mercury = 0.00069534lbs.

3 x 20mins = 60mins = 1 hr. 3 x 0.00069534lbs = 0.00208602lbs of mercury per hr.

50lbs of mercury at 0.00208602lbs per hr = 23,969.09hrs.

23,969.09hrs at 24hrs per day = 998.71 days.

998.71 days at 365 days per yr = 2.74 yrs.



That’s Crazy!!!
 

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Anti-degradation Study 8/12 - (con'td) - This report completed nearly three years after main study in 2009, was last thing required to receive 7 mil in grant money. As Hefty1 points out, the whole thing is filled with mistakes, omissions, lost test results, mishandling of samples, excuses for adverse test results,
60 some pages of "blah, blah" followed, right at the end with damning conclusions. More later, below.
 

Since I have some time before the Super Bowl today, a little more rant.

Anti-deg. Study (cont'd) - Despite Carrie Monohan's (lead scientist on study, and soon to be TSF's (The Sierra Fund) employee as "science advisor") glowing
endorsement of "innovative technology", the Pegasus Earth Sensing Corp. was nothing more than several guys with a knelson bowl on a trailer. Both modern
suction dredges and knelson bowls are not very good at catching particles of gold and merc. if they're attached to say quartz or mud and are less than a grain of salt (less than .063 mm). Four tests were run using four particles sizes and amounts of hg were recorded both going in and coming out of the knelson bowl.
In all cases a chart shows tailings with hg amounts GREATER than going in. "dr. Monohan" tries to explain these "suprising" results by refering to "the nugget
effect" which may or may not be true, I don't know, but in final remarks she admits that "further treatment" of contaminated mud and clay (less than .063 mm) may be called for. Now, Reed Lukens who lives near Combie, tells us that since mud and silt is by far the largest category of particle size "gumming up" lake
Combie, the cutterhead dredge is appropriate to at least the start of recovery ops.
This means that for several months, nothing but mud and silt will be carried to and processed thru the knelson bowl. If this happens, guess what?, there will
be an evergrowing pile of contaminated mud requiring "further treatment"! more, later.
 

The bigger picture - How many of you would, after discovering an oil leak dripping on the driveway, decide to spend the next 3 - 5 years dabbing it up with
towels and rags? Poor analogy but thats the big picture concerning mercury on the Bear River . The Bear is probably the most contaminated of all in the
Sierra. They (people who know!) tell us there are thousands of lbs. of liquid merc. above combie in the river gravel leading up to Rollins lake(also cont.),
and miles upstream, not to mention the tributaries, gulches and tunnels draining hydraulic diggins upstream. Reed has actually seen barrels of merc. in
old tunnels! As a scientist trained in hydrology, dr. Monohan must know that if left alone all that merc. will find its way to combie, yet dredging combie
is the "Best Management Practice"? Please. Common sense tells you to go to the top, go to the source (just like an oil leak) and work from there. Another
case of agenda-driven environmentalism by TSF and their uninformed Benefactors (Sen. Feinstein, did anyone tell you this before asking for Federal
funding?) later, go 49er's.
 

The real thing about mercury is that you cant stop it. But they (the gov,) can use it as a scare tactic...Oh my God!!! its so toxic!!! And the sheepel run with it...lets give them what they want to clean it up!

Where are all the mercury poisoning reports?
 

Forgive me for being a debbie-downer, but the major difference between their plan and the recreational dredger is that they are removing the sediment off site for processing. They are also using centrifuges to seperate matieral that had hg stuck to it. Neither of those things are in the recrea tional suction dredgers standard method of operation. We woukd have to suck all the material into containers and re-process it where its not re-deposited back into the water way.

I agree its a scam purpatrated by sierra fund and it sickens me to think of how much gold they are going to be paid to recover, but thats not the big picture here. The ridicoulous notion that suction dredging is bad for the enviroment us what we should be focusing on here. Is there aby way to use this project to our advantage? If, by showing our support to get thus toxic material out of our water ways, can we gain powerful friends that can help champion our fight against the misguided idea that small scale mining is detrimental to the areas we know and love. Just my two cents
 

I agree it stinks! But the project has sediment removal right it the name...

Certainly wasnt meant to cause discord, like I said just my two cents... food for thought
 

Part 4 of project features and objective 4, both in project description state the "decontaminated material" will be transported off site and sold as aggregate.
 

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