[env-trinity] FW: Proposed Suction Dredging Regs

[Brian Hill]

To env-trinity/Glen Spain:

 

 

 

Below is a letter to Mark Stopher from Dave MacCracken who was a participant
in the USGS study Mercury contamination in California's South Yuba River,
available at:  http://www.usgs.gov/newsroom/article.asp?ID=2686.

 

Glen H. Spain said in a previous email on this list that "[w]hile the dredge
might catch some otherwise dormant and sequestered subsurface mercury, it
also stirs it up and methylates the rest (and likely a lot more than it
catches), thus creating the most water soluble (and toxic to humans and
fish) chemical compounds of mercury known",  but Wikipedia says that
colloidal mercury in nature is not sequestered or dormant, rather,
'[m]ethylmercury is formed from inorganic mercury by the action of anaerobic
organisms <http://en.wikipedia.org/wiki/Anaerobic_organism>  that live in
aquatic systems including lakes <http://en.wikipedia.org/wiki/Lake> , rivers
<http://en.wikipedia.org/wiki/River> , wetlands
<http://en.wikipedia.org/wiki/Wetland> , sediments
<http://en.wikipedia.org/wiki/Sediment> , soils
<http://en.wikipedia.org/wiki/Soil>  and the open ocean
<http://en.wikipedia.org/wiki/Ocean> .[5]
<http://en.wikipedia.org/wiki/Methylmercury#cite_note-4>  This methylation
process converts inorganic mercury to methylmercury in the natural
environment."  So colloidal mercury naturally converts to methylmercury and
enters the food chain as a natural process.  Thus, mercury in any form in
our waterways poisons all life exposed to it, sooner or later.    This is
why, according to the testimony below, that suction dredges are employed to
remove mercury from the Combie Reservoir which stores drinking water for
humans.  

 

Lastly, Spain's comment that "[w]hile the dredge might catch some otherwise
dormant and sequestered subsurface mercury, it also stirs it up and
methylates the rest (and likely a lot more than it catches)" seems
questionable when one considers MacCracken's claim, based on his
participation in the studies relied on by Spain and his own participation in
these studies, that 95-98% of the mercury is removed from waterways with
suction dredges.

 

As for suction dredging, "disturbing or destroying intra-gravel eggs".  Fish
and Game dredging regulations carefully prevent dredging in spawning areas
and during spawning seasons.

 

Are there studies documenting "disrupting noises affecting fish behavior",
because the sound of dredge motors cannot be heard underwater, at least by
humans, and there is no shortage of fish wherever dredging is taking place.

 

Doesn't it therefore seem practical to use suction dredges to remove 95-98%
of the mercury from our waterways so that the colloidal mercury does not
continuously convert to methyl mercury?  There seems to be enough scientific
documentation available to develop best practices standards for river
restoration and for suction dredge mining if all stakeholders can meet and
develop consensus based on the best science and technology available.

 

Brian Hill

 

____________________________________________________________________________
______________

 

Pro-Mack Mining

Underwater Mining Specialists

 

Mark Stopher

Acting Regional Manager

California Department of Fish and Game

601 Locust Street

Redding, CA 96001

6 March 2010

 

Dear Mr. Stopher:

 

I understand that a presentation was made at the most recent suction dredge
PAC

meeting concerning a mercury clean-up pilot project that I personally was
involved with

on the South Fork of the Yuba River, Malakoff Diggins, Humbug during 2007
and the fall

of 2008. As I am at somewhat of a disadvantage of not being able to study
any final

findings concerning that project [would someone please provide a link to
these findings?],

and it sounds to me like some of the results are being

taken out of the proper context, please allow me to go on record in the
ongoing suction

dredge CEQA process with a factual basis concerning the project:

 

I was first contacted about the project on 23 August 2008 by Matthew Wetter
of Tetra

Tech EM Inc., which is an environmental services engineering company based
at

10860 Gold Center Drive, Suite 200 | Rancho Cordova, CA 95670 |
www.tetratech.com.

Mr. Wetter e-mailed me that Tetra Tech was "working with Dave Lawler at the
BLM on a

mercury removal treatability study," and was interested in contracting the
services of my

company, Pro-Mack Mining, to provide underwater excavation (dredging work)
for the

project. Mr. Wetter asked me to provide a bid for our services. Tetra Tech
also provided

the following information:

 

"Contract Officer Representative (COR): David Lawler is the designated

Contracting Officer Representative (COR) for the project. Mr. Lawler is
located in

the California State Office. Mr. Lawler can be contacted at Bureau of Land

Management, CASO, Attn: Dave Lawler (CA-920), 2800 Cottage Way Ste. W-

1834, And Sacramento, CA 95825-1886, Cell phone: (916) 425-3740"

 

In order to gain a better understanding of the project and make a proper
bid, I followed

up in a telephone conversation with Mr. David Lawler. In turn, Mr. Lawler
sent me the

following explanation:

 

BPS Project Title: HUMBUG CK-SOUTH YUBA PILOT MERCURY CLEANUP

PROJECT

BPS Project Number : (#36234)

 

Description: The Humbug Creek Project site is located at the confluence of
the

South Yuba River and Humbug Creek on unpatented BLM administered land within

the North Bloomfield Mining District. Project proposes to remove a mercury
"hot

spot" consisting of several hundred pounds of elemental mercury contained
within

the Humbug Creek Delta, located at the confluence of Humbug Creek and South

Fork Yuba River. Thousands of pounds of elemental mercury were lost from

historic placer gold sluice box systems at the North Bloomfield Hydraulic
gold

mining operations during the 1850's-1880's period. Significant amounts of

elemental and amalgamated mercury were than deposited within a hydraulic

tailings dam at the confluence of Humbug Creek and South Fork Yuba River.
The

tailings dam has subsequently been destroyed during a series of 100+ year
flood

events on the South Yuba, allowing mercury contaminated sediment to
discharge

seasonally downstream. BLM manages 7 miles of contiguous watershed on the

South Yuba from 1/2 mile upstream from Humbug Creek to Purdon Crossing. This

site represents an excellent pilot - mercury "hot spot" removal project,
since

significant watershed impacts have occurred to the BLM-managed portion

immediately downstream from the hydraulic mine. Project proposes to use

modified suction dredge equipment - combined with conventional placer gold

recovery equipment/technology to recover large quantities of elemental
mercury

without undue degradation or impacts to the watershed.

 

Geographic Description: T.17N, R.9E.,S.14, ,MDBM, NEVADA CO.,

CALIFORNIA (SOUTH YUBA RIVER WATERSHED)

 

Benefits: The Humbug Creek Delta site is one of the known elemental mercury

"hot spots" known in the Sierra Nevada region with elevated mercury levels
in

water and sediment. Removal of high concentrations of elemental mercury

contained in mercury-contaminated stream and river sediments at this site
will

eliminate a pollution "point source of discharge" of hazardous materials
under the

Clean Water Act and reduce downstream discharge within the South Yuba River

watershed. The California State Water Control Board and other regulatory

agencies require that BLM mandate significant reductions in mercury loads
from its

managed lands within the Sacramento River watershed - Bay Delta region,
under

its existing basin plan.

 

Feasibility: This site is one of BLM's emerging priority AML 1010 sites for
pilot

cleanup. Project implementation will include use of modified suction dredge

equipment - combined with a conventional placer gold recovery equipment and

technology to recover large quantities of elemental mercury without undue

significant degradation or impact to the watershed. During FY99-03, USGS

technical specialists have previously collected water, sediment, and biota
samples

from selected sites within this watershed. During FY06, USGS technical
specialists

and watershed stakeholders (e.g. Trout Unlimited, SYRCL) will coordinate on
preremediation

sampling of water, sediment, and biota at this specific site. BLM

coordinators and contractor(s) will also compile all required CERCLA and
NEPA related

environmental documents. Testing of pilot mercury removal methods will

also occur. During FY07, BLM coordinators and contractor(s) will undertake
pilot

cleanup of fluvial bedload areas containing elemental mercury
concentrations.

During FY08-09, post-remediation monitoring will be undertaken to assess the

watershed benefits of mercury "hot spot" removal.

 

Support: There is widespread support from interagency Federal partners

(USFS,ACE,EPA), State Partners (DOC AMLU,CWQCB,RWQCB, CA Fish&Game,

Public Health), County Partners (Dept. Envtl Health) and various watershed

stakeholders (Trout Unlimited, NCRCD,SYRCL, Yuba Watershed Institute).Trout

Unlimited has been working on AML partnerships efforts in Utah (American
Fork) -

subsequent remediation actions have effectively reduced toxic metal source

loading to downstream watershed environments. Trout Unlimited volunteers can

potentially assist with collecting additional macroinvertebrates and fish
from the

project site for bioassessment purposes. The California State Water
Resources

Control Board (CA-SWRB) is highly interested in removal of elemental mercury

"hot spots" in priority watersheds. The South Yuba is a 303(d) listed
impaired water

body for mercury. The SWRCB will to match funds with BLM on this cleanup

project.

 

Project Objectives: To develop portable suction dredging equipment that will

effectively recover elemental mercury from submerged sediments.

Subsequently, Pro-Mack's involvement in the project (hereafter referred to
as "BLM

project") was contracted by Tetra Tech. This evolved into several site
visits and a trial

run during the fall of 2007, using a standard 3-inch Keene dredge. The trial
run was

mainly to work out how we would do the project during 2008 using an 8-inch
dredge.

During one of the site visits, I had a personal opportunity to engage in a
substantial

discussion with Mr. Charlie Alpers, USGS Research Chemist, who I understand
is a

leading authority on the subject of mercury. Mr. Alpers was directly
involved with this

BLM project. As I am an expert in heavy metals recovery, I found Mr. Alpers
very

interesting. During our conversation, Mr. Alpers instructed me on several
points which

he believed were important in context to the BLM project objective to
determine if normal

suction dredges can properly be used to recover mercury from established
mercury

waste sites. Here are a few of the points Mr. Alpers made (according to my

understanding, in my own words):

 

1) The nature of mercury as an element allows it to break down into such
small

particles (perhaps smaller than particles), that they can become permanently

suspended in water. Mr. Alpers described this as "colloidal." This, similar
to the

salt in sea water.

 

2) Through different kinds of physical and biological activity, elemental
mercury

can be transformed into different forms and migrate away from the original
location

(point source).

 

3) Mr. Alpers and the other USGS scientists involved in the BLM project made
it

abundantly clear that science has shown that very small particles of mercury
have

a strong attraction to very, very small particles of light sediment.

 

4) Mr. Alpers told me that modern science now has the equipment to measure
the

presence of mercury in nearly every substance known to man. He told me
mercury

is present nearly everywhere. He said the instruments at his disposal would
detect

mercury in any of the soils or riverbeds in California.

 

In view of these revelations from Mr. Alpers, it seemed clear to me without
going any

further that standard suction dredges could not be used to remove 100% of
the mercury

from established mercury waste sites. Standard suction dredges (use of
gravity

separation recovery systems) will be effective at removing all or most of
the elemental

mercury down to a certain size fraction. Pro-Mack (and Keene Engineering)
has

developed advanced gravity recovery systems on suction dredges that will
recover

elemental mercury effectively down to any size fraction within the visible
range.

But when you start getting down to capturing colloidal (mercury which has
become part

of the water), or capturing extremely fine sediments with mercury attached
to them, it is

clear that gravity separation alone (such as the Nelson Concentrator) is not
the answer

for 100% results.

 

Please keep in mind that this explanation is in context to the BLM Project

Objective, which was to determine whether or not standard suction dredges
can

be used to effectively recover the mercury from an established mercury waste
site

located at the bottom of a flowing waterway.

 

Sometime during the summer of 2008, the California Water Quality Control
Board made

a formal objection to BLM and USGS. In view of the 98% recovery results (of
mercury

from an established mercury waste site in another location) by Mr. Humphreys
using a 4-

inch dredge, the Water Board did not want us to use an 8-inch dredge at the
confluence

of the South Yuba River and Humbug Creek. While I was not privy to all the

communications involved, I was informed by Mr. Wetter that the potential of
a 2% loss of

mercury into the water column might be considered a water quality violation
by the State

of California.

 

Consequently, BLM formally revised the purpose of the project to the
following (please

see attached Revised Scope of Work for agreement between the USGS and the
BLM

which is dated June 27, 2008):

 

Purpose:

Because dredge operators have collected and recovered large amounts of Hg
from

the South Yuba River near Humbug Creek, the BLM wishes to remove and recover

these Hg-contaminated sediments, thus removing a potential environmental
hazard

from the ecosystem. However, it is unknown what impact the removal process
will

have in the immediate vicinity of the dredge operation or downstream. The
BLM

initially proposed to remove the Hg from the confluence using a suction
dredge.

Although suction dredging has been shown to recover as much as 98% of the

mercury from contaminated river sediments, qualitative evidence suggests
that the

dredging may, through "flouring" of the Hg during the suction dredging,
actually

enhance Hg transport and reactivity and ultimately increase Hg uptake in

downstream biota (Humphreys, 2005). Before suction dredging or any other

removal technique can be used, the hotspot will need to be characterized to

determine the potential impact of the removal on downstream environments.

Since dredging within the active waterway was no longer going to be part of
the project,

another site visit was scheduled so that we could locate a place(es) to take
samples

outside of the active waterway. Matt Wetter may have a record of who
participated in

that visit to the site. I was there, along with several participants from
the USGS. We

found a gravel bar out in the S. Yuba River that was located near the
confluence of

Humbug Creek. We also found some dry riverbed just downstream from Humbug

Creek. As dredging was not going to be allowed, these were pretty-much the
only two

remaining options to obtain samples. We decided to sample the gravel bar
(located out

in the river) first, and then follow with the riverbed gravels alongside the
river.

As I had originally bid the project to provide an 8-inch dredge, and we were
not going to

be able to use that, Matt Wetter asked me if there was some other type of
gear that Pro-

Mack could provide to assist with the project. So my Pro-Mack team went to
work in our

shop to create a suction excavation system that would contain all of the
material, using

recirculated water, so that there would be zero discharge back into the
active waterway.

This system used the same principle as a normal dredge to create suction at
the nozzle.

But this was different because water and excavated material were pumped into
a holding

tank, and the water was then pumped out of the holding tank to provide
suction to the

nozzle. We were using the same water over and over again within a closed
system to

create our suction-power at the nozzle (please see attached images).
[attachment provided if requested]

 

Because Mr. Alpers voiced concern about colloidal mercury, and very small
particles of

mercury that attach themselves to sediment, Pro-Mack devised a suction
recovery

system that would capture 100% of the sediment, along with 100% of the water
used in

the excavation process. I ran this idea by the BLM project team in a phone
conference,

and the participants (USGS, BLM, Tetra Tech) expressed interest and
encouragement.

My understanding is that BLM (Dave Lawler) ran the idea by the Water Board
and they

decided to send Rick Humphreys out to observe our project. He was present
when we

operated Pro-Mack's self-contained suction system, and Mr. Humphreys, along
with

everyone else present, agreed that we made no discharge into the river using
our self

contained suction system.

 

To my knowledge, this is the only system -concept in existence that will
provide 100%

recovery of hazardous materials in all forms from waste sites (mercury or
otherwise),

either above or below the water.

 

Here follow some very important observations which should not be ignored:

1) The gravel we were excavating from the bar out in the South Yuba River
was

above the river during late fall flows. They will be underwater during
winter flows,

or at least during storm events. This was mostly loose gravel. It was not a
hardpacked

streambed; it was not compacted or armored. This means that those

gravels likely get swept downstream during storm events; especially large
storm

events. Therefore, any mercury recovery we obtained within our closed system

is the same mercury that will be washed down the river system during storm

events. Since our excavation was small in comparison to the whole area of
the

South Yuba that is identified as a waste site, it is reasonable to assume
that huge

volumes of mercury are moving downstream during storm events.

 

2) This was just a trial run of a closed circuit suction excavation system
to

determine if it would work. It was only the first phase on a small scale.
Tetra

Tech, BLM and USGS agreed to analyze samples of the collected water to see
if

our closed system will recover and concentrate mercury; specifically the
very fine

mercury that they are so concerned about. Since it was just a
beginning-test, I

don't believe that anyone kept close track of the volume of gravel that we

excavated. More importantly, we did not measure how many times the same

water was recirculated to excavate the waste materials.

 

While I have not seen the test results on our recirculated water, I
understand that

Mr. Alpers stated in the recent PAC meeting that the mercury levels were
very

high. This is good. It means our system worked very well to recover and

concentrate the small particles of mercury from the waste site which Mr.
Alpers

and other scientists are concerned about; particles so fine in size that no
gravity

system alone can be expected to provide adequate recovery if 100% results
are

desired.

 

Note: Before using our closed suction system, after carefully sanitizing the
tank

(with a solution which USGS brought along specifically for that purpose), we

carefully filled it with water from the South Yuba River. I am certain that
the

USGS team captured and analyzed water samples from the South Yuba to

create a baseline. Therefore, any increase in mercury in the water from our

closed system will be mercury that we recovered and concentrated from the

waste material at the site. The higher the concentration of mercury within
our

closed system, the more mercury we removed from the environment!

3) In a closed system such as this, the longer we operate it in the waste
site, the

more times the very same water is exposed to the waste, and the more

concentrated the mercury will become in the water. We ran the system for

perhaps two hours or longer. The pump we used produces 350 gallons per

minute. This means the water was recirculated through the waste material
more

than 100 times. I understand that during the PAC meeting, Mr. Alpers
reported

that suspended sediment and mercury was present in the water from our closed

test seven days afterwards. That is exactly what you would expect to see
with

recirculated water that was used 100+ times to excavate mercury-contaminated

material!

 

4) Very important: While anti-mining activists are sure to try, the results
of this

test (concentration of mercury in the water used within our closed system)
cannot

be correlated or compared to normal suction dredging in California's
waterways.

Here is why:

 

A) First of all, we were doing the project in an established mercury hot

spot. Please read David Lawler's BPS Project description above. This

site is so contaminated, the California Water Board refused to allow BLM

and USGS to operate suction dredge there for the BLM project. Even

while we were conducting our tests, Rich Humphreys was swimming

around the area with mask and snorkel and finding visible mercury on the

bedrock. We were panning mercury from the bedrock just upstream from

where we performed this testing. This place is loaded with mercury

contamination!

 

It would be grossly unfair to compare the average stretch of California

waterway to this established waste site where "Thousands of pounds of

elemental mercury were lost from historic placer gold sluice box systems"

(BPS Project description).

 

B) To my knowledge, California's average waterways have not been

quantified as to the amount of mercury which exists in them. If present at

all, the amount of mercury is sure to vary from one location to the next.

According to Mr. Alpers, some level of mercury can be located anywhere

(everywhere). Therefore, for the purpose of dredge regulation, we

should be concerned with hazardous levels of mercury. We should

not be comparing normal suction dredge activity to an isolated extreme

condition! For the purpose of dredge regulation, it would be highly

indefensible to use the results of a toxic cleanup test as a baseline

average for all waterways in California!

 

C) The water from our closed system that was recirculated through

mercury waste at least 100 times cannot be compared to the water

discharge from a normal dredging system in an average waterway. Our

closed system exposed the same water over and over to pre-established

mercury waste (continuous exposure for hours). The water flowing

through a normal dredge will have been exposed to gravel only once (for

several seconds), likely in a location which does not contain hazardous

levels of mercury in the first place. Any attempt to compare normal

dredging conditions with a concentrated solution used to clean up a

heavily contaminated site would be completely lacking in intellectual

integrity.

 

D) Our closed system design appears to have confirmed Mr. Alper's (and

the California Water Board's) concerns about potential losses of fine

particles of mercury if standard suction dredges are used to clean up

established mercury waste sites. That is, if California's policy is to

proceed with mercury recovery only if 100% results can be obtained.

We could argue over whether or not the dredge system is causing

flouring, or if the mercury is already present there in a form that is too

small to recover using gravity methods. But it doesn't really matter. If our

closed system concentrated suspended mercury in the water, it seems

reasonable that recovery systems (used in established waste sites) must

be developed that contain all of the water which is used during the

excavation and gravity separation process. Then the water will need to

be treated.

 

E) Because the mercury that is not removed from active river systems is

sure to migrate downstream, and we have already developed the

prototype of a closed excavation system, I would encourage the various

State and federal agencies to continue the important work which BLM and

USGS has been doing in this area. I would be pleased to participate, as

long as the process is intended to clean up California's waterways, rather

than put suction dredgers out of business.

 

F) Anyone who would attempt to use the important results we have

obtained in a very serious waste site to reflect upon conditions in a

normal dredging setting is probably more motivated by political gain, than

in cleaning up California's waterways.

 

The truth is that suction dredging is the only workable way of discovering

where the mercury hot spots are located in California's waterways.

According to the BLM BPS Project description above, it was suction

dredgers who discovered the waste site at the South Yuba River and

Humbug Creek. And it will require suction dredges (modified into closed

systems) to remove the contamination. Mercury that is not removed will

haunt California for the foreseeable future.

 

This very same scenario could be playing out in other locations. Suction

dredgers are the solution to this problem. Shutting them down because

mercury is proven to exist within isolated locations would be

counterproductive. This is because Mother Nature will just keep

pounding that mercury down into more-broadly distributed, smaller and

smaller particles while we do absolutely nothing about it.

 

5) Most important: Based upon all of the results we obtained in this BLM

project, along with all of the concerns expressed by BLM, USGS, DFG,
California

tribes and environmental organizations, there may be some serious problems

with the Nevada Irrigation District's (NID) plan to clear toxic Gold Rush
mercury

from Combie Reservoir (they also intend to use a suction dredge).

According to the press release at

http://www.theunion.com/article/20100227/NEWS/100229808/1066
<http://www.theunion.com/article/20100227/NEWS/100229808/1066&ParentProfil>
&ParentProfil

e=1053:

 

"NID had Canadian firm Pegasus Earth Sensing Corp. demonstrate the system

last fall and managed to extract six grams of mercury per ton of sediment

dredged from the bottom of the reservoir. NID routinely dredges the
reservoir to

extract silt and keep water capacity as high as possible for customers."

"Pegasus designed their centrifuge to extract gold from ancient river rock,
but

company officials found it did a better job of trapping mercury, according
to

Monohan."

 

A centrifuge is a gravity separation device. And while very effective at

concentrating heavy metal particles down to a certain size, it will not be
effective

at recovering the colloidal mercury which Mr. Alpers is concerned about.
Even

worse, a centrifuge is designed specifically to discharge (as tailings) the
very fine

particles of light sediment which USGS scientists are so concerned about

(because micro-particles of mercury attach to them).

 

Perhaps the largest concern should be that all of the colloidal mercury and
fine

sediment which is stirred up in the water during the excavation process
("NID

routinely dredges the reservoir to extract silt and keep water capacity as
high as

possible for customers.") will most certainly be creating a water quality
violation

of huge proportions -- for all the reasons which are being expressed by PAC

participants in the suction dredge CEQA process. The NID Project description

on line shows a diagram of the planned dredge system. More than just a
suction

dredge, the NID dredge will employ a cutter head at the nozzle (see

http://evereadymarineservices.com/downloads/Eveready%20Marine%20Services

%204.pdf ). A cutter head is a powerful grinding machine that is designed to

break up solids and force oversized material out of the way. A cutter head
will

create enormous disturbance down in the contaminated sediments.

Consequently, some substantial portion of the disturbed water and light

sediments within the contaminated material will be greatly disturbed, pushed
out

of the way and not be sucked up as dredged material.

 

Reading more about the NID project at

http://www2.newsvirginian.com/wnv/news/local/article/old_technology_new_solu
ti

on/42961/961/

"Tim Crough, assistant general manager with the Nevada Irrigation District,
who

is overseeing the project, said the district wants to remove the mercury in
its

elemental stage, where it is less harmful." He said, "Knelson Concentrators'

mercury-removal process combines traditional dredging technology with a
"spin"

process, using the company's Knelson Mercury Recovery Concentrator, to

separate and remove the mercury from the sediment and out of the water. "If
we

can remove 95 percent of it, which the Knelson Concentrator is expected to

do, we can free up that much of the river system from having the
contamination

of methyl mercury," Crough said.

http://www.sacbee.com/2009/03/24/1723627/nevada-irrigation-districtplans.

html:

 

"Tim Crough, the district's assistant general manager, said the Combie
project

would combine dredging with a centrifuge process to "spin" the mercury out
of

water extracted from the lake. '"It's a pretty novel approach," said Charles

Alpers, a research chemist with the U.S. Geological Survey in Sacramento

and a consultant for the project."'

 

"The elemental mercury that would be removed, according to Ryan Jones, a

Knelson Concentrators representative, is relatively simple to recover and

inexpensive when using the company's device. '"The important thing is to get

the elemental mercury out of the material so that it can't convert to methyl

mercury," ' Jones said."

 

The press release goes on to say: "The consultant (Carrie Monohan) is also

on the staff of the Sierra Fund in Nevada City, which has been educating

Californians about the mountain range's toxic mining past in recent years."

At http://www.conawayranch.com/content/mercury-rising

"Elizabeth "Izzy" Martin, CEO of the Sierra Fund, is quoted as saying '"The

state's rules are forcing Sacramento into that mode. They're a hundred miles

down from the problem and trying to filter it out. Sacramento would very
much

like to come up here and clean up the mercury because they think it will

probably be cheaper to clean up four hundred pounds of mercury up here

than it will be to filter out two pounds of mercury down there."'

 

While I personally would not disagree with these statements, there appears
to be

two different standards being applied here. The Water Board is objecting to
normal

suction dredges because Rick Humphries measured a 2% loss of mercury from a

standard 4-inch dredge. Mr. Alpers and the Sierra Fund are objecting to
normal

suction dredges because of the potential of not recovering colloidal mercury
and

extremely fine particles of mercury that have evolved out of the elemental
stage

and attach themselves to fine sediments which can remain suspended in water
for

long periods of time.

 

Yet both Mr. Alpers and the Sierra Fund are directly involved as consultants

in this NID project which is only targeting 95% of the elemental mercury.

How can this be?

 

DFG can do the math on six grams of mercury per ton of sediment. There is no

doubt that this should be classed as a mercury hot spot, hazardous waste
site.

That amount of mercury will exceed the average amount of mercury in
California's

rivers by thousands or millions of times. Yet the Sierra Fund , who is
working so

hard to put suction dredgers out of business in sections of California
waterways

where hazardous levels of mercury are not even present, is completely
ignoring the

science which has been developed in the BLM project, the very science which
they

are now attempting to use against suction dredgers.

 

All you need to do is look at Charles Alper's data on the amount of mercury
in the

water that we concentrated in Pro-Mack's closed tank system, and you will
know

that the NID project and Sierra Fund are stirring up the very same kind of

contaminated water and sediments at the bottom of the Combie Reservoir with
the

use of a cutter head devise (powerful grinding machine) -- which is a source
of

drinking water for Californians.

 

Mr. Alpers and the Sierra Fund cannot have it both ways. If it beneficial
for NID (at

a cost of $8+ million) to recover 95% of the elemental mercury from an
established

waste site within a drinking water supply, while stirring up and spreading
around

particles of mercury which are too small to recover, then it is also
beneficial to have

suction dredgers recovering 98% of any mercury they happen to encounter
while

assisting the State to locate new hot spots (at no cost to the State or
federal

governments).

 

The CEQA process is designed to flush out real problems using the best
available

science. There is supposed to be integrity in the process. If you are
allowing

gravity separation equipment to process mercury from a mercury hot spot
inside of

a reservoir, then you certainly cannot object to gravity concentration
technology

being used by suction dredgers in areas which are not known to contain any

hazardous levels of mercury.

 

I hope this helps place Mr. Alper's test results in a more balanced
perspective, and

would be pleased to provide more information upon request.

 

Sincerely,

Dave McCracken

27 Davis Road, Happy Camp, California 96039

(530) 313-5378 Fax: (530) 493-2095 www.promackmining.com

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