I have some peripheral experience of these issues relating to abandoned
mine discharges. One of the key factors against the use of wetlands is
the required surface footprint.
Keith

-----Original Message-----
From: mining-history [mailto:[log in to unmask]] On Behalf Of
Richard-PC
Sent: 10 March 2010 09:46 AM
To: [log in to unmask]
Subject: Re: History of AMD Remediation Technology

Justin,

I have no experience of the situation in the USA but have worked with
both 
chemical and passive systems with factory effluents in the UK.  I think
the 
thought process would go along he following lines:

Whatever technology is used it is normally in response to an existing 
legislative requirement or the possibility of future litigation.  Some 
decades ago, the problem may only have been addressed after the mine had

closed and would have been a 'crisis management' response requiring 
immediate action.  Chemical treatment offers a sure, robust method of 
remediation which can cope with quite large variations of flow, metal 
content, presence of different metals, suspended solids etc.
Environmental 
factors such as drought, freezing and the like can be built in to the 
design.  Dredging of residues can be reduced to a planned maintenance
regime 
and can be done in a spatially restricted area.  Residue treatment such
as 
dewatering is manageable using proven techniques. In short it provides a

sure-fire silver bullet and the on-going costs can be met by future 
generations of management.  Thirty or forty years ago it was seen as the

method of choice for treating effluents of all levels of contamination
or 
volume.

Wetland technology is likely to be much more sensitive to all of these 
factors, although it has the advantage of requiring less day to day 
maintenance.  Thirty years or so ago it was seen as a great way to clean
up 
large amounts of only slightly contaminated effluent.

However, I think that you have to put the questions into the context of
the 
times and the people involved.  Mining and industrial companies usually
have 
plenty of engineers and chemists around who would see chemical processes
as 
an obvious choice - certainly several decades ago.  Constructed wetlands

would have been seen as requiring external specialists such as botanists
for 
both implementation and maintenance.  Furthermore, there is always a 
reluctance to get involved with unproven technology or be a pioneer, 
particularly where regulatory or liability issues are concerned - unless
of 
course there are compelling reasons to the contrary.  Who would want to
be 
first when proven chemical techniques were already available in other 
industries such as smelting, metal finishing and a whole host of
processes 
producing acid effluents?

Consider also the structure of mining companies, where funding decisions
on 
technology are made by off-site directors who rely on their own in-house

technical specialists.  If they already have a technology working at one

site, it generally gets replicated elsewhere.

I suspect that you are already aware of these arguments.  I believe the 
answer to your question lies in the attitudes of industrial managements 
towards risks, particularly where the consequences are crucial and costs
are 
less important.   However, I suspect that finding documentary proof of
this 
will be difficult.  At the risk of digression, I can only point to a
lecture 
I attended at one of the IMM's conferences in the 1970s.  It dealt with 
sinter plants, all of the same overall design, but in the space of a
decade 
or so these had doubled in size and then doubled again. The lecturer 
bemoaned the plight of sinter plant manufacturers which did not have a 
demonstration plant available of the latest size or at least the
generation 
before that.  It was clear that the smelting industry would only
purchase 
from those who had and a list of SPMs who had gone out of business for
this 
reason alone was presented.  This seemed to echo what I already knew
about 
management's view towards risk and new technology.  Where new
technologies 
were implemented, these were always in response to a compelling need and

where existing technology did not provide the answer.

Regards

Richard Smith



----- Original Message ----- 
From: "Justin Page" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, March 09, 2010 5:48 PM
Subject: History of AMD Remediation Technology


> Colleagues,
>
> I am writing to seek guidance (references, contacts, informal
knowledge) 
> on
> the history of remediation technologies for Acid Mine Drainage in the
US 
> and
> Canada.
>
> The purpose of our research is to identify historical factors that
have
> influenced industry's adoption of active technologies (chemical
treatment)
> over passive technologies (constructed wetlands) - or rather the
reticence
> of industry to adopt passive technologies - for the remediation of
AMD.
>
> Any references, contacts or information that you may have about the
> historical development of remediation technologies - including
regulatory,
> economic, political, social, or other influencing factors - would be a

> great
> help.
>
> Thank you in advance,
>
> Justin
>
> PS - Our working hypothesis is that active and passive technologies
are
> associated with different technological paradigms, and that there are
> particular factors that "lock in" one paradigm over the other.  We
> hypothesize that industry's technological paradigm with respect to
> remediation is one of "environmental engineering," involving
commitments 
> to
> certainty, control and prediction.  In contrast, we hypothesize that 
> passive
> remediation is connected to a paradigm of "ecological engineering,"
> involving commitments to openness, flexibility and working with,
rather 
> than
> against, nature.  We are looking for the factors that lock in the
first 
> over
> the second paradigm.
>
>
>
> --
> Justin Page
>
> PhD Candidate
> Department of Sociology,
> University of British Columbia
>
> Sessional Lecturer
> Department of Sociology and Anthropology
> Simon Fraser University
>
> Research Assistant
> Translational Genomics Research Group
> The W. Maurice Young Centre for Applied Ethics
> http://www.tgrg-ubc.org 

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