With a slight editorial modification, your last proposal is the best:
        have more cyclists collect discarded weights.
And we would be healthier too!

Bob Hilty
Tyco Electronics

> -----Original Message-----
> From: Brian Ellis [SMTP:[log in to unmask]]
> Sent: Friday, May 04, 2001 8:14 AM
> To:   [log in to unmask]
> Subject:      Re: [LF] Lead in Ammunition; EPA TRI ruling
>
> Bruce
>
> Let us imagine that your friend collects just 1% of all the weights cast
> in the SF area. That means that the total is in the region of 1.5
> tonnes. I don't have a hydrological map of SF bay handy, but I imagine
> we are talking about at least 100 km3 of water, probably a lot more,
> i.e. 10^11 tonnes. Just for the sake of argument, let us assume the lead
> from those weights all dissolves instantaneously into the bay. Result: a
> very small fraction of ppb, nearly ppt. However, it will be even less a)
> because the water in the bay is not static because it is being
> constantly replaced as water flows into the bay from land sources
> (including treated waste water) and by tidal flushing; b) lead will not
> dissolve instantaneously ; c) the solubility of lead in sea water is
> lower than in pure water (cf lead artefacts recovered from 3000 year old
> shipwrecks in the Mediterranean). Even if my original hypothetical
> estimations are way out, there is plenty of margin to show that there is
> absolutely no risk of SF Bay becoming sterile because of this source. In
> reality, the geology of the region is probably such that the number of
> tonnes of lead washed down in alluvium during the rains will be many
> times all the lead dropped off wheels in the whole of California.
>
> Let's keep a sense of proportion.
>
> However, there are ways of mitigating your hypothetical problem: a)
> force tyre manufacturers to make their products so that less wheel
> balancing is required; b) force weight manufacturers to redesign the
> clips, so that the weights don't come off; c) replace the lead by tin
> (see http://www.itri.co.uk/wweights.htm ) and d) have more cyclists
> collect discarded weights.
>
> Brian
>
> --------------------------------------------------------------------------
> -------
> Leadfee Mail List provided as a free service by IPC using LISTSERV 1.8d
> To unsubscribe, send a message to [log in to unmask] with following text in
> the BODY (NOT the subject field): SIGNOFF Leadfree
> To temporarily stop delivery of Leadree for vacation breaks send: SET
> Leadfree NOMAIL
> Search previous postings at: www.ipc.org > On-Line Resources & Databases >
> E-mail Archives
> Please visit IPC web site (http://www.ipc.org/html/forum.htm) for
> additional
> information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700
> ext.5315
> --------------------------------------------------------------------------
> -------

---------------------------------------------------------------------------------
Leadfee Mail List provided as a free service by IPC using LISTSERV 1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Leadfree
To temporarily stop delivery of Leadree for vacation breaks send: SET Leadfree NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
---------------------------------------------------------------------------------