Date: Wed, 3 Apr 1996 12:57:53 -0400
From: Sandy Mathews <Sandy.Mathews@quickmail.llnl.gov>
Subject: Re: Modelling NPS impacts to

Some work on pollutant loadings from highways has been done by CalTrans. 
Unfortunately I tossed the listing of the study names and authors. The
general number for their publication department is (916) 445-3520. 

In addition the Santa Clara Valley Non-point Source Program sponsered a
study completed by Woodward Clyde Consultants in 1992 on metals loadings
from cars.  A 1-page summary of this study is published Watershed
Protection Techniques Vol 1. No. 1 Feb 1994.  Techniques is a generally
useful journel on various water pollution issues.  The study cited that
50% of the loading of Cu, Cd, and Zn in lower San Francisco Bay is from
cars without accounting for tailpipe emmisions.  The authors attempting to
calculate loadings from leaks of gasoline, motor oil, and coolant but it
is noted in Techniques that this data is extremely sketchy and more
research is needed.  Leak rates (at least as noted in the summary) are
percentages of all cars, not volumes leaked per car.  They cite leak rates
of gasoline 0.3, motor oil 0.01, and 1.2 percent of all cars. 

On a different but similar topic the Western States Petroleum Association
and American Petroleum Institute studied runoff from parking lots and
retail gas stations. 

In addtion you might want to check into some of the National Urban Runoff
Program (NURP) studies from the late 1970's. 

Hope this gives you some good leads,

Sandy Mathews                 Lawrence Livermore National Laboratory
mathews6@llnl.gov             P.O. Box 808, L-629
(510) 423-6679                Livermore CA 94551