Environmental Engineering Reference
In-Depth Information
Table 2 Some potential local and regional sources of mercury contamination to the San Francisco
Estuary from historical and modern human activity
Industry
Notes
Chloralkali a
Chlorine and caustic soda produced by the Castner-Kellner
process (mercury cell) at facilities in Oakland, CA (1919-1957)
and Pittsburgh, CA (1917-1973). Contamination occurred
potentially via wastewater, spills, and air.
Petrochemical b
Major center of refineries 1900-present. Mean concentration of
mercury in CA crude oil is 0.011
µ
g g −1 , but some reported
values exceed 1
µ
g g −1 . Although historically CA was self-reli
ant in petroleum supplies, recent years (1996-present) show an
increase in foreign imports. Fate of mercury in refining process
not well known.
Medical waste
Facility operated in East Oakland 1982-2001. Large source of
incineration c
mercury to atmosphere during that time (800 kg yr −1 in 1996).
Wastewater d
Mercury used as slimicide in wastewater treatment. Wastewater
also contains mercury lost from hospitals, dental offices, and
industrial waste. Total amount unknown.
Gold mining e
Gold mining began in mid-19th century and continued into the
20th century; 12 M kg mercury used in hydraulic-placer
mining, ore-processing at hard rock mines, and drift mines and
dredging operations in CA, with 4.5 M kg mercury lost to the
environment from hydraulic placer mines, and 1.4 M kg lost at
hard rock mines.
Other sources f
Mercury released to the atmosphere from cement manufacturing
plants, carbon black production facilities, and waste burning.
Mercury disposal in landfills of electrical devices (the principal
use of mercury in the 20th century), including batteries,
switches, and lamps, likely represents a primary repository of
mercury in the region.
Antifouling paint g
Use of mercury in antifouling paints in the estuary dates at least
to early 20th century. Between 1940 and 1970, approximately
0.04 M kg mercury per year used in antifouling paint in the
U.S. California-specific data not available.
Agriculture h
Seed and foliar application of mercury as pesticides and
fungicides. Between 1945 and 1970, 100,000 kg per year of
mercury was used in agricultural applications in U.S. Potential
contamination from both Central Valley and local agriculture.
Mercury mining
Production data presented to show relative activity in districts.
districts i
Loss to the environment unknown. Potential contamination
occurs primarily through the weathering and erosion of tailings
and other waste rock.
Mercury produced
Local watersheds upstream
Mining district name
(M kg)
of estuary
Clear Lake (1870-1957)
4.4
Cache Creek
Wilbur Springs (1862-1961?)
1.9
Cache Creek
Knoxville (1862-1961?)
5.7
Cache Creek
East Mayacmas (1870-1956)
13
James and Putah Creeks, Lake
Berryessa
Sulfur Springs (Vallejo)
0.59
Blue Rock Springs Creek, Rindler
(1852-1943)
Creek
Mt. Diablo (1863-1958)
0.38
Marsh Creek, San Joaquin River
(continued)
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