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PERCHLORATE Kevin Mayer
U.S. EPA, Region 9
Background and History
Occurrence
Toxicity
Regulatory Status
Perchlorate PROBLEM STATEMENTS
Is this Chemical in the Environment ? (Is there an EXPOSURE ?)
With this information, we can start to Make REGULATORY DECISIONS
If so, should we worry about this ?(Define the TOXICITY)
Perchlorate CHEMISTRY
Dissolves and Moves Like Salt in Water
Highly Soluble, Mobile, Stable
Hard to Treat by Usual Methods
Hard to Detect Below 400 ppb, until March 1997
4
Perchlorate HISTORY
1980s - Aware of Perchlorate Use at CA and NV Superfund Sites
1990s - Aerojet in Rancho Cordova Discovered at > 1000 ppb in Groundwater
1908 - First Manufactured at Niagara Falls, Eventually at 9 Locations, now only in Cedar City, UT1950s – Used as Human Drug
Perchlorate HISTORY
1992 and 1995 - EPA Provisional Reference Dose at 4 - 18 ppb
1998 - Region 9 Requests Manufacturer’s Information
1997 and 1998 - Region 9 Alerts EPA HQ, Regions, and States
1997 - Analytical Breakthrough to 4 ppb
Perchlorate USES
90% Manufactured for Solid Rocket Fuel
Explosives
Fireworks, Flares and Smoke Markers
Reported in Nitrate Fertilizer from Chile
Perchlorate SHIPMENTS
Manufacturer's Informationfrom Region 9 Requests
About 240 Facilities
40+ States
Information Not Available Before 1970s
PerchlorateOCCURRENCE
Detections Reported in 35 States
AL, AZ, AR, CO, FL, GA, IA, IL, IN, KS, LA, MD, MA, MI, MN, MS, MO, NE, NV, NJ, NM, NY, NC, OH, OK, OR, PA, SC, SD, TX, UT, VA, WA, WV and PR
CALIFORNIAOver 6700 Water Supply Wells TestedDetected in 350 sources, 5+ %
In 1997, 900 pounds per day entered Lake Mead
By 2001, about 500 pounds per day
Measurable entire 300 miles to Mexico
Used by Las Vegas Los Angeles, San Diego, Phoenix and agriculture
Water supply for over 15 million people
500 ppb 150 ppb
10 ppb 7 ppb
6 ppb 4 ppb
5 ppb <4 ppb
5 ppb <4 ppb
Lower Colorado River 2002 and 2004 Average Perchlorate Concentrations
PERCHLORATE RELEASES
Superfund Sites
Site Assessment Areas
Colorado River Contamination
San Fernando (2)
Santa Clarita
SanFrancisco
Sacramento
San Jose
Los Angeles
Lake Tahoe
M E X I C O
C A L I F O R N I A
Carson City
Reno
Las Vegas
N E V A D A
A R I Z O N A
Hollister (2)
Edwards AFB
Rialto
Corona
Santa Susanna
El Toro MCAS
Lincoln
LLNL Site 300
Phoenix
Tucson
San Nicholas
Stringfellow
Benson Apache
Gila River Brownfields
Davis Monthan
Goodyear
White Tanks
Rancho Cordova
Aerojet
BMI Kerr-McGeePEPCON
Island
State Lead Sites
Tulare County
Vandenberg AFB
Casmalia
San Gabriel ( 3)
NASA JPL
U.S. EPA Region 9
Redlands
Wyle
Chino Basin(2)
UTC
San MartinSanta Clara
Sonoma
June 2004 CA-32 AZ-7 NV-3