PERCHLORATE Background and History Occurrence Toxicity 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 ?) If so, should we worry about this ? (Define the TOXICITY) With this information, we can start to Make REGULATORY DECISIONS

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 1908 - First Manufactured at Niagara Falls, Eventually at 9 Locations, now only in Cedar City, UT 1950s – Used as Human Drug 1980s - Aware of Perchlorate Use at CA and NV Superfund Sites 1990s - Aerojet in Rancho Cordova Discovered at > 1000 ppb in Groundwater

Perchlorate HISTORY 1992 and 1995 - EPA Provisional Reference Dose at 4 - 18 ppb 1997 - Analytical Breakthrough to 4 ppb 1998 - Region 9 Requests Manufacturer’s Information 1997 and 1998 - Region 9 Alerts EPA HQ, Regions, and States

Perchlorate USES 90% Manufactured for Solid Rocket Fuel Explosives Fireworks, Flares and Smoke Markers Reported in Nitrate Fertilizer from Chile

Perchlorate SHIPMENTS Manufacturer's Information from Region 9 Requests About 240 Facilities 40+ States Information Not Available Before 1970s

PERCHLORATE MANUFACTURERS and USERS APRIL, 2003

Perchlorate OCCURRENCE CALIFORNIA 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 CALIFORNIA Over 6700 Water Supply Wells Tested Detected in 350 sources, 5+ %

US EPA September 2004 : www.epa.gov/fedfac/documents/perchlorate.htm  

2002 and 2004 Average Perchlorate Concentrations Lower Colorado River 2002 and 2004 Average Perchlorate Concentrations 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

U.S. EPA Region 9 PERCHLORATE RELEASES State Lead Sites Lincoln N E V A D A Reno Lake Superfund Sites Tahoe Carson City Site Assessment Areas Sacramento Aerojet Sonoma Rancho Cordova Colorado River Contamination LLNL Site 300 San Francisco UTC San Jose Santa Clara San Martin Hollister (2) Tulare County Las Vegas PEPCON C A L I F O R N I A BMI Kerr-McGee A R I Z O N A Casmalia Vandenberg AFB Santa Clarita Edwards AFB San Fernando (2) Santa Susanna Rialto NASA JPL Redlands San Gabriel ( 3) San Nicholas Chino Basin(2) White Tanks Phoenix Island Wyle Stringfellow Los Angeles Corona Goodyear Gila River Brownfields El Toro MCAS U.S. EPA Region 9 Tucson Benson Apache June 2004 CA-32 AZ-7 NV-3 Davis Monthan M E X I C O