Q: What is Perchlorate?

Perchlorate is a chemical that comes in four main forms: potassium perchlorate, ammonium perchlorate, magnesium perchlorate and sodium perchlorate. Perchlorate can be either naturally occurring or manmade. Most of the perchlorate manufactured in the United States is used as a primary ingredient of solid rocket propellant. Perchlorate is also used in the manufacture of flares, fireworks, munitions, and in a wide variety of other industrial processes. According to the United States Food and Drug Administration (FDA), naturally occurring perchlorate is found in nitrate fertilizer deposits in Chile.  Perchlorate is highly soluble and travels in underground water almost as fast as the water itself.

Q: Why is Perchlorate in our water?

Perchlorate has been detected in all of the City of Rialto's groundwater wells which pump from the Rialto-Colton Groundwater Basin, Rialto's primary source of drinking water. Water samples taken from monitoring wells which potentially responsible parties have been ordered to install and operate by the Regional Water Quality Control Board show perchlorate at levels as high as 10,000 parts per billion (ppb).  At Rialto's request, the Regional Water Quality Control Board has ordered some suspected polluters to take soil and water samples at various locations and depths, so that characteristics of the plume of perchlorate contamination can be determined.  This map shows the 160 acre site, and the County of San Bernardino's landfill.

The introduction of perchlorate into the Rialto-Colton Groundwater Basin dates back to World War II. After the bombing of Pearl Harbor, the United States War Assets Administration (now the Department of Defense) purchased 2,800 acres of property in northern Rialto, where it developed munitions bunker storage facilities to temporarily store munitions to minimize the quantities of munitions vulnerable to attack in the highly populated Los Angeles Port region. The bunker facilities were known as the Rialto Ammunition Backup Storage Point (otherwise known as the "RASP" Site). The RASP site included a vast network of train rail spurs used to transport munitions to and from the bunkers, and rail lines from Rialto to the Port of Los Angeles.  Based upon its investigation, Rialto has concluded that the United States transported over 20 million pounds of perchlorate-containing rockets, munitions and other articles through Rialto during the operation of the RASP Site between 1942 and 1946.

After the war, the United States sold the RASP Site property.  Since that time, the former RASP site has been, and continues to be used by a variety of different defense contractors, fire works manufacturers and others who use perchlorate in their manufacturing processes, or who use them in their products.

Rialto believes that the source of the perchlorate is from releases, disposal, and discharges of perchlorate by these polluters over the last 65 years.  The discharged perchlorate has now taken the form of an underground plume beneath the City, dissolved in the groundwater, moving southeasterly at a rate of up to 3 feet per day. It is unknown just how deep the plume extends at its deepest point, but the aquifer is assumed to be approximately 1000 feet deep in places.  The plume is believed to be over six (6) miles long, and could be several miles wide.  The plume of contamination is believed to originate from two source points within the RASP Site property. The first source point is referred to as the "160 acre parcel" and the other source point is the County of San Bernardino Mid Valley Sanitary Landfill. Click here to view the map of the 160-acre site, and the County of San Bernardino’s landfill.

To learn more about the two major source areas, click below:

• The 160 Acre Site
• Mid Valley Landfill

Q: Is it safe to drink perchlorate?

The Food and Drug Administration (FDA) states that, at certain doses, perchlorate can interfere with iodine uptake into the thyroid gland, disrupting its functions, and has been investigating levels of perchlorate found in food supplies.  You can find information about this at http://www.cfsan.fda.gov/~dms/clo4qa.html

Perchlorate has been used as a drug to treat hyperthyroidism and to diagnose disorders related to thyroid or iodine metabolism.  While the FDA's Center for Drug Evaluation and Research web page shows that one drug named Perchloracap, which contains potassium perchlorate, was approved in November 1974, its marketing has been discontinued and its supplies were anticipated to be depleted by the end of 2005.  You can find this information at:  http://www.accessdata.fda.gov/scripts/cder/drugsatfda/index.cfm?fuseaction=Search.DrugDetails and under the FDA site under "Drug Shortages" at http://www.fda.gov/cder/drug/shortages/#disc

In the introduction of the 2005 National Academy of Sciences report  entitled "Health Implications of Perchlorate Ingestion" it is reported that over the past 50 years, perchlorate has been used to diagnose and treat thyroid disease.  It was used in the 1950s and 1960s to treat hyperthyroidism associated with Graves disease (EPA 2002a).  The extent of its use was curtailed when severe hematologic side effects were reported and better antithyroid drugs became available.  Today, perchlorate is used diagnostically to detect defects in the synthesis of thyroid hormones.  It is also used as treatment for patients who have developed hyperthyroidism after exposure to the antiarrythmic drug amiodarone (Martino et al. 2001).  However, the FDA does not recognize perchlorate as a pharamaceutical to treat endocrine or metabolic disorders, and it is rarely used today to treat any type of hyperthyroidism in the United States. You may view the full report at http://www.nap.edu/catalog/11202.html#toc.

In adults, the thyroid helps to regulate metabolism.  In children, the thyroid plays a major role in proper development in addition to regulating metabolism.  Impairment of thyroid function in expectant mothers may affect the fetus and newborn and result in effects including delayed development and decreased learning capability.  Impairment of thyroid function in nursing mothers may have similar effects on their newborn.

A December 11, 2006 the National Institute of Environmental Health Sciences report titled “The Evaluation of the U.S. EPA’s Preliminary Remediation Goal for Perchlorate in Groundwater:  Focus on Exposure to Nursing Infants, " concludes that the unborn child may be particularly vulnerable to perchlorate toxicity and that the U.S. EPA Preliminary Remediation Goal of 24.5 ppb should be evaluated in light of these exposures. You can find the report here.  

On October 5, 2006, the Los Angeles Times and the Sacramento Bee reported that many women exposed to perchlorate have suppressed thyroid function, which can lead to health problems for themselves and their offspring, citing a recent study by the Centers for Disease Control and Prevention published October 3, 2006. The study is the first research that links reduced thyroid hormones in people with low amounts of perchlorate routinely found in the bodies of Americans nationwide. Women with low iodine levels- more than one third of U.S. women- were most at risk from ingesting the chemical, according to the report. 

The Los Angeles Times article can be found here.  The Sacramento Bee article can be found here. The full National Institute of Environmental Health Sciences report can be found here.

 Different regulatory and governmental agencies have adopted different standards and have differing opinions on whether and how much perchlorate is safe for humans to ingest. For instance:

• The State of Massachusetts has set a maximum allowable level in its water at 2 parts per billion (ppb). You may learn more about Massachusetts perchlorate response by visiting its website at:   http://mass.gov/dep/water/drinking/percinfo.htm
  
• California has set a Public Health Goal of 6 ppb and has proposed a Maximum Contaminant Level for perchlorate in drinking water of 6 ppb. California previously allowed up to 18 ppb. To learn more about California Activities regarding perchlorate please visit its website at http://www.dhs.ca.gov/ps/ddwem/chemicals/perchl/default.htm

• The Department of Defense has stated its belief that up to 200 ppb is safe.

• The United States Environmental Protection Agency has adopted a reference dose for perchlorate of 0.0007 milligram/kilogram-day, which leads to a Drinking Water Equivalent Level of 24.5 ppb.  The reference dose and its corresponding Drinking Water Equivalent Level are respectively the recommended "to be considered" value and the preliminary remediation goal for perchlorate. To read the EPA 1/26/2006 Memorandum regarding Assessment Guidance for Perchlorate, click here.   

Because of these differences in opinion, the City of Rialto has adopted a "Zero Tolerance Policy" towards perchlorate. To learn more about the City's "Zero Tolerance Policy," click here.

Q: Can perchlorate be removed from the water?

Yes, but it is expensive to remove perchlorate from water. Currently, there are two primary treatment technologies in use in the United States:  ion exchange and biological remediation technologies.  Research is currently underway to develop other new, cheaper technologies. 

The ion (anion) exchange technologies include: (1) Water softening, which removes ions from the water and replaces them with sodium (Na+) and chloride (Cl-) ions, and (2) Deionization, in which ions are removed and replaced with hydrogen (H+) and hydroxyl (OH-) ions, which can combine to form water. 

The installation of ion exchange treatment equipment costs approximately $1 million  per water well, and it costs up to $500,000 per year to operate the perchlorate removal equipment at each well.  Research is currently underway to develop other newer, cheaper technologies.

Rialto has caused wellhead treatment facilities to be installed on three of its wells in and around the Rialto-Colton Groundwater Basin. It has increased its pumping in those wells, and left the other polluted wells out of service. Rialto is treating the water drawn from those wells until it tests "non-detect" for perchlorate, using state-approved testing methods.

Biological remediation technologies are still being developed and their use for removing perchlorate from drinking water is heavily regulated.

Q: How long will perchlorate remain in the groundwater?

No one can say for sure at this time how long the perchlorate will remain in the Rialto-Colton Groundwater Basin. It has already been there for over 65 years, and it is getting worse, not better. The plume of contamination continues to move southeasterly, towards the City of Colton and the levels of perchlorate detected in local wells continue to increase. The plume will likely remain indefinitely until removed through implementation of a clean-up and abatement plan. Rialto is assisting the Regional Water Quality Control Board to force the responsible parties to pay in full for, and to perform, the characterization of the plume of contamination, the development and implementation of a clean-up plan and the provision of replacement water to the affected water purveyors.  The Regional Board's orders should remain in effect until the water basin is completely remediated to its original state, before the release of perchlorate. To see the water orders which the City has successfully assisted the Regional Water Quality Control Board in issuing, go to: http://www.waterboards.ca.gov/santaana/html/perchlorate13267.html

Even with aggressive treatment starting soon, some estimate that it could take as long as 30 to 50 years of treatment before the perchlorate is remediated to non-detect levels. The time estimate will become more predictable as the plume is more fully characterized and its width, depth and length are determined.

Q: Where is the plume of contamination now?

Q: Can the source area and the plume be cleaned-up?

Yes, the technology to "pump-and-treat" the plume exists today. However, in order for the cleanup to be effective, the plume must first be adequately characterized, and then additional wells, treatment facilities, possibly reinjection wells and similar other facilities and techniques will be required before the plume can be fully remediated. Ideally, the perchlorate-contaminated water plume can be pumped out of the ground, the water treated and then either used or reinjected back into the ground. In some cases removal of contaminated soil may be required. These questions will begin to be answered more fully as the plume is characterized more definitively.

Q: Who is going to pay to clean up the source area causing the plume?

Rialto's policy is to take the actions necessary to force the polluters and their insurance companies to pay the tab in full for the clean-up.  The ratepayers of the City should not have to pay to clean up pollution left by others.

The City has implemented a three part clean-up plan to accomplish this goal, as follows:

1. Pursue all of the polluters in litigation so that they and their insurance companies are ultimately obligated to pay for the clean-up in full.
2. Pursue Orders from the Regional Water Quality Control Board against the polluters requiring them to clean-up the basin sooner, rather than later.
3. Seek out State and Federal funds to pay for treatment in the meantime.

   Other water purveyors, such as the West Valley Water District and the Fontana Water Company have raised rates paid by Rialto citizens to pay for the treatment costs incurred by them. Over time, if no one forces the polluting corporations and their insurance companies to pay, then the ratepayers and citizens of Rialto and surrounding communities will have to pay by virtue of our continuing need to drink the water. If we want to drink the water, then we will have to clean it, and to clean it we will have to pay for treatment. It is the City's goal to avoid a situation where the ratepayers are left to pay this massive tab. For more on the City's plan to force the polluters to pay, click here.