Oasis Mobile Home Park Public Water System; Thermal, CA

• Background
• Sampling Results
• Sampling Zone Map
• Documents
• Footnotes

Background

On September 14, 2021, EPA issued an Emergency Administrative Order under Section 1431 of the Safe Drinking Water ActSafe Drinking Water Act An Act passed by the US Congress in 1974. The Act establishes a cooperative program among local, state and federal agencies to insure safe drinking water for consumers. (SDWA) 42 U.S.C. § 300i to Oasis Mobile Home Park, Thermal, California. EPA determined that conditions exist at Oasis’ public water system that may present an imminent and substantial endangerment to the persons served by the public water system. EPA’s decision was based on sampling results that indicated high arsenic levels, that exceeded the maximum contaminant level (MCL) ^[1], in the distribution system (premise plumbing), well source water, and at the entry point to the distribution system.

The Order and its requirements are necessary to ensure adequate protection of public health at the public water system. The Order requires, in part, that Oasis provide alternative water, notify the public of the high levels of arsenic, identify and correct the cause of the high arsenic levels, and perform increased monitoring and reporting.

Sampling Results

As part of EPA’s ongoing enforcement, EPA took arsenic ^[1] and iron ^[2] samples (iron levels were taken to better understand arsenic levels) at the kitchen taps of homes located in Oasis. The results, recorded in parts per billion (ppb) are below.

To protect resident privacy, we are committed to safeguarding sensitive information by not disclosing specific unit numbers in the sampling results. Instead, we are using unique identifiers (such as Zone 3/A1) that allow us to publicly report changes in arsenic and iron levels for each unit without compromising individual privacy. For example, location Zone 3/A1 represents the same unit in all sampling results.

See the Sampling Zone Map for locations of the zones at the site.

* Sample was compromised during the shipping and handling process. No data is available.
^ Sample was collected from the bathroom tap instead of the kitchen tap.
N/A: Resident unavailable for sample collection.

Sampling Zone Map

To protect resident privacy, we are committed to safeguarding sensitive information by not disclosing specific unit numbers in the sampling results. Instead, we are using unique identifiers (such as Zone 3/A1) that allow us to publicly report changes in arsenic and iron levels for each unit without compromising individual privacy. For example, location Zone 3/A1 represents the same unit in all sampling results.

Documents

• U.S. Department of Justice Complaint Against Oasis Mobile Home Park for Alleged Safe Drinking Water Act Violations (pdf) (245.18 KB, August 15, 2023)
  United States Department of Justice (DOJ) Civil Complaint, filed on behalf of EPA, against the operators of Oasis Mobile Home Park, located in the Eastern Coachella Valley in Southern California, alleging failure to properly maintain and operate Oasis’ primary drinking water well, treatment and distribution systems and wastewater system, and failure to perform corrective measures to protect the health of those who consume the drinking water.
• Emergency Administrative Order: Oasis Mobile Home Park (pdf) (225.95 KB, September 14, 2021)
  Emergency administrative order in the matter of Oasis Mobile Home Park; the Estate of Scott Lawson Sr.; Cheweka Salazar Lawson; Sophia Lawson; Scott Lawson Jr.; Martin Lawson; Kim Lawson Jr.; Rose Saubel; and Julie Lawson, Public Water System, PWS ID. No. 090605129 Respondents.
• Oasis Mobile Home Park Drinking Water Fact Sheet (pdf) (1.79 MB, March 2023)
  Factsheet with March 2023 drinking water information for Oasis Mobile Home Park.
• Oasis Mobile Home Park Water Filtration System Fact Sheet (pdf) (912.96 KB, February 2023)
  Information about water filtration systems for tap water, water sampling, how to reduce the level of arsenic build-up in plumbing, and notification of sampling results.
• Residential Flushing Procedure Handout (pdf) (627.64 KB, May 2023)
  EPA flyer with information about residential flushing procedures at Oasis Mobile Home Park, Thermal, CA
• Arsenic and your Distribution System Brochure (pdf) (573.52 KB, EPA 816-F-07-005)

Footnotes

1. EPA has established National Primary Drinking Water Regulations (NPDWRs) under the Safe Drinking Water Act (SDWA) that set mandatory water quality standards for drinking water contaminants. These are enforceable standards called "maximum contaminant levels" (MCLs) which are established to protect the public against consumption of drinking water contaminants that present a risk to human health. An MCL is the maximum allowable amount of a contaminant in drinking water which is delivered to the consumer. EPA set the MCL for arsenic at 10 parts per billion (ppb) to protect consumers against the effects of long-term, chronic exposure to arsenic in drinking water.
2. EPA has established National Secondary Drinking Water Regulations (NSDWRs) that set non-mandatory water quality standards for 15 contaminants. EPA does not enforce these "secondary maximum contaminant levels" (SMCLs). They are established as guidelines to assist public water systems in managing their drinking water for aesthetic considerations, such as taste, color, and odor. These contaminants are not considered to present a risk to human health at the SMCL. The SMCL for iron is 300 ppb.