Varying levels found in study (February 7, 2016)

Several wells in Phelan, Pinon Hills above state chromium-6 levels

Five wells in the Phelan Pinon Hills Community Services District contain levels of hexavalent chromium that are higher than the state’s standard, according to data provided by the State Water Resources Control Board’s Division of Drinking Water.

A range of 10 to 16 parts per billion of chromium-6, a known carcinogen, were found in the five wells, the data showed; an additional well tested at levels that were near the state’s new standard of 10 ppb that went into effect Jan. 1, 2015 after the passage of Senate Bill 385.

A part per billion is the equivalent of one drop of water in an Olympic-size swimming pool, according to the Association of California Water Agencies.

Those five wells are in addition to all five wells servicing residents of Oak Hills that contain levels of chromium-6 between 18-23 parts per billion.

The Water and Sanitation Division of San Bernardino County’s Special Districts Department that manages water in Oak Hills submitted a draft compliance plan with the SWRCB last year that will allow the Water and Sanitation Division until Jan. 1, 2020, to lower chromium-6 levels into compliance with the state regulation.

Phelan Pinon Hills CSD General Manager Don Bartz told the Daily Press on Friday the difference between the situation in Oak Hills compared to Phelan and Pinon Hills is that the district has an alternative water source that will help remedy the chromium-6 problem there.

We’re doing a project that will cost about $17 million and will connect the water in the Meadowbrook Dairy with the wells we have now, Bartz said.

The water purchased from the Meadowbrook Dairy in El Mirage doesn’t contain chromium-6, according to Bartz, and approximately 10 miles of pipeline will be installed to connect that water with the CSD’s wells.

Once the water is blended in a to-beinstalled blending tank, the chromium-6 in wells servicing Phelan and Pinon Hills will be reduced to about 8 ppb, Bartz said.

We believe that project will go into effect in about 2019, he added.

[…]

Following the release of a similar letter to Oak Hills residents, the Daily Press requested chromium-6 data from the SWRCB for Victorville, Hesperia, Adelanto, Phelan Pinon Hills CSD, Oak Hills and Spring Valley Lake.

A review of that data showed one well in Hesperia contained 20 ppb, but that well was taken offline once the state standard changed from 50 ppb to 10 ppb, according to city spokeswoman Rachel Molina.

(Well) 26 is in standby mode, Molina told the Daily Press. It would allow the well to be used if some need arose; however, before that was done the city and the water district would have to get approval from the (SWRCB) and we’d be required to notify the public.

Because the well is offline, Hesperia is not required to lower the chromium-6 levels into compliance, according to Molina, who added that Well 21 was also taken offline for the same reason after the regulation changed.

[…]

Elsewhere, wells in Victorville, Adelanto, and Spring Valley Lake contain low levels of chromium-6, the data showed.

In Victorville, four individual wells contained levels of chromium-6 higher 10 ppb; however, those wells are part of a system of wells that contain water that’s blended and treated. Once the treated water reaches residences, the levels of chromium-6 are below 10 ppb, according to additional data provided by city spokeswoman Sue Jones.

The data provided for Adelanto — from 2013 — showed eight wells with non-detectable levels of chromium-6 — or .0000 — and the highest levels reported were fewer than 2 ppb in Well 05A.

Similarly, Spring Valley Lake’s highest levels of chromium-6 were under 3 ppb in Well 04.

The wells operated by Liberty Utilities, Apple Valley also contain low levels of chromium-6, according to Liberty’s General Manager Tony Penna.

Our wells consistently test in the range of less than 1 ppb to 6 ppb, Penna said via email. Due to the high quality of the water in our aquifer it does not require treatment. We do, however, add a general disinfection (low levels of chlorine). We monitor the water quality for all state and federal regulated constituents and will implement an effective treatment method if and when it is needed.

A variety of geochemical factors speak to why chromium-6 levels vary in the Victor Valley, according to the Mojave Water Agency’s Water Resources Supervisor Matt Howard.

The depth of the wells that service Phelan and Pinon Hills is one factor that plays into the variance, according to Bartz.

Our recharge comes off the mountains, Bartz explained, and that’s what brings the chromium into the water. It is coming from the aquifer, but not from the Mojave River. The chromium is just in one part of our basin. Our wells are approximately 1,000 feet deep, where there’s more chromium. Along the river they can be about 100 feet deep.

Source: Matthew Cabe, Daily Press


Local levels

Oak Hills, Well 01 — 23 ppb (all Oak Hills wells above 10 ppb)

Hesperia, Well 26 — 20 ppb (well is offline)

Phelan Pinon Hills CSD, Well 10 — 16 ppb (five wells above 10 ppb)

Victorville, Well 123 — 9 ppb

Apple Valley — less than 1-6 ppb (all wells)

Spring Valley Lake, Well 04 — 2.9 ppb

Adelanto, Well 05A — 1.7 ppb

*The listed wells contain the highest levels of chromium-6 in each municipality, county area and service district.