Central Coast ground water quality poorest in state

September 27, 2013


In southern San Luis Obispo County and northern Santa Barbara County researchers found more wells with high concentrations of nitrates, arsenic and molybdenum than anywhere else in the state, according to a recent report by the U.S. Geological Survey (USGS).

The USGS report lists water basins tested in 38 study areas. In the South Coast Range, which runs from Lompoc to Los Osos, researchers said 10 percent of the wells they tested had high concentrations of nitrate. Trace elements such as naturally occurring arsenic and molybdenum were found at high concentrations in 27 percent of aquifers in the South Coast Range.

In comparison, elsewhere in California researchers found high concentrations of nitrate in less than 1 to 8 percent of the groundwater used for public supply, and trace elements in 6 to 28 percent. High concentrations are defined as being above the U.S. Environmental Protection Agency or California Department of Public Health’s established maximum contaminant levels.

“Interesting, I’ve never seen molybdenum in 27 percent of the wells,” Justin Kulongoski, a USGS research hydrologist said.

One well in Arroyo Grande tested high in molybdenum. Most of the wells with high concentrations of molybdenum were located in the Santa Ynes and Lompoc areas. High levels of molybdenum can cause cancer and stunt growth in humans and animals.

In San Luis Obispo, one well located in the Tank Farm Road and U.S. Highway 101 area tested high for PCBs.

In Santa Maria, researchers found about 25 percent of the ground water basin had high nitrate levels. High levels of nitrate can stunt cognitive development in fetuses, infants and children.

Researchers found 8 percent of wells in the Paso Robles and Templeton areas, which are in the Monterey/Salinas study unit, had high concentrations of nitrate.

In Los Osos, researchers found one well high in nitrate. Because of reports of high nitrate levels in the Los Osos basin, a $173 million sewer is currently under construction.

Nevertheless, the USGS study focused on public supply aquifers which are generally several hundred feet deeper than residential wells. The study which led to the construction of the Los Osos sewer focused on the upper portion of the aquifer. Statewide, researchers have found about 40 percent of upper level aquifers have high nitrate levels.

As part of the statewide study assessing groundwater quality, scientists analyzed untreated groundwater from wells — not treated tap water. Groundwater is typically treated by water distributors prior to delivering it to customers to ensure compliance with water quality standards.

Elevated concentrations of nitrate generally occur as the result of human activities such as applying fertilizer, septic systems and livestock in concentrated numbers.


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Just wait until the tons of fertilizers being dumped on arid land and then washed through with millions of gallons of well water end up in the Paso GW Basin.

Los Osos is building a $200,000,000 sewer to address nitrates that aren’t there?

Can you say “Boondoggle!”

Los Osos water purveyors are putting in nitrate removal machines to make the one well potable. Cost = $600,000.

Can you say “Boondoggle!”

“Heavy Metals” is the elephant in the room that no staffer or politician wants to talk about… but if you walk around various public facilities check out all the water coolers and bottled water being consumed.

Seems like they might know something we don’t ?

Oh my God mixing water with water, the humanity.

So, years ago the water board forces Los Osos into a nightmare fight of self government for decades (the sewer wars), makes properties undevelopable if vacant land, unimprovable (not even a new bedroom) if occupied, and costs Los Osos condemned zone owners tens of thousands of dollars plus a costly and indeterminate future monthly fee,


this study finds a single Los Osos well with high nitrates? ONE ? So, did this recent study undersample Los Osos, or did the 1980’s RWQCB oversample, blunder, misanalyze, or spike samples to “go after” the little burgh of Los Osos? At first blush, something doesn’t seem to match up, and the losers are the residents/owners/renters of just another American town slammed under the hammer of local bureaucratic zealots.

Bingo lamecommenter,

The RWQB (an appointed board) has been setting it’s sights on all the unincorporated areas of the state and if Los Osos were not on it’s plate for them in this county, they would be focusing on the rest of the smaller villages or towns. Their goal is sewers for every town, because “we are polluting the states ground water”, regardless of cost or consequence.

The community of Los Osos exploded in growth under the counties guidance and thousands of homes were allowed to be built with inadequate services to handle the needs of water and effluent properly. In fact the RWQB pulled the permitting portions of the building permit process, because the county dropped the ball for decades by not having a mandated management plan in place. Septic systems were approved for decades without this management plan and today many small towns(Santa Margarita for example) are being forced to have engineered septic systems put in sometimes to tune of $45,000 to mitigate to the extreme.

Anyone seriously interested in finding out the facts of the RWQB, only need go to Central Coast Water Board at http://www.waterboards.ca.gov or speak to Harvey Packard(our local rep)…

Correction: The community of Los Osos exploded in growth in the ABSENCE of any county guidance. For decades it was considered the red headed orphan stepchild of the county.

Correction: All building in the county is by permit only and must meet the general plan for that specific area. A town of 15,000 was not built bootleg at night. County wide building growth has been capped at 3.2% for decades and the unincorporated areas that have grown fastest are those with the cheapest land and the easiest to get building permits.

And there still are “red headed step child” communities that get little to no attention until it is too late.

Talk to Bill Coy about the county’s lack of interest and involvement in Los Osos 1n the 70’s and early to mid 80’…that will open your eyes a bit.

Nitrates are manageable. It’s seawater intrusion that is irreparable. Too bad the LO sewer doesn’t address seawater intrusion, more costly projects on the way for this little burg. Thanks Gibson and Ogran, thanks for nothing.

Exceeds EPA limits eh? Just like naturally blowing dust. Now if we can only figure out how to blame dune buggies for molybdenum.

No link to the actual data? SKIP / NEXT.

Never, and I mean NEVER regurgitate scientific data WITHOUT links! This is teh intr0netz, we need links or else this is just more pablum for all we know. (and “USGS” ain’t gunna cut it).

Being the highly-talented search fu expert, I found what you are missing:

USGS website w/ info

the MEAT of the matter (warning, cutesy labels and charts found therein)

Now, as we all know (or can easily find out, as I just did =):

Molybdenum (Mo) is a metallic element that is naturally present, usually at low levels, in the earth’s crust. Trace amounts of molybdenum are necessary for human health, and are obtained from common foods in the diet such as leafy vegetables, legumes, grains and organ meats.

– and –

Naturally-occurring levels of molybdenum in groundwater are low; U.S. Geologic Survey found a median value of 1 μg/L nationwide. Most well owners do not need to include molybdenum during annual well testing.

So, what is our area’s level?

Exceptions in the Uplands study area include… eight detections of molybdenum greater than the USEPA lifetime health advisory level (HAL-US) of 40 µg/L.

(from here but to figure out what “Uplands study area” means, see the GRAPHIC on this page).

What a mess. Still not sure what they’re trying to get at.

The USGS’s horse blanket approach to researching and characterizing the quality of our water is vague at best.

When government is involved, it is often a solution looking for a problem. Of course, if there really is a problem, it is usually exacerbated by government solutions – but at least a small handful of very vocal people can “feel better.”

Got a clue, do you think there is any connection between major historic agriculture and these contaminants?

And I have to agree with Jorge, never let a good crisis go to waste.

It fuels the engines of government and the multitude of agencies salivating over the possibility of a impending study or report that always leads to a mandated ruling which in turn always leads to a potential funding source for said agencies….

Contrary to the apparent beliefs of a lot of posters on here, everything single thing that happens is not a conspiracy. That’s all I’m saying.

Quite true. Even though it’s really all Obama’s fault, eh?

I agree that agriculture (grazing and farming) has no doubt contributed to the increased nitrate levels, however Mo (molybdenum) is a much more complex issue, often times very difficult to pinpoint a source.

Past studies have suggested that the mobility of Mo is directly related to diminished amounts of iron, sulfate, and oxidizing bacteria in the soil. In depth geochemical studies of central coast aquifers may help in pinpointing a source(s).

Good point pelican, it is a very complex issue.

Why do some wells at great depth, Santa Margaritas well number 3 for example, have high levels of minerals, arsenic and other “contaminates”? The town is surrounded by range land with little farming and only 553 homes with septic systems. The well was drilled to a depth of 750 feet in the late 90’s into a deep fractured rock aquifer and well past the communities septic system influence and upstream of town.

And I agree with Jorge, it appears to me to be a pitch for another cash cow for the state and county. Even if there is nothing done, many studies will be and be billed to us all at increased services rates.

Never let a good crisis go to waste…

Sounds like a sales pitch to get off of local water, sell us imported water and build more sewer systems, two the the three cash cows that gov covets, the third being trash. Also, we are now being charged for the air we breath as well as funding the fines that regulatory agency impose on each other.

Get a clue. Has it never occurred to you that it might actually be important for us to know how safe the water supply is?

If it is safe enough for the grape vines, I can drink the wine – har har, I get your point and yes, have a good weekend.

Sounds like you would rather be poisoned than (possibly) fooled by your government. You’re too sharp to fall for the old “reality” trick.

Actually, it may be just fine for grape vines, and still poison you — and the wine they make from the vines, too.

Can you link us to your research?