Pin It
Favorite

Nitrates under the rug 

A study from Los Osos' past calls its future into question

Wastewater expert Roy Spalding is quite accustomed to dealing with shit.

For 40 years, he has studied it, taught it, and consulted on it to municipalities and regulatory agencies across the nation. His knowledge of the wastewater spans its many forms-residential effluent, agricultural runoff, industrial waste, and, thanks to the Los Osos debate, political sewage.

Now he can tell his students that he's even seen shit hit the fan.

When Spalding moseyed into his campus office at the University of Nebraska-Lincoln on July 10, the researcher found heaps of e-mails and phone messages, all of which dealt with a topic he had forgotten long ago. Apparently, folks in a coastal California bedroom community wanted to see wastewater analysis he conducted with samples from a certain groundwater table.

Almost two decades ago.

The enthusiastic salvo sent Spalding on mad search, attempting to dig up any sign of the age-old records.

"It was interesting to see what I was doing in 1987," he mused.

Sixteen-hundred and sixty-eight miles away and 60-some hours earlier, a Fresno engineering consultant named Ken Schmidt dropped Spalding's name before a fervent crowd assembled at the South Bay Community Center in the still-sewerless berg of Los Osos. The comment reignited a long-extinguished debate-in the mainstream discourse, at least-over the source of the nitrates contaminating the Los Osos basin. Historic arguments for a sewer strongly hinged on a predominantly septic source.

Spalding, widely considered one of the world's leading researchers in wastewater analysis, scrutinized samples collected in February and June of 1987. Spalding attributed the nitrates to "multiple sources," Schmidt announced at the recent meeting. The comment caused quite a stir, and launched a quest to sniff out the report that time forgot.

Eventually, Spalding drudged up a correspondence with various county officials that included the actual readings from 1987. Simultaneous Freedom of Information Act (FOIA) requests from New Times to the Community Services District (CSD), county public works, and the Regional Water Quality Control Board yielded more shrugs than answers-with one exception.

A package faxed over by the water board contained a letter to public works official Percy Garcia, dated August 31, 1987. In this dispatch, Spalding dropped the bomb:

"While there could be, and probably is, a contribution from septic system laterals, the contribution is probably small in relation to the total nitrate," he wrote.

In other words, the regulatory hounds might be chasing the wrong fox. Something other than septic tanks might prove the dominant source of contamination.

A subsequent memo by Dennis Rolston of UC Davis called that conclusion into question. The emergence of such blockbuster data, however, lends at least some credit to preexisting claims that regulators suppressed some inconvenient research.

Document timestamps indicate that Sorrel Marks of the water board received the Rolston memo on Feb. 16, 1995. The key question for that regulatory body remains: When, exactly, did water board officials become aware of the Spalding report, which the county-not they-commissioned?

"Off the top of my head I can't remember when we received it," Marks said.


County public works stamped that packet of documents as received.

Spalding, while he said couldn't recall specifics, turned up another letter, dated Feb. 15, 1988, referencing a water board "staff report" on his isotope readings.


The science

Volatilization is a two-stage controlled evaporation of a compound to differentiate chemical isotopes by their source. Confused? Look to the word root. The etymology reaches back to the Latin volatus-"to fly." By heating up a compound, scientists can examine with precision equipment how certain elements vaporize. The question in determining the chemicals' source is: How willing was the nitrogen in the groundwater nitrates to fly out of its chemical bonds?


According to Spalding, not willing enough.

With the readings, the researcher drafted a table comparing the nitrate concentration in the groundwater samples to a ratio indicative of the nitrogen flight. Of the 17 total readings, all but two landed between +6 and +10 percent-a murky region for determining the source. Nitrogen from leached septic nitrate, Spalding said, should clock in at well above +10 percent.

He based this conclusion on history of data testifying to that fact. UC Davis' Rolston-who wasn't available for comment-stated in his memo that he found readings similar in range to the Los Osos basin at two sites near Davis and in the Salinas Valley. In both instances, he claimed, the source proved leaching septic lines.

"I don't know how Rolston could come to the conclusion the Los Osos nitrates were [definitively] from septic tanks," Spalding responded.


The policy

The discovery of Spalding's research potentially impacts the Los Osos situation in several ways. For one, it joins a 1994 nitrogen study as a scientific foundation for claims that the nitrates might hail from a multitude of sources and, therefore, a sewer will achieve relatively little in remedying the sullied upper aquifer.

Agriculture, horticulture, and California motor-culture constitute three of a bounty of usual suspects. Because Spalding asserted that human and animal wastes land higher in the spectrum and pesticide-based contamination much lower, the particularly moderate readings suggest Los Osos may harbor a potpourri of nitrate pollution.

"I want to know why this study was suppressed," CSD board president Lisa Schicker said. "I also want to know if there were other studies like it."

The most pressing issue, however, remains the current regulatory entanglement caused by the water board's recently drafted cease-and-desist orders (CDOs).

Marks declined to comment on how Spalding's research might affect the CDOs levied against the Los Osos 45-a bushel of prohibition-zone residents identified as polluters by the water board. Those mandates were issued specifically because of nitrate contamination.

As far as sewer plans go, the data in the study is old even Spalding couldn't believe the Ososites would find it relevant. Yet, while it's perhaps too old to affect current negotiations, CSD board members said the data should provide a spark to reexamine the issue.

"We should have another isotopic study now," Schicker commented. "It would be very useful to have that data." ?

Staff Writer Patrick M. Klemz can be reached at pklemz@newtimesslo.com.

Pin It
Favorite

Comments

Subscribe to this thread:

Add a comment

Search, Find, Enjoy

Submit an event

© 2017 New Times San Luis Obispo
Powered by Foundation