General Recommendations and Comments

• A separate study should be implemented to analyze the patterns found in all data sets collected by this program. Special emphasis should be placed on the extensive data sets collected in the marshes and coastal ocean through May 3-17, 2000. The analysis should attempt to identify the processes associated with contaminant transport through the marsh and coastal ocean systems. Once the dominant processes are identified, robust models of contaminant transport may be developed. A person experienced with a wide range of coastal processes would be ideal to coordinate the integrated investigations. Suitable candidates include university professors in coastal processes, environmental engineers, or people who have related programs in the area.

• Even though analyses of coastal ocean data may provide information on transport processes through coastal systems, they alone will not provide solutions to beach closures. The contaminant data from the watershed has to be analyzed in conjunction with these other data sets. This analysis will provide clues as to whether effective watershed management plans can be instituted to prevent future beach closures.It was not clear whether contaminants are stored in the sand on the beach, and then reintroduced into the surf zone on the next tidal cycle. Data from the intensive 24-hour water-sampling program may provide some insight. In particular, are contaminant levels highest when spring tides inundate the beach?

• Ten per-cent of all water-quality samples and/or isolates should be archived whenever possible. These samples would be useful for future fingerprinting of bacteria and/or chemicals studies that may help determine source identification.

• An assessment should be made of potential contaminant sources other than those mentioned in the studies. In particular, does the plume from the offshore discharge pipe ever come onshore? Is the SAR an important contaminant source?

• In many ocean systems, contaminants or pollutants that are spread by dispersal processes decrease monotonically from the source region, whether a marsh, a river, or an outfall plume. Hence, it was not clear how high concentrations of contaminants appeared at beach locations that are not adjacent to a specific source, such as the TM outlet. It is possible that surface films or flocculation processes allowed the bacteria to remain concentrated as they traveled, but the possible importance of this mechanism was not addressed in the conducted studies.

• The first, massive bacterial concentrations found in 1999 have a distinct ratio of bacterial types and no obvious source; therefore, it is possible that this was a unique contamination event. The subsequent contamination events tended to be at lower levels and have a different bacterial ratio. The Panel recognizes that the subsequent process studies in the marshes and coastal oceans are attempting to address more normal beach contaminant pathways.

• To determine whether bacterial concentrations are high enough to warrant beach closures, the waters off of Huntington Beach are sampled once a day in the early morning. Results from the hourly water-sampling program will be useful to determine if a daily, early morning sampling program is a viable method to assess bacterial contamination in the Huntington Beach surf zone. In particular, data are needed to determine the persistence of the contamination events. If the standards are exceeded only a few hours during the day, should contamination still be considered a serious problem?

• The 3-year historical contaminant data set suggests that there were about 100 events that would, under the present standards, close access to the ocean at Huntington Beach. Hence, contamination on the beach seems to be a persistent, not an unusual, occurrence. Some questions that the Panel thought could be addressed include:
  

1. Is there a historical record of illness associated with visits to Huntington Beach? If not, is a single high-level bacterial sample that is taken in the morning enough to warrant a beach closure?
2. Is a single water-quality sample representative of water quality at that site? A sampling program that took several samples at one time from each site would help determine the statistical variability of contaminant levels.
3. Can a suite of parameters be used as a contaminant alert rather than relying upon a model of the system.

OC Sanitation District - Huntington Beach Closure Investigation Phase I

USC Sea Grant - Huntington Beach Closure Technical Review

Coastal Runoff Impact Study 1

PFRD Medium Range Strategy

OC Sanitation District Investigation - Phase II
*note: Opens new window to OC Sanitation FTP site

Blue Ribbon Panel Report on Phase II

Coastal Runoff Impact Study 3 - Proposal