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 Health for violating storage requirements for creosote-treated wood. The rationale for the
citations was apparently that creosote components of the piling "improperly" stored on the
ground prior to installation would leach into the ground and harbor during rainfall events. The
creosote-treated piling installed in the harbor was not cited by the regulators. Because of these
citations, PWC San Diego understandably no longer wishes to store and use treated wood piling
and are looking for alternatives such as plastic piling.
There are a number of other instances where state, county, city, or other agencies have
successfully restricted the use of treated wood in the marine environment. For example, local or
state agencies may require time consuming and costly environmental assessments for projects
involving the use of treated wood in aquatic environment whereas alternative materials usage will
not. The concern is that the treated wood will produce a "discharge" that will not meet local
water quality standards or cause sediment contamination in violation of sediment standards. In
addition, states such as California and Washington are proposing to regulate the disposal of
treated wood under state hazardous-waste regulations.
IMPROVED PRACTICES AND METHODS
In any case, whether or not regulatory agencies are scrutinizing local treated wood usage
practices or whether or not there is high potential environmental risk, the use of best management
practices (BMP) is required. BMP will minimize environmental risk and ensure the greatest
return on investment dollars by addressing quality assurance issues.
A full discussion of recommended BMP for specifying and using marine treated wood
follows below. Appendix B provides a summary of BMP and how they should be implemented.
An adjunct to Appendix B is Appendix C which outlines potential problems that activities may
face when using treated wood and possible means of resolving the problems.
1. Proper Performance. The greatest improvement in Navy practice related to the use
of treated wood in the marine environment would be the full implementation of Navy quality
assurance policy and marine construction standards as outlined in Navy criteria documents and
MO-312. AWPA commodity standards which proscribe acceptable preservatives, treatment
methods, treatment results in terms of retention and penetration, and appropriate use of the
treated material must be used. Full compliance by all contractors and federal agencies involved
must be insisted upon. Premature failure of treated wood can almost invariably be attributed to
either (1) the use of wood that does not meet strict treatment standards, or (2) improper
construction and installation practices that expose untreated wood. The primary treatment
standards are penetration and retention of the preservative. If the penetration is too shallow or
the level of retention is too low, then poor performance will result.
Consideration should be, given to the use of plastic-covered wood piling in lieu of treated
wood. Experimental polyurethane coating and polyethylene wraps on treated and untreated
fender piling in Los Angeles Harbor continues to provide excellent service after 11 years of use.
The plastic prewrapped or coated piling have the advantages of wood, i.e., flexibility and strength,
are environmentally acceptable, and, as long at the coating or wrap remains intact, impervious to
marine borer damage. If these experimental piling are to be used as fenders, then polyethylene rub
strips or other means should be used to prevent abrasion damage to
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