Page 184 - California Stormwater Workshop Handouts

ATTACHMENT G

REQUIREMENTS FOR DISCHARGERS WHO HAVE BEEN GRANTED AN
OCEAN PLAN EXCEPTION FOR DISCHARGES TO ASBS

a. A map of surface drainage of storm water runoff, showing areas of sheet
runoff and priority discharges, and a description of any structural Best
Management Practices (BMPs) already employed and/or BMPs to be
employed in the future. Priority discharges are those that pose the greatest
water quality threat and which are identified as requiring installation of
structural BMPs. The map shall also show the storm water conveyances in
relation to other features such as service areas, sewage conveyances and
treatment facilities, landslides, areas prone to erosion, and waste and
hazardous material storage areas, if applicable. The SWPPP shall also
include a procedure for updating the map and plan when changes are made
to the storm water conveyance facilities.

b. A description of the measures by which all unauthorized ASBS Non-Storm
Water Discharges (e.g., dry weather flows) has been eliminated, how these
measures will be maintained over time, and how these measures are
monitored and documented.

c. A description of how pollutant reductions in storm water runoff, that are
necessary to comply with these special conditions, will be achieved through
BMPs. Structural BMPs need not be installed if the Discharger can document
to the satisfaction of the Executive Director that such installation would pose a
threat to health or safety. BMPs to control storm water runoff discharges (at
the end-of-pipe) during a design storm shall be designed to achieve on
average the following target levels:

1) Table B Instantaneous Maximum Water Quality Objectives in Chapter II of
the Ocean Plan; or

2) A 90% reduction in pollutant loading during storm events, for the
applicant’s total discharges.

The baseline date for the reduction is March 20, 2012 (the effective date
of the ASBS Exception), except for those structural BMPs installed
between January 1, 2005 and the adoption of these special protections.
The reductions must be achieved and documented by March 20, 2018.

d. A description of how the ASBS Discharger will address erosion and the
prevention of anthropogenic sedimentation in the ASBS. The natural habitat
conditions in the ASBS shall not be altered as a result of anthropogenic
sedimentation.

e. A description of the non-structural BMPs currently employed and planned in
the future (including those for construction activities), and include an
implementation schedule. The ASBS Compliance Plan shall also describe
the structural BMPs, including any low impact development (LID) measures,
currently employed and planned for higher threat discharges and include an

Order 2014-0057-DWQ 3