State of California
                            AIR RESOURCES BOARD
                               Biltmore Hotel
                                Galeria Room
                              515 South Olive
                              Los Angeles, CA
                             September 30, 1977
                                 10:00 a.m.

77-21-1   Continuation of Public Hearing to Consider Amendment of
          South Coast Air Quality Management District Rules and 
          Regulations re Use of Natural Gas During Air Pollution  
          Emergency Episodes and Status Report on Compliance with 
          Rule 715.1.

77-21-2   Status Report on Chevron LSFO Investigation.

77-21-3   Report on Air Pollution Control Problems at Geothermal        1
          Power Plants.                                         

77-21-4   Other Business -
          a.   Research Proposals
          b.   Executive Session - Personnel & Litigation

                        ITEM NO.:  77-21-3

Report on Air Pollution Control Problems at Geothermal Power


1.   The Air Resources Board should consider becoming more
     involved in geothermal energy issues.

2.   If the Board wishes to become more involved the ARB staff
     should study further the adequacy of the local APCD programs
     and the coordination between counties to determine how an
     improved and unified approach can best be achieved.

3.   The Board should consider directing the staff to develop
     model air pollution regulations for geothermal developments
     for proposal to the districts or adoption by the Board.


Geothermal steam and hot water could potentially satisfy a
substantial amount of California's electrical power requirements
without the adverse environmental impacts associated with the
combustion of fossil fuels or the risks associated with the
storage of radioactive wastes.  The geothermal powerplants at The
Geysers in Northern California are presently generating about 500
Megawatts (MW) of electric power which is approximately four
percent of California's current electric power demand.  With the
exception of hydro-power, the electricity produced at The Geysers
is less expensive than electricity from all other sources.

Power production at The Geysers can potentially be expanded to
between 1,750 and 5,000 MW, however, the current level of power
production in Sonoma County has already generated complaints from
residents of Lake County located several miles downwind of the
rugged and unpopulated area where the power production activity
is now concentrated.  Odor from hydrogen sulfide gas which is
contained in the steam must be more stringently controlled if the
power production is to continue or expand.

Although the present control program of the Northern Sonoma
County APCD has reduced somewhat the H2S emissions, and will
reduce them further, full development of the resource requires
more stringent controls than are necessary to meet the District's
regulations.  A new approach to H2S abatement, different from the
approaches encouraged by the regulations of the local APCD's,
appears preferable.  Current regulations treat the steam producer
and the power plant operator (PG&E).  However, pre-cleaning of
the steam before it is delivered to the power plant appears to be
a superior approach.

At present, four new powerplants totaling about 400 MW are under
construction and application has been made to the PUC for
approval of two more with a combined capacity of 200 MW, one in
Sonoma and one in Lake County.  The violation of the air quality
standard in one county as a result of sources in the other raises
complex questions as to how the geothermal resources in both
counties can be developed without causing continued air quality
problems.  The Board may need to play a more active role in the
regulation of electricity generation from geothermal energy if
the full potential of the state's geothermal resources are to
ever be used to reduce dependence on sources of electric power
which are more damaging to the environment.