CONTACTS 

SUBJECTS
PG&E submit induction study
941103 CDWR Induction Study meeting
Notes & Follow Up
Safety (Touch Voltage)
Design of TL route

0707 -    ..
0708 - Summary/Objective
0709 -
070901 - Followed up work at ref SDS 2 line 83.  Began review of Induction
070902 - Study and preparation of notes and follow up.
070903 -
070904 -     [Followed up at ref SDS 3 line 112.]
070905 -
070906 - Need copy of Maria's study report on a disk.
070907 -
070908 - There appears to be a conflict between PG&E's objective to only
070909 - disclose results of analysis so CDWR can determine mitigation they
070910 - feel is warranted, and the statement in the study on page 1 para 1.1,
070911 - that PG&E will:
070912 -
070913 -      •  Under steady state conditions... ...recommend mitigation if
070914 -         necessary for personnel safety.
070915 -
070916 -      •  Under fault conditions... recommend mitigation if necessary
070917 -         for personnel safety.
070918 -
070919 -
070920 - Since PG&E says it will do this, if it does not do so, then this
070921 - part of the record could be viewed later in an unfavorable light.
070922 -
070923 -
070924 - Three options emerge:
070925 -
070926 -    1.  Make no further submission so the draft document remains in
070927 -        the record with current mitigation comments.
070928 -
070929 -    2.  Submit a report that does not say "DRAFT", and which omits any
070930 -        discussion of mitigation, since that is outside the scope of
070931 -        the study.  Transmit study via a cover letter that states it
070932 -        applies the understandings from the review meeting.
070933 -
070934 -        Put in review meeting notes the discussion that mitigation is
070935 -        predicated on the particular project location, design, scope
070936 -        and use parameters relative to risk management evaluation.
070937 -        PG&E's draft study discussion on mitigation did not recognize
070938 -        the differences between PG&E's experience and the particulars
070939 -        of the Coastal Branch Aqueduct Phase II project, as brought
070940 -        out in the discussion with CDWR at the meeting.
070941 -
070942 -        We can say that PG&E will assist CDWR in further evaluations,
070943 -        or CDWR can contract separately to address specific project
070944 -        issues.
070945 -
070946 -    3.  Submit a "Final" study report that sets out the points con-
070947 -        sidered at the meeting.  State that PG&E makes no recommenda-
070948 -        tions on mitigation since this is a CDWR responsibility.
070949 -
070950 -
070951 -
070952 - I recommend option 2.
070953 -
070954 -
070955 -
070956 - Cholame 70kV Line Impact
070957 -
070958 - It is not clear from the study that the analysis includes current
070959 - from the existing Cholame line which appears to be closer to the
070960 - pipeline than does the new transmission line.
070961 -
070962 -     The drawing on page 3 (figure 2.1) seems to indicate that the
070963 -     existing line varies from 50 to 95 feet for about half the
070964 -     distance of the line, from Blue Stone to near Polonio Pass
070965 -     pumping plants.  It crosses the pipeline once near Blue Stone.
070966 -
070967 -
070968 - Actually, it appears the Chalome line is included as shown on page 5
070969 - under para 3.3 and further on page 7 under para 4.1 and figure 4.1.
070970 -
070971 - Figure 4.2 on page 8 seems to show considerably more induced current
070972 - from Blue Stone to near Polonio Pass pumping plants.  This is the
070973 - portion of the pipeline where the Cholame line and the new Transmis-
070974 - sion line both parallel the pipeline.
070975 -
070976 -
070977 -
070978 - Location of New Line
070979 -
070980 - The Study shows new transmission line appears to vary from a
070981 - "minimum" of 60 to 82 feet (see also figure 3.1 on page 5).  It
070982 - crosses the pipeline 5 times.
070983 -
070984 -     Note
070985 -     ----
070986 -     The 60' minimum distance in figure 3.1 seems to conflict with
070987 -     prior information from Bob Masuoka that the minimum distance of
070988 -     the new transmission line is 50 feet, ref SDS 1 line 460.
070989 -
070990 -        [Research on 941107 indicates 60' minimum is correct, per ref
070991 -        SDS 3 line 80.]
070992 -
070993 - Since there appears to be some flexibility in the precise location of
070994 - the new line, is there any advantage with respect to reducing the
070995 - potential harm of a fault by moving the line another 10 or 15 feet
070996 - from the pipeline?  If it would substantially reduce the level of
070997 - risk from a fault, to what extent is this possible without major
070998 - re-engineering and additional cost and/or delay?
070999 -
071000 -
071001 -
071002 - Risk of Fault
071003 -
071004 - There does not appear to be any quantification of the likelihood of a
071005 - fault which would seem to be a consideration of risk management, i.e.
071006 - the kinds and level of mitigation needed.
071007 -
071008 -     For example, if the risk is 10% chance of a fault per year, which
071009 -     means that a fault will occur once every 10 years, this is a
071010 -     greater risk than a 1% chance which is once every 100 years or
071011 -     .1%, once every 1,000 years.  Is the risk doubled for the portion
071012 -     of the pipeline where there are two transmission lines?  In that
071013 -     case a 10% chance goes to 20%, and this can make a considerable
071014 -     difference in the need for affirmative remedial measures.
071015 -
071016 -     Is there any history of faults for the Chalome line?  How long
071017 -     has it been installed?  Is the new line being constructed to the
071018 -     same standard?  Will maintenance on the new line be performed at
071019 -     the same level?
071020 -
071021 -     Can new maintenance procedures reduce the risk of past faults?
071022 -
071023 -
071024 -
071025 - Risk analysis by CDWR
071026 -
071027 - The rest of risk analysis must then be performed by CDWR based on the
071028 - particular design and use of its facilities.  How often and under
071029 - what circumstance will people come in contact with the portions of
071030 - the work susceptible to intolerable touch potentials?  What has been
071031 - the history of people being injured by touch potential on pipelines
071032 - adjacent to electrical transmission lines?
071033 -
071034 -
071035 -
071036 - Pipecoating Integrity
071037 -
071038 - Once CDWR is aware of potential induction valuations and the likeli-
071039 - hood of same under fault conditions, it would seem this matter is
071040 - entirely a design matter for CDWR, particularly in light of CDWR's
071041 - concern about cathodic protection.  PG&E can only provide information
071042 - from its own experience, which in this case appears to not apply to
071043 - the design of CDWR's project, as noted by Steve Burke in the meeting
071044 - with CDWR at ref SDS 2 line 114.
071045 -
071046 - PG&E can commission separate studies on this matter, however, it is
071047 - likely cheaper for CDWR to undertake such steps directly.
071048 -
071049 -
071050 -
071051 -
071052 -