HOLMES & NARVER, Inc
ENGINEERS-CONSTRUCTORS
Wve
oy
TO:
S. P. Howell
_j08:
G2
FROM:
L. S- Hammond
__RE:
Precise Surveys
Bikini Atoll
DATE:__July31,1957=
Reference is made to J6=3816 w/encl. Secret,
dated June 25, 1957,
which specifies a first order horizontal and vertical interrelation between scientific stations to be located on site HOW
and a station on site NAN at Bikini Atoll. To provide this interrelation to first order. procedures,would require an extensive
horizontal control survey including a first order base line on
HOW and a new lagoon station west of HOW. The following recommen-
ded procedures are based on modification of this requirement to
specify that the inter-relation be determined to within a tolerance
of13255000, but eliminating the requirement for first order proceauree
(1)
HorizontalControl
An evaluation of the existing network
indicates that due to the strength of the original survey
and the relatively small area involved,
horizontal inter-
relation within the tolerance of 1:25, 000 can be
accomplished in the following manner.
This is on the
assumption that stations Worth HOW, South HOW and NAN
have not been disturbed.
(a)
An adjustment by the method of least squares will
be applied to the original 1953 survey, and to the
1955 expansion survey. This will determine the
most probable values for the stations of the network,
including the stations on HOW and NAN. The closing
error of the original 1953 network, before adjust-
ment, was better than 1:70,000 and a very low probable error was determined tor the base line. With
this strength it is safe to assume that the adjusted
values for HOW and NAN will meet requirements of
1:25,000.
(b)
The horizontal location of the primary working point
on HOW will be determined by observing the triangle
WP - North HOW - South HOW to first order procedures.
(c)
The additional working points on HOW will be located
by first order traverse procedures from these
stations. The working point for the station on NAN
will be located by the same procedures in reference
to triangulation station NAN.