The value 0.00007136 being displayed as 7.136E-05 is due to how SQL Server (and many other systems) format floating-point numbers. This is a display formatting issue, not a data accuracy issue.
DROP TABLE IF EXISTS t1
GO
CREATE TABLE t1 (i INT, j FLOAT)
GO
INSERT INTO t1 VALUES (1, 0.00007136)
GO
SELECT j, CAST(j AS NUMERIC(10,8)),
CAST(j AS DECIMAL(10,8)),
FORMAT(j, '0.00000000')
FROM t1