Although SEA is mentioned in high-level policy discourses that
state no less that it is one of the environmental measures to be
adopted (such as, for example, in the official statements of the Council
of Ministers to the National Assembly on 29 December 2008, the 10th
NESDP passed by the cabinet, and the National Environmental Quality
Management Plan 2007–2011 [NESDB, 2007; ONEP, 2007]), there is
no distinct legislation directly supporting SEA implementation. The
wording in Part 4 Section 46–51 of the Enhancement and Conservation
of National Environmental Quality Act B.E. 2535 or NEQA specifies
the enforcement of EIA, but not SEA. Indeed, currently, NEB has
approved and suggested the use of the SEA guideline for government
agencies' policy and planning process as appropriate. But this means
that SEA's implementation is on a voluntary basis, without a specific
penalty for failure to do so. Furthermore, although NEB is authorized
to exercise the necessary measures to conserve the environmental
quality according to National Environmental Quality Act (NEQA), the
power of enforcing the measures is ambiguous and not clearly stated
in the law.