NATIONAL POWER CORPORATION, PETITIONER, VS. HEIRS OF GREGORIO RAMORAN, NAMELY: DELFIN R. PINEDA, ESPERANZA PINEDA MAGPALI, DIGNA PINEDA ARZADON, CARIDAD R. PINEDA, IMELDA ZIAPNO, TERESITA PINEDA DELFIN, ESTER R. PINEDA, FE Y. UZON, PACENCIA ERFE VERSOZA, IMPRESSION V. CLEMENTE, ALL REPRESENTED BY DELFIN R. PINEDA, ATTORNEY-IN-FACT, RESPONDENTS