CREATE TABLE table_9429 ("CERCLIS ID" CLOB, "Name" CLOB, "County" CLOB, "Proposed" CLOB, "Listed" CLOB, "Construction completed" CLOB, "Partially deleted" CLOB)

When was the site listed 03/31/1989 in rockingham county proposed?
SELECT "Proposed" FROM table_9429 WHERE "Listed" = '03/31/1989' AND "County" = 'rockingham'
SELECT "Proposed" FROM "table_9429" WHERE "County" = 'rockingham' AND "Listed" = '03/31/1989'