great job providing the same DDL and Data!

maybe i'm missing the hard part of the question and overlooking the obvious,it, but does this do what you want? a simple union, ten times for each value/date pair in the table?

SELECT [pk_value], ER_1,ER_1_ExpDate FROM [dbo].[ERFiles] UNION ALL

SELECT [pk_value], ER_2,ER_2_ExpDate FROM [dbo].[ERFiles] UNION ALL

SELECT [pk_value], ER_3,ER_3_ExpDate FROM [dbo].[ERFiles] UNION ALL

SELECT [pk_value], ER_4,ER_4_ExpDate FROM [dbo].[ERFiles] UNION ALL

SELECT [pk_value], ER_5,ER_5_ExpDate FROM [dbo].[ERFiles] UNION ALL

SELECT [pk_value], ER_6,ER_6_ExpDate FROM [dbo].[ERFiles] UNION ALL

SELECT [pk_value], ER_7,ER_7_ExpDate FROM [dbo].[ERFiles] UNION ALL

SELECT [pk_value], ER_8,ER_8_ExpDate FROM [dbo].[ERFiles] UNION ALL

SELECT [pk_value], ER_9,ER_9_ExpDate FROM [dbo].[ERFiles] UNION ALL

SELECT [pk_value], ER_10,ER_10_ExpDate FROM [dbo].[ERFiles]