Use SqlBulkCopy in SQL CLR

using System;
using System.Data;
using System.Data.SqlClient;
using System.Data.SqlTypes;
using Microsoft.SqlServer.Server;
using System.Security.Principal;

public partial class StoredProcedures
{
    [Microsoft.SqlServer.Server.SqlProcedure]
    public static void clr_usp_MoveBulkData()
    {
        DataTable source = new DataTable();

        using (SqlConnection cn = new SqlConnection("context connection=true"))
        {
            string sql = "SELECT {columnspec} FROM Source_TableName;";
            cn.Open();
            SqlCommand cmd = new SqlCommand(sql, cn);
            SqlDataAdapter da = new SqlDataAdapter(sql, cn);
            da.Fill(source);
            cn.Close();
        }

        WindowsIdentity currentIdentity = SqlContext.WindowsIdentity;
        WindowsImpersonationContext impersonatedIdentity = currentIdentity.Impersonate();

        try
        {
            using (SqlConnection conn = new SqlConnection("Server=ServerName;Database=DestinationDatabase;Integrated Security=true"))
            {
                conn.Open();
                SqlBulkCopy bc = new SqlBulkCopy(conn);
                bc.DestinationTableName = "DestinationTable";
                bc.BatchSize = source.Rows.Count;
                bc.WriteToServer(source);
                conn.Close();
            }
        }
        finally
        {
            impersonatedIdentity.Undo();
        }
    }
};