OpenXML - ¿hay una manera de quitar el lavado característica de Microsoft Word marca de agua?

Al agregar una marca de agua a la cabecera del documento de word, automáticamente se añade la opacidad a ella. Quiero eliminar la opacidad y al comprobar en el Microsoft Word, me enteré de que puede ser eliminado mediante la desactivación de la opción de Lavado de. Este puede ser eliminado mediante el OpenXML?

He seguido las marcas de agua de los códigos a continuación:

using System.IO;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using DocumentFormat.OpenXml.Packaging;
using DocumentFormat.OpenXml.Wordprocessing;
using DocumentFormat.OpenXml;
using V = DocumentFormat.OpenXml.Vml;
using System.Diagnostics;

namespace WindowsFormsApplication3
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            using (WordprocessingDocument package = WordprocessingDocument.Open(@"C:\Users\*****\****.docx", true))
            {
                InsertCustomWatermark(package, @"C:\Users\*******\****.jpg");
            }
        }

        private void InsertCustomWatermark(WordprocessingDocument package, string p)
        {
            SetWaterMarkPicture(p);
            MainDocumentPart mainDocumentPart1 = package.MainDocumentPart;
            if (mainDocumentPart1 != null)
            {
                mainDocumentPart1.DeleteParts(mainDocumentPart1.HeaderParts);
                HeaderPart headPart1 = mainDocumentPart1.AddNewPart<HeaderPart>();
                GenerateHeaderPart1Content(headPart1);
                string rId = mainDocumentPart1.GetIdOfPart(headPart1);
                ImagePart image = headPart1.AddNewPart<ImagePart>("image/jpeg", "rId999");
                GenerateImagePart1Content(image);
                IEnumerable<SectionProperties> sectPrs = mainDocumentPart1.Document.Body.Elements<SectionProperties>();
                foreach (var sectPr in sectPrs)
                {
                    sectPr.RemoveAllChildren<HeaderReference>();
                    sectPr.PrependChild<HeaderReference>(new HeaderReference() { Id = rId });
                }
            }
            else
            {
                MessageBox.Show("alert");
            }
        }
        private void GenerateHeaderPart1Content(HeaderPart headerPart1)
        {
            Header header1 = new Header();
            Paragraph paragraph2 = new Paragraph();
            Run run1 = new Run();
            Picture picture1 = new Picture();
            V.Shape shape1 = new V.Shape() { Id = "WordPictureWatermark75517470", Style = "position:absolute;left:0;text-align:left;margin-left:0;margin-top:0;width:415.2pt;height:456.15pt;z-index:-251656192;mso-position-horizontal:center;mso-position-horizontal-relative:margin;mso-position-vertical:center;mso-position-vertical-relative:margin", OptionalString = "_x0000_s2051", AllowInCell = false, Type = "#_x0000_t75" };
            V.ImageData imageData1 = new V.ImageData() { Gain = "19661f", BlackLevel = "22938f", Title = "水印", RelationshipId = "rId999" };
            shape1.Append(imageData1);
            picture1.Append(shape1);
            run1.Append(picture1);
            paragraph2.Append(run1);
            header1.Append(paragraph2);
            headerPart1.Header = header1;
        }
        private void GenerateImagePart1Content(ImagePart imagePart1)
        {
            System.IO.Stream data = GetBinaryDataStream(imagePart1Data);
            imagePart1.FeedData(data);
            data.Close();
        }
        private string imagePart1Data = "";
        private System.IO.Stream GetBinaryDataStream(string base64String)
        {
            return new System.IO.MemoryStream(System.Convert.FromBase64String(base64String));
        }
        public void SetWaterMarkPicture(string file)
        {
            FileStream inFile;
            byte[] byteArray;
            try
            {
                inFile = new FileStream(file, FileMode.Open, FileAccess.Read);
                byteArray = new byte[inFile.Length];
                long byteRead = inFile.Read(byteArray, 0, (int)inFile.Length);
                inFile.Close();
                imagePart1Data = Convert.ToBase64String(byteArray, 0, byteArray.Length);
            }
            catch (Exception ex)
            {
                Debug.Print(ex.Message);
            }
        }
    }
}