diff --git a/AsbCloudApp/Data/SimpleTimezoneDto.cs b/AsbCloudApp/Data/SimpleTimezoneDto.cs
index e878bacf..5d2e1f8f 100644
--- a/AsbCloudApp/Data/SimpleTimezoneDto.cs
+++ b/AsbCloudApp/Data/SimpleTimezoneDto.cs
@@ -3,29 +3,29 @@ using System;
 namespace AsbCloudApp.Data
 {
     /// <summary>
-    /// ��������� ����
+    /// временная зона
     /// </summary>
     public class SimpleTimezoneDto
     {
         /// <summary>
-        /// �������� � ����� ������������ UTC
+        /// смещение в часах относительно UTC
         /// </summary>
         public double Hours { get; set; }
 
         /// <summary>
-        /// ������������� ������� ����
+        /// идентификатор часовой зоны
         /// </summary>
         public string? TimezoneId { get; set; }
 
         /// <summary>
-        /// ������ �� ���������������
+        /// запрет на переопределение
         /// </summary>
         public bool IsOverride { get; set; }
 
         /// <summary>
-        /// �������� �������� �����
+        /// Смещение часового пояса
         /// </summary>
-        public TimeSpan Offset { get => TimeSpan.FromHours(Hours); }
+        public TimeSpan Offset => TimeSpan.FromHours(Hours);
 
         /// <inheritdoc/>
         public override bool Equals(object? obj)
diff --git a/AsbCloudApp/Exceptions/ArgumentInvalidException.cs b/AsbCloudApp/Exceptions/ArgumentInvalidException.cs
index 5db63313..641f18ce 100644
--- a/AsbCloudApp/Exceptions/ArgumentInvalidException.cs
+++ b/AsbCloudApp/Exceptions/ArgumentInvalidException.cs
@@ -14,6 +14,7 @@ namespace AsbCloudApp.Exceptions
         /// </summary>
         public IDictionary<string, string[]> ErrorState { get; } = null!;
 
+        // TODO: swap arguments, inherit from ArgumentException
         /// <summary>
         /// конструктор
         /// </summary>
diff --git a/AsbCloudApp/Repositories/IWellOperationRepository.cs b/AsbCloudApp/Repositories/IWellOperationRepository.cs
index 8cb313ac..ff3bfb8e 100644
--- a/AsbCloudApp/Repositories/IWellOperationRepository.cs
+++ b/AsbCloudApp/Repositories/IWellOperationRepository.cs
@@ -13,10 +13,12 @@ namespace AsbCloudApp.Repositories
     /// </summary>
     public interface IWellOperationRepository
     {
+        //TODO: replace all references
         /// <summary>
         /// список названий операций
         /// </summary>
         /// <returns></returns>
+        [Obsolete("use IWellOperationCategoryRepository.GetCategories(bool includeParents)")]
         IEnumerable<WellOperationCategoryDto> GetCategories(bool includeParents);
 
         /// <summary>
diff --git a/AsbCloudDb/EFExtensionsExceptionHandling.cs b/AsbCloudDb/EFExtensionsExceptionHandling.cs
index 77b8fe07..aa1996b5 100644
--- a/AsbCloudDb/EFExtensionsExceptionHandling.cs
+++ b/AsbCloudDb/EFExtensionsExceptionHandling.cs
@@ -27,6 +27,7 @@ namespace AsbCloudDb
         private static void TryConvertPostgresExceptionToValidateException(PostgresException pgException)
         {
             if (pgException.SqlState == PostgresErrorCodes.ForeignKeyViolation)
+                // TODO: replace ArgumentException by new Exception
                 throw new ArgumentException(pgException.Message + "\r\n" + pgException.Detail, "dtos");
         }
     }
diff --git a/AsbCloudInfrastructure/Repository/ChangeLogRepositoryAbstract.cs b/AsbCloudInfrastructure/Repository/ChangeLogRepositoryAbstract.cs
index ba32907c..f9265ba8 100644
--- a/AsbCloudInfrastructure/Repository/ChangeLogRepositoryAbstract.cs
+++ b/AsbCloudInfrastructure/Repository/ChangeLogRepositoryAbstract.cs
@@ -145,7 +145,7 @@ public abstract class ChangeLogRepositoryAbstract<TDto, TEntity, TRequest> : ICh
     public async Task<int> ClearAndInsertRange(int idUser, TRequest request, IEnumerable<TDto> dtos, CancellationToken token)
     {
         var result = 0;
-        var transaction = await db.Database.BeginTransactionAsync(token);
+        using var transaction = await db.Database.BeginTransactionAsync(token);
         result += await Clear(idUser, request, token);
         result += await InsertRange(idUser, dtos, token);
         await transaction.CommitAsync(token);