Kind of memory management issue

[airsize]

I have a PC with 8GB ram, capable to run the game.
Every time before I run the game, I check there still have about 4 GB memory for CSL to use.
I also close all unnecessary program before launching the game.
After starting a new game or loading a save. The game runs fine on my pc.
But the game will use all remaining memory until it reach 100% memory usage in minutes.
Then just CTD.
I have experienced it many times and tried to figure out.
The game's memory management seems like the main cause.
Here is my desktop specification.

Processor Information:
Vendor: GenuineIntel
CPU Family: 0x6
CPU Model: 0x17
CPU Stepping: 0xa
CPU Type: 0x0
Speed: 2666 Mhz
4 logical processors
4 physical processors
HyperThreading: Unsupported
FCMOV: Supported
SSE2: Supported
SSE3: Supported
SSSE3: Supported
SSE4a: Unsupported
SSE41: Supported
SSE42: Unsupported

Network Information:
Network Speed:

Operating System Version:
Windows 7 (64 bit)
NTFS: Supported
Crypto Provider Codes: Supported 311 0x0 0x0 0x0

Video Card:
Driver: AMD Radeon HD 6800 Series

DirectX Driver Name: aticfx32.dll
Driver Version: 9.12.0.0
DirectX Driver Version: 8.17.10.1172
Driver Date: 19 Dec 2012
OpenGL Version: 4.2
Desktop Color Depth: 32 bits per pixel
Monitor Refresh Rate: 60 Hz
DirectX Card: AMD Radeon HD 6800 Series
VendorID: 0x1002
DeviceID: 0x6738
Number of Monitors: 1
Number of Logical Video Cards: 1
No SLI or Crossfire Detected
Primary Display Resolution: 1440 x 900
Desktop Resolution: 1440 x 900
Primary Display Size: 20.00" x 12.52" (23.58" diag)
50.8cm x 31.8cm (59.9cm diag)
Primary Bus Type Not Detected
Primary VRAM: 1024 MB
Supported MSAA Modes: 2x 4x 8x

Sound card:
Audio device: ??z (Realtek High Definition A

Memory:
RAM: 8190 Mb

 

[Anttonilla]

My game has crashed three times due to the lack of memory, too. Once while playing with water physics, once in game and once in asset editor.

My specs:
AMD FX-6300
Team Group Vulcan 8GB 2400MHz
ASUS GTX 660 OC
Windows 8.1 64bit