From MEMRI Special Dispatch Series - No. 2006, July 29, 2008:
On July 29, 2008, the Kuwaiti daily Al-Siyassa reported that, according to "highly reliable sources," Iranian authorities had begun construction of a secret nuclear reactor in the Al-Zarqan region close to the city of Ahwaz in southwest Iran, on the Iran-Iraq border.
The paper said that according to sources, Iran was working to distance its nuclear installations from international oversight. The English version of the report, published in the Kuwaiti Arab Times, said, "Disclosing [that] Tehran directed international A-bomb inspectors to other places, sources warned [that] the project poses a very serious threat to international security."
Also according to the sources, the International Atomic Energy Agency (IAEA) did not know about this site at all, since it was not included in negotiations with Iran in Geneva held in early July.
According to the report, the sources said that during 2000-2003, Iran expropriated the lands and homes of thousands of Arab citizens from the Al-Zarqan region, destroying homes of thousands of Arab citizens from the Al-Zarqan region....
Follow these links for a summary of the Al-Siyassa report,  and from its English  version in the Kuwaiti English-language daily Arab Times, which was also published July 29, 2008.
... a letter dated April 7, 2008 from the office of the assistant of IRGC commander in Al-Ahwaz city Brig. Hassan Jalaliyan, marked "highly confidential," to Mohammed Kayafir, manager of the Mehab Qudus Company for Construction and Supervision, which is building the reactor. The following is a translation of the letter:
"From the IRGC [Iranian revolutionary Guard Corps] Commander in the city of Al-Ahwas to the director in charge at the Mehab Qudus company for Construction and Supervision Mr. Mohammed Kayafir
"Re: The nuclear reactor at Al-Zarqan
"I thank you for the good services of the Mehab Qudus company, and at the same time I must remind you of the following items:
"1. All construction materials must be transported from the warehouses to the construction site in top secrecy.
"2. As part of the doctrine of caution, we reiterate yet again that during the transport of all required materials, you must ensure that this [transport] does not arouse the suspicions of any citizen in the region through which you are moving.
"3. In general, it is absolutely forbidden to hire any Arabic speakers or any citizen from Khozestan in the framework of the 'Al-Zarqan Nuclear Reactor' construction project. You must ensure that all manpower, including the driver, the accountant, the warehouse manager, the laborer, the technician, or the guard, comes from the northern provinces.
"In conclusion, we say yet again that all the construction work in this project must be carried out under absolute secrecy.
"From the aide to IRGC commander in the city of Al-Ahwaz, Hassan Jalaliyan."
....An Ideal Place to Build a Nuclear Reactor - The Local Residents Can Serve as a Human Shield
..."The site is more suitable for building a nuclear reactor than Bushehr, which is close to American bases." ...a nuclear power plant under construction at Darkhovin is in an open area on the main road between Ahwaz and Abadan - while the "Al-Zarqan nuclear reactor is in the middle of very highly populated areas, making it a very difficult target due to a possibility that the Iranian authorities will use civilians as human shields."
On January 31, 2008, the Iran Daily wrote that Iranian Atomic Energy Organization deputy head Ahmad Fayyazbakhsh had said that the nuclear power plant at Darkhovin, in southwestern Iran, would become operational in 2016.  ...
 Al-Siyassa (Kuwait), July 29, 2008,
 Arab Times (Kuwait), July 29, 2008, http://www.arabtimesonline.com/kuwaitnews/pagesdetails.asp?nid=20349&ccid=9 (the text has been lightly edited for clarity).
 Iran Daily (Iran), January 31, 2008, http://www.iran-daily.com/1386/3052/pdf/i2.pdf.