Translation of relevant parts:

Question: “... we want to ask Moron shlito ...... although with regard to the Sha’aloh of Reshus Horabim min Hatorah they have the Shtioh of Moron HaChazon Ish who is lenient, however regarding other Sha’alos such as the requirement that the vertical poles should be inside the Mechtizos – which was not done in this case – and also regarding Karfifos [i.e. areas not deemed habitable according to Halocho] which are larger than a Beis Sosayim and not fit for walking, which this Eruv has it in many cases; and on these matter the Shitoh of Moron HaChazon Ish is not lenient; and with regard to renting Reshus where in our days there is no Sar Ho’ir [i.e. the Sar Ho’ir does not posess the legal power to enter dwelling houses at all times without preconditions], and further Chashoshos. For this reason we want to ask whether we should us this Eruv?

Answer: The Chazon Ish was indeed meikel that there is no [Reshus Horabim] De’orayso issue if the street is “okum”. But in all Chashoshos Derbaonon he was not lenient at all. On the contrary he was very stringent here in Bnei Brak as is well-known.

Chaim Kanievski

Note:

a] The requirements of not having Karfifos and the Din of renting Reshus from Nochrim are miderabonon, the question of classifying the streets as Reshus Horabim min Hatorah is a de’orayso issue.

b] Previously a Shoiel shlito had addressed a two letters to Hag. R. Kanievski. In the first letter he reported that the G.G. Eruv was invalid according to the Chazon Ish measurements and in such a state that it could break down at any time. Hag. R. Kanievski replied encouraging him to repair the Eruv. [Note: It is a little surprising that such an Eruv was launched with “full confidence”. Either those who launched it did not know the state of the Eruv or they did not know the idea of “full confidence”…]

In the second letter the Shoiele shlito asks: After working on the North West London Eruv day and night with numerous repairs it is now on a very high standard of Hidur. “The Eruv is now kosher lekatchilo in an excellent way according to Moron HaChason Ish zatzal.” They want to ask whether they should publicize this in order to remove from those who carry the ‘La’az’ as if they are Mechalelei Shabbos Befahesyo rachamono litzlon, and they are humiliated in public for this.

Hag. R. Kanievski replied: ראוי לפרסם .

The Shoiel in the third letter stresses that in fact this Eruv suffers from a number of Derabonon-problems. He suggests that thus the Eruv is far removed from being excellent or indeed even kosher according to the Chazon Ish. Hag. R. Kaievski replies that in the Chazon Ish’s view these invalidate an Eruv. [Of course these requirements do not apply only to an Eruv in Bnei Brak but all over the world including London.]