  The probability of simultaneous occurence of at least k spanning clusters has
been studied by Monte Carlo simulations on the 2D square lattice at the bond
percolation threshold $p_c=1/2$. It is found that the probability of k and more
Incipient Spanning Clusters (ISC) has the values $P(k>1) \approx 0.00658(3)$
and $P(k>2) \approx 0.00000148(21)$ provided that the limit of these
probabilities for infinite lattices exists. The probability $P(k>3)$ of more
than three ISC could be estimated to be of the order of 10^{-11} and is beyond
the possibility to compute a such value by nowdays computers. So, it is
impossible to check in simulations the Aizenman law for the probabilities when
$k>>1$. We have detected a single sample with 4 ISC in a total number of about
10^{10} samples investigated. The probability of single event is 1/10 for that
number of samples.
