Send an extra 10 L bulk sample for spiking at the Cryptosporidium laboratory
concurrent with the 1st and 21st routine monitoring sample collections and
again with every 20 samples if more than 40 source water samples are
collected. Coordinate the collection of matrix spike samples with your laboratory.
Matrix spike samples should be collected from the same location and at the
same time as the associated routine sample. The matrix spike sample and
routine sample should be the same volume. Label the cubitainer with the
following information using a waterproof pen: PWSID, facility name, and sample
collection date. Chill the sample as soon as possible to between 1° and 10°C
before shipment.
10-L Matrix Spike Sample
Follow instructions for collecting a
10-L bulk water sample given on
previous panel.
Matrix Spike Samples Greater than 10-L
Either ship the entire matrix spike volume
as a bulk sample to the laboratory to be spiked and analyzed, OR filter all
but 10 L of the matrix spike sample at your utility and collect the remaining
10 L as a bulk sample. Chill both the filter and bulk sample as soon as possible
to between 1° and 10°C before shipment. Clearly label both the filter and
bulk sample as comprising 2 parts of a single sample.