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Email: To make ice you need water

23-Nov-2012 [8118]

• Jutta Mason to Jim Hart with clarification of facts

-------- Original Message --------
Subject: To make ice you need water
Date: Fri, 23 Nov 2012 14:18:28 -0500
From: Jutta Mason <>
To: Jim Hart <>
CC: Richard Ubbens <>, James Dann <>, Ana Bailao <>, Nick Gallant <>

Dear Mr.Hart,

Thank you for responding to my two e-mails. There are several errors of fact contained in your response and in the previous response from Mr. Ubbens:

1. Re Harbourfront has "quite new" compressors: Harbourfront confirmed this morning that their compressors are the original ones from 1983 (older than any city compressors). I believe they installed new chillers a few years ago. 2. Brine and other coolants being "less efficient" than direct-ammonia: The city has one direct-ammonia plant left, which makes worse ice than the brine plants. Brine is highly efficient, as long as it circulates through a great big tank of ammonia -- and that's the cooling system at most of the city rinks, and at Harbourfront. 3. Mr.Ubbens' claim that staff have tried my "strategies" for the past two seasons: As far as we know from our rink visits, and conversations with various on-site staff at those rinks, there have been no recent overnight floods of rinks for start-up with the exception of City Hall, Dufferin Rink, and perhaps Rennie Rink. Please ask your staff to send us the locations, dates and times of overnight floods that we missed.

The fact is that to make ice one needs to put down water. Taking Dufferin Rink as an example, the first flood done by staff was not until 59 hours after the compressors were turned on. Yet 10 hours after the compressors went on, our test patches froze in ten minutes.

The total number of floods needed to make good ice at compressor-cooled rinks during any weather is roughly 15, plus roughly 4 zamboni sessions (see: Fundamentals of Ice Making). That can be done in 5 days, or 4 days if two shifts of staff are assigned to work when it actually gets dark (there are about 13 hours of darkness in mid-November). We noted that yesterday, five Local 416 staff came to lay the mats at Dufferin in the morning -- if that shift was assigned in the evening, and (two) staff laid out the mats from 3 until 6 and then began flooding after 7, the two back-to-back shifts would cost no extra.

Thank you for thanking me for my continued interest and advice. Advice is only helpful if someone attends to it. Having staff at rinks and not making ice is a serious waste of manpower and public resources. Would you like to come and see for yourself? You might want to take in two rinks, for comparison -- Glen Long Rink, up the street from Dufferin Rink, is a good spot to visit as well. By yesterday morning, Glen Long showed every sign of having been washed down but not flooded at all. Are they following your direction to "focus their attention on getting our rinks open"?

I am happy to meet you and anyone else you want to bring, on-site, any time before Wednesday afternoon.

Jutta Mason