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Messages - AlexB

Pages: 1 2 [3] 4 5 ... 195
31
General Talk / Re: Pedal Power- questions on Mirage Drive performance
« on: July 25, 2020, 02:34:23 PM »
If this has been covered, somebody please paste the thread right on in...

A post about mirage drive wear/tear got me wondering about what peopleÂ’s experiences have been with drive/hull performance, specifically speed and endurance. That said, there are a lot of ways this conversation could go.

IÂ’ve always used a Hobie Outback as my primary vessel. IÂ’ve paddled a few Sit Inside hulls and have pedaled a Hobie Classic and Sport, but not really enough to be able to compare to my Outback effectively.

So I guess a few key stats of interest would include:
Top speed-
I can manage about 6.5 mph for very short bursts in FAC conditions, with no current or wind.

Sustained speed for covering distances-
About 5mph in perfect conditions for up to 1.5 hours or so. I can go at trolling speed (1-3 mph for an entire day if I have food/water)

Max mileage (again in perfect conditions)-
The most IÂ’ve done in a day was about 20 miles on lake Don Pedro one summer. Average trip is probably around 10 miles. I feel pretty burned and have wicked soreness in my knees at the end of a full day on the water.

If you have some figures you would like to share, for whatever you are paddling or pedaling, it would be sort of fun to have some data for comparison. I know the Outback is a barge, so those of you in RevoÂ’s or hulls with less drag and draft probably have way higher numbers. Looking forward to checking out any replies!
My speed/endurance “stats” are very similar to yours, and my primary kayak is also an Outback. I’ve done something north of 20 miles in a day - FF battery died at about 19.5 miles then I trolled a bit more before pedaling the ~2 miles back to Bolinas from the salmon grounds. I was definitely wiped out and sore after that. Most trips are 15 miles or less I’d say.

That said, I usually don’t venture more than about 4-5 miles from my launch spot unless I know I’ll be able to ride the wind/current home.


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32
Gearing Up and Rigging Up / Re: Mirage Drive Repairs
« on: July 24, 2020, 02:53:47 PM »
Yeah, I’ve also gone through a few idler pulleys, cables/chains, etc... It’s a bummer how much they cost but at least they’re relatively easy to replace.


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33
General Talk / Re: Usal beach area
« on: July 24, 2020, 12:36:08 PM »
I love camping out at Usal, but you’re right... It’s a very exposed beach. And as you know, if anything were to happen out there you’d largely be on your own.

If you head out there, stay safe!


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34
Fish Talk / Re: ID help of jellyfish thing.
« on: July 23, 2020, 03:07:12 PM »
I've seen some of that before, but 'twas nowhere near that big...
What you saw might have been a cluster of squid eggs?


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35
Not stoked on the build quality of the Power Box, and definitely not stoked on their customer service. Long story short, I'm back to square one and will likely just build my own box...

36
Gearing Up and Rigging Up / Dakota Lithium - BUYER BEWARE!
« on: July 22, 2020, 09:34:09 AM »
Just a heads up... If you're thinking about buying a battery or "Power Box" from Dakota Lithium, I suggest you reconsider. Their customer service is piss poor... I should have listened to another review that said the same thing, but I didn't. Live and learn...

I placed an order for a Power Box 10 back on June 11. UPS took almost 3 weeks to deliver the package, and during that time I sent several emails to Dakota asking them to please reach out to UPS for updates (UPS isn't taking calls from package recipients during the pandemic, but I assumed they would talk to the shipper). I kept getting BS one sentence replies from their "customer service" guy (Patrick Rose) basically saying he couldn't help me because he wasn't in the "shipping department". When I finally convinced him to ask the shipping department, they weren't helpful either.

When the product finally did arrive, I was not at all impressed. The box feels flimsy and I would be very surprised if it was waterproof. It's made from thin plastic with plastic hinges. The battery is just plopped in there with a couple loose pieces of foam around it. Basically the battery is just loose in there and flops against the wiring and electronics. The switches and binder posts look/feel cheap. And to top it off, one of the little rubber boots that's supposed to keep water out of the switches was not installed properly and clearly wasn't at all waterproof.

I contacted Dakota on 7/2 and let them know about the issue with the (not waterproof) switch. They said they would send me a replacement Power Box and a shipping label to return the old one.

Two weeks later I had not received any further emails or tracking info, so I emailed to ask what was up. Patrick said it was "on the ship list and leaving shortly". Here we are 20 days since he said he'd ship a replacement and it still hasn't happened. I've gotten 4 or 5 more replies from Patrick saying it will ship "shortly".

Long story short, I am now waiting on a refund and a return shipping label to send this POS back to Dakota.

Should have gone with my gut and just made my own "Power Box" from scratch using better materials...


37
I like the FG knot with Rizutto finish. Probably wouldn’t tie that one on the water though...


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38
General Fishing Tips / Re: Salmon hook question
« on: July 14, 2020, 01:55:19 PM »
“...just make sure you're always under your own power or the power of a motor (if you're not a kayaker).”

Ha! That one might ruffle a couple feathers...


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39
General Talk / Re: Sometimes I forget how filthy the bay is.
« on: July 09, 2020, 01:32:34 PM »
If you ever feel like getting grossed out, check out the Water Board’s GeoTracker tool online. You can search any area of California and see a map with most (not all) contaminated sites identifies. You can also find information about what was spilled, when, and what’s been done to investigate and/or remediate it.

The state is just peppered with sites... Old gas stations, old dry cleaners, old manufacturing hubs, semiconductor industry, etc, etc, etc... Humans have really made a mess of things.

https://geotracker.waterboards.ca.gov


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40
General Talk / Re: Sometimes I forget how filthy the bay is.
« on: July 09, 2020, 01:28:42 PM »
Groundwater discharges into the bay, correct?
Correct.


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41
General Talk / Re: Sometimes I forget how filthy the bay is.
« on: July 09, 2020, 09:24:06 AM »
AlexB that's really fascinating appreciated you sharing that. 

Q: the removed source material, where does THAT end up??  Hopefully not in the south bay  :smt044
The stuff we sucked out of the ground during ERH treatment was just filthy... It was a mix of HOT groundwater, steamy soil vapor, petroleum hydrocarbons (primarily a compound called stoddard solvent - really smelly but not terribly toxic), volatile organic compounds like PCE/TCE/DCE/VC/etc, and smelly black biomass (basically the dead bodies of bacteria that had been munching on this mess until we boiled them alive).

This filthy mix then passed through an extravagant treatment system. First the mix was cooled down to a reasonable temperature, which allowed us to separate the liquid phase (heavily contaminated groundwater with a layer of hydrophobic floating chemicals on top) from the vapor phase (air and chemical vapors). The liquid phase first went through a "product separator" to remove the "free phase" chemicals (the floating portion), clay bed filter to remove small droplets of chemicals, air stripper to remove dissolved volatile compounds, activated carbon remove what the air stripper missed, and finally micro filtered to remove any contaminated activated carbon "dust" that leaked from the carbon beds. After all that, the water was quite clean, and we were able to discharge it to the EBMUD sanitary sewer system (we had a permit to do this, and were required to test the water frequently).

The vapor phase was treated in a similar manner using several very large activated carbon filters. Rather than hauling the "spent" carbon off site as a waste material each time it reached it's treatment capacity, we "regenerated" the carbon every few days by passing steam through it to strip the contaminants from the carbon. What we were left with was ~300 gallon tote after tote after tote of essentially purified/distilled chemicals we had removed from the ground. This stuff looked a lot like vegetable oil, but it would knock you right on your ass if you were to smell it (all staff working directly with that stuff wore respirators at all times).

Long story short, all of the funk we pulled from the ground was separated from the groundwater and soil vapor, concentrated into a pure liquid form, and transported to a Clean Harbors facility Aragonite, Utah where it was blended with other flammable liquieds/fuels and incinerated to generate energy. 

The whole time this was going on, we were monitoring the air quality around the perimiter of the site in real time using a mobile on-site lab (GS/MS) plumbed to ~15 different air sampling points. This ensured that we didn't put the surrounding community at risk.

42
General Talk / Re: Sometimes I forget how filthy the bay is.
« on: July 08, 2020, 03:29:32 PM »
Quote
I'm not saying the Bay isn't filthy, just that the AMCO site really isn't part of that equation.

It’s cool to hear some first hand info, thanks.

I hope you don’t consider it a reflection of your hard work or expertise If I remain skeptical that 30 years of sloppy chemical handling and transportation can be cleaned up completely in just a few years, and somehow never reached bay waters.
I think a healthy dose of skepticism is a good thing, especially if your health and well being are in question. No offense taken there. 

There were many different chemicals handled at the AMCO facility back in the day, but the primary "risk drivers" in this case were chlorinated solvents called tetrachloroethene (PCE), trichloroethene (TCE) and the various "daughter products" that form as they degrade (cis-1,2-DCE and vinyl chloride to name a couple). PCE and TCE were commonly used for all kinds of things from dry cleaning to parts degreasing to semiconductor manufacturing. They're still used in some industries, but at least they are heavily regulated and monitored at this point.

Thankfully, there is a subset of bacteria (dehalococcoides) that, given the right living conditions, can degrade these chemicals "in-situ" through a process called "reductive dechlorination". PCE is just two carbons joined by a double bond and surrounded by four chlorines. TCE is the same, but it has three chlorines and one hydrogen. As the bacteria strip one chlorine from the compound at a time and replace it with hydrogen, it degrades from PCE (four chlorines) to TCE (three chlorines) to DCE (two chlorines) to vinyl chloride (one chlorine) and finally to ethene (no chlorines, only hydrogens). Ethene is not terribly harmful and also degrades very quickly in the subsurface.

When we studied the results of groundwater samples collected on site and various distances downgradient, we could clearly see that this process was occuring. PCE was largely constrained to the site itself. TCE extended slightly further. cis-1,2-DCE slightly further, then vinyl chloride, etc. None of them had traveled far from the site.

Google "reductive dechlorination" if you're curious. I think it's pretty fascinating.

Don't get me wrong. The site definitely has not been "cleaned up completely", but the nature and extent of the contamination has been well defined and the health risks have largely been mitigated. We removed the vast majority of the source material, and the biological processes are doing a good job of containing what's left and degrading it long before it reaches the Bay.

Someone mentioned Alameda Point. I've worked on that project, too, and it's a whole other ball o' wax....

43
General Talk / Re: Sometimes I forget how filthy the bay is.
« on: July 07, 2020, 02:25:52 PM »
I'm not saying the Bay isn't filthy, just that the AMCO site really isn't part of that equation.

44
General Talk / Re: Sometimes I forget how filthy the bay is.
« on: July 07, 2020, 02:04:42 PM »
Ha! It's a trip seeing this show up on NCKA...

I was actually the project engineer on site during the latest cleanup effort at the AMCO Chemical Superfund site, but I have since moved on to a different consulting firm that isn't involved in that project.

That site is indeed a nasty one (much less so now that we removed something like 40,000 lbs of mixed petroleum and VOCs from the soil and groundwater), but I can assure you that the contamination from AMCO is not making it's way into SF Bay. There are biological processes at play that are degrading these chemicals "in-situ" as the migrate off site, and they haven't reached anywhere near the Bay. Also, we removed the bulk of the source material. We recovered the chemicals using a process called Electrical Resistance Heating (ERH) - basically we passed so much electricity through the soil and groundwater that it heated up beyond the boiling point of the contaminants. We kept it hot like that for about 10 months while we recovered all the contaminants that "boiled off" using an extraction and treatment system plumbed to something like 70 recovery wells.

The info on that Wiki page is very outdated....

45
Recipes / Re: Best tasting rockfish?
« on: July 06, 2020, 08:49:04 AM »
When it comes to rockfish, I feel like the quality and flavor of the flesh it has a lot more to do with the size/age of the fish and what it’s been eating than the species.

Some day when it’s cool to gather in groups again it would be fun to do a true blind taste test with various sizes of various species.


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