It seems that my hopes of finding the time and energy to update the blog regularly while working in Las Vegas have been quashed. We're now back in Tegucigalpa, where we're regrouping with Luis and tying up loose ends before heading back to Boston tomorrow, three days ahead of schedule. We spent a couple hours this morning wandering around downtown Tegucigalpa with Jorge and Camilo, two of the UPI students working with us. It was a huge change of pace from the small, rural villages we've become accustomed to. This afternoon we met with Jessica Castillo of PRONADERS (Programa Nacional de Desarrollo Rural Sostenible, the National Program for Sustainable Rural Development), the organization that provided funding for the Las Casetas treatment plant. From the sound of it, they are planning to begin renovating the system soon, once they have received final government approval.
Yesterday we spent most of the day driving from Las Vegas to Tegucigalpa and relaxing at the hotel, but first we stopped by AMUPROLAGO (the Association of Municipalities for the Protection of Lake Yojoa). There we spoke to Victor Ortiz and Oscar Carranza, who provided us with some valuable information pertaining to the nutrient loading in the lake, then we took us on a brief boat tour. Despite the greenness of the water in many areas (a result, according to AMUPROLAGO, of an overabundance of nutrients), it was gorgeous being out on the lake.
On Tuesday we got off to a fantastic start by making Kent hold a 4.5-gallon bucket under two streams of virtually untreated wastewater -- effluent from the Las Vegas Imhoff tank and collector system -- in order to get flow estimates for these systems. Needless to say, he did not enjoy it.
That afternoon we visited Aquafinca once again, where we spoke to Ernesto Vargas a second time. He provided us with some documentation on the different streams and rivers that flow into (and consequently pollute) Lake Yojoa.
Monday began with a brief meeting with Alejandra Gomez, environmental director for the AMPAC mine in El Mochito. We arranged for a tour of the mine's waste treatment facilities in the afternoon. In the meantime, we headed back to Las Vegas and met up with Santiago Hernandez, head of Las Vegas' water department, who showed us some of the septic tanks in El Mochito and San Juan. Overall, they're in pretty bad shape; apparently something like 90 percent of them have collapsed. There was some talk of plans to link these two towns up with Las Vegas' wastewater treatment facility, but considering the amount of work it's going to take just to get the Las Vegas Imhoff tank up to par to treat Las Vegas' wastewater, I don't think that's really feasible at this juncture.
At 2:30 we began our arranged tour of the AMPAC mine's treatment facilities. Effluent from the mine is of potential concern in terms of its impact on the water quality in Lake Yojoa, particularly when it comes to heavy metals. However, the company does seem to run a pretty tight ship when it comes to dealing with their waste. Wastewater is chemically treated before being either sent back to the mine (as fill) or to several tailings ponds, where sedimentation occurs. Basically, all of the solids are allowed to settle out, and the water that is then discharged into the river (which eventually flows into Lake Yojoa) is tested routinely to make sure all applicable standards are met. From what we were told, they consistently meet all required standards.
Here's what their newest tailings pond looks like, installed about two years ago:
Another interesting aspect of the mine was their "Orchidarium," where they grow plants to make up for those destroyed in the mining process.
And finally, we visited a spring that is a source of water for both the mine and Las Vegas.
And in terms of safety, it looks like the mine is doing pretty well overall. They've got a great big sign out front that displays the number of days without serious accidents in all of the various sectors:
The previous day, on Sunday, we revisited the Las Casetas plant. Heber provided us with a ladder, with which we were able to climb on top of and look inside the large tank. This gave us a much better idea of how the tank was intended to operate, although we still have some lingering questions, which hopefully will be answered by looking through the original plans for the plant, which we received from PRONADERS today.
While we were at Las Casetas, Heber also took us behind one of the restaurants to look at the failed collection tank. It was built below capacity and was unable to handle rising water levels in the lake.
Saturday's main event was revisiting the Imhoff tank in Santa Barbara, which we'd stopped by at one point the previous week. While we were there, Marvin and Jorge helped us map out the plant in detail, and Kent and I outlined the piping and brainstormed some suggestions for repairs and maintenance.
We also tracked down the effluent pipe to where it empties into an adjacent stream, in the hopes that we'd be able to take flow measurements there, but it turns out that it juts out over some steep and slippery rocks in such a way that it's nearly impossible to get to. Unfortunately, this little hitch kept us from being able to measure flow rates there.
So tomorrow we're heading home, and I still haven't had a chance to write about everything we've done. Once I'm back in Boston -- or maybe if I'm sitting around at the airport in Miami tomorrow during our layover -- I'll write another entry to fill in the gaps.